Pressure-based structural cardiac assessment system and method

Abstract

To provide a heart valve evaluation system.SOLUTION: The heart valve evaluation system described herein advantageously provides an instruction of a heart valve state such as a pressure gradient or an index of a valve backflow. The heart valve evaluation system can provide the instruction of the heart valve state during heart treatment. The pressure gradient instructs severity or measurement of valve narrowing (or stenosis) due to an increase in pressure behind the valve. The index of the valve backflow instructs valve leakage measurement.SELECTED DRAWING: Figure 14

Description

Technical Field

[0001] [Incorporation by Reference to Priority Applications] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 849,768, entitled "Pressure Sensing Guidewires, Systems and Methods for Structural Heart Procedures," filed May 17, 2019; U.S. Provisional Patent Application No. 62 / 849,806, entitled "Heart Valve Assessment Systems and User Interfaces," filed May 17, 2019; and U.S. Provisional Patent Application No. 62 / 849,798, entitled "Pressure Based Structural Heart Assessment Systems and Methods," filed May 17, 2019, each of which is hereby incorporated by reference in its entirety.

[0002] This application is directed to devices, user interfaces, algorithms, and systems associated with a structural heart guidewire configured to sense blood pressure to provide information about blood flow through a heart valve before, during, and / or immediately after a structural heart procedure.

Background Art

[0003] Guidewires are known for delivering catheters to many vascular sites in the body. Access to the vascular site is facilitated by a combination of mechanical properties such as flexibility, pushability, and torqueability. It is known that coronary procedures include pressure sensors to enable measurement of blood flow through static occlusions to assist a cardiologist in determining whether to treat a patient.

[0004] While pressure sensing around static lesions in the coronary arteries is known, this concept has not been applied to structural cardiac procedures, such as treating heart valves and improving the heart's pumping function. Pumping function has been addressed with various types of mechanical pumps. Historically, heart valves have been treated by open cardiac surgery. However, nowadays, heart valves are increasingly being replaced by percutaneous cardiac valve implantation, using catheters into which such valves are delivered, performed by cardiologists. [Overview of the project] [Means for solving the problem]

[0005] For the purpose of outlining the present disclosure, certain aspects, advantages, and novel features are discussed herein. Not all such aspects, advantages, and features are necessarily embodied in any specific embodiment of the present invention, and it will be understood that those skilled in the art will recognize countless combinations of such aspects, advantages, or features from the present disclosure herein.

[0006] According to the embodiment, a method for determining the heart valve state during the deployment of a replacement heart valve is disclosed, comprising the steps of: calibrating the second pressure sensor relative to the first pressure sensor while both the first and second pressure sensors are located in the heart; determining a first set of pressure values ​​from the first pressure sensor located in a first part of the heart; determining a second set of pressure values ​​from the second pressure sensor located in a cardiovascular region adjacent to the first part of the heart; adjusting the second set of pressure values ​​at least in part based on the calibration; detecting a first feature in the first set of pressure values; detecting a second feature in the adjusted set of pressure values; determining the heart valve state at least in part based on the first and second features; and displaying the heart valve state on a user interface.

[0007] In one embodiment, the step of calibrating a second pressure sensor with respect to a first pressure sensor may further include: receiving a first calibration pressure value corresponding to a first calibration signal received from a first pressure sensor measuring a first cardiovascular region; receiving a second calibration pressure value corresponding to a second calibration signal received from a second pressure sensor measuring a first cardiovascular region; and calculating calibration parameters based at least in part on the first calibration pressure value and the second calibration pressure value, wherein the step of adjusting a second plurality of pressure values ​​further includes applying the calibration parameters to the second plurality of pressure values.

[0008] In another embodiment, the step of receiving a first calibration pressure value may further include the step of receiving a first plurality of calibration pressure values, the first plurality of calibration pressure values ​​may include a first calibration pressure value, and the first plurality of calibration pressure values ​​may correspond to a first vector; the step of receiving a second calibration pressure value may further include the step of receiving a second plurality of calibration pressure values, the second plurality of calibration pressure values ​​may include a second calibration pressure value, and the second plurality of calibration pressure values ​​may correspond to a second vector; and the step of calculating calibration parameters may further include the step of determining a linear fit between the first vector and the second vector.

[0009] In another embodiment, the first vector can correspond to [P1], the second vector can correspond to [P2], the calibration parameters can include K and b, and the step of determining the linear fit includes determining the relation substantially as [P1] = K·[P2] + b.

[0010] In another embodiment, the first feature may include at least one of a first systolic phase or a first diastolic phase at a first plurality of pressure values.

[0011] In another embodiment, the step of detecting at least one of a first systole or a first diastole may further include the step of detecting a first dicrotic notch feature at a first plurality of pressure values, and the step of identifying at least one of a first systole or a first diastole in accordance with the first dicrotic notch feature.

[0012] In another embodiment, the step of detecting a first dichroic notch feature is to obtain from a first plurality of pressure values Second derivative The steps to calculate and multiple Second derivative A step of identifying zero-intersection points based at least partially on a first dichroic notch feature, the step of which zero-intersection points correspond to a first dichroic notch feature may further include.

[0013] In another embodiment, the step of detecting a first dichroic notch feature may further include: calculating a first angle for a first point from a first plurality of pressure values, at least partially based on a first preceding point and a first succeeding point; calculating a second angle for a second point from a first plurality of pressure values, at least partially based on a second preceding point and a second succeeding point; determining that the second angle is smaller than the first angle; and identifying the second point as the first dichroic notch feature.

[0014] In another embodiment, the second feature may include at least one of a second systole or a second diastolic phase at a plurality of adjusted pressure values.

[0015] In another embodiment, the heart valve state may include an index of regurgitation, and the step of determining the heart valve state may further include the step of calculating the index of regurgitation at least in part on a first subset of a first set of pressure values ​​corresponding to at least one of a first systole or a first diastole, and a second subset of adjusted pressure values ​​corresponding to at least one of a second systole or a second diastole.

[0016] In another embodiment, the heart valve state may include a gradient value, and the step of determining the heart valve state may further include the step of calculating the gradient value on at least in part the difference between a first subset of first pressure values ​​during a first systole and a second subset of adjusted pressure values ​​during a second systole.

[0017] In another embodiment, the step of detecting at least one of a first systole or a first diastole may further include: identifying a first subset of rising pressure values ​​from a first plurality of pressure values; identifying a locally minimum pressure value from the first plurality of pressure values; determining a tangent from the first subset; identifying a horizontal line intersecting the locally minimum pressure value; identifying a first intersection between the tangent and the horizontal line; and identifying a first point from the first plurality of pressure values ​​as the end of a first diastole or the beginning of a first systole, at least in part on the first intersection.

[0018] In another embodiment, the step of identifying the first point may further include the step of adjusting the first intersection by a predetermined time period.

[0019] In another embodiment, the predetermined time period may include approximately 60 milliseconds.

[0020] In another embodiment, the predetermined time period may include a range of approximately 40 milliseconds to approximately 100 milliseconds.

[0021] In another embodiment, the step of identifying the first point may further include the step of adjusting the first crossover in percentages of the heart rate cycle.

[0022] In another embodiment, the percentage may include approximately 8 to 12 percent of the heart cycle.

[0023] In another embodiment, the percentage may include approximately 5 to 8 percent of the heart cycle.

[0024] In yet another aspect, the step of calibrating the second pressure sensor relative to the first pressure sensor can be performed while (i) the first pressure sensor is positioned at a first portion of the heart and (ii) the second pressure sensor is positioned in a cardiovascular region adjacent to the first portion of the heart.

[0025] In yet another aspect, the step of calibrating the second pressure sensor relative to the first pressure sensor includes determining a third plurality of pressure values from the first pressure sensor positioned at a first portion of the heart, determining a fourth plurality of pressure values from the second pressure sensor in a cardiovascular region adjacent to the first portion of the heart, detecting a value at a substantial start of systole among the third plurality of pressure values, and calculating a time adjustment to the fourth plurality of pressure values such that a value from the fourth plurality of pressure values corresponds to the value at the substantial start of systole among the third plurality of pressure values, the step of adjusting the second plurality of pressure values further including applying the time adjustment to the second plurality of pressure values.

[0026] In yet another aspect, the step of calibrating the second pressure sensor relative to the first pressure sensor includes detecting a dicrotic notch feature among the third plurality of pressure values, identifying a time stamp corresponding to the dicrotic notch feature, determining a first value at the time stamp from the third plurality of pressure values, determining a second value at the time stamp from the fourth plurality of pressure values, and calculating a gain adjustment based at least in part on the first value and the second value, the step of adjusting the second plurality of pressure values further including applying the gain adjustment to the second plurality of pressure values.

[0027] According to yet another aspect, the step of calibrating the second pressure sensor relative to the first pressure sensor includes determining a third plurality of pressure values from the first pressure sensor positioned in the first portion of the heart, determining a fourth plurality of pressure values from the second pressure sensor in a cardiovascular region adjacent to the first portion of the heart, detecting a value at a substantial start of systole among the third plurality of pressure values, calculating a time adjustment to the fourth plurality of pressure values such that a value from the fourth plurality of pressure values corresponds to the value at the substantial start of systole among the third plurality of pressure values, detecting a dicrotic notch feature among the third plurality of pressure values, identifying a time stamp corresponding to the dicrotic notch feature, determining a first value at the time stamp from the third plurality of pressure values, determining a second value at the time stamp from the fourth plurality of pressure values and the time adjustment, and calculating a gain adjustment based at least in part on the first value and the second value, the step of adjusting the second plurality of pressure values further including applying the time adjustment and the gain adjustment to the second plurality of pressure values.

[0028] According to yet another aspect, the step of calibrating the second pressure sensor relative to the first pressure sensor may further include identifying a substantial start of systole within a percentage range of the cardiac cycle before or after the end of diastole among the third plurality of pressure values. According to yet another aspect, the percentage may include between approximately 0 percent and 1 percent of the cardiac cycle. According to yet another aspect, the percentage may include between approximately 0 percent and 2 percent of the cardiac cycle. According to yet another aspect, the percentage may include between approximately 0 percent and 5 percent of the cardiac cycle. According to yet another aspect, the percentage may include between approximately 0 percent and 10 percent of the cardiac cycle.

[0029] In another embodiment, the step of identifying a timestamp corresponding to a dichroic notch feature may further include the step of identifying a timestamp within a range of percentages of the heart cycle before or after the dichroic notch in a third plurality of pressure values. In another embodiment, the percentage may include approximately 0 percent to 1 percent of the heart cycle. In another embodiment, the percentage may include approximately 0 percent to 2 percent of the heart cycle. In another embodiment, the percentage may include approximately 0 percent to 5 percent of the heart cycle. In another embodiment, the percentage may include approximately 0 percent to 10 percent of the heart cycle.

[0030] In another embodiment, the first value can correspond to V1, the second value can correspond to V2, the gain adjustment can correspond to g, and the step of calculating the gain adjustment substantially determines the relationship.

[0031]

number

[0032] It could also include the following.

[0033] According to the embodiment, a system is disclosed comprising: a non-temporary computer storage medium configured to store at least computer executable instructions; and one or more hardware processing units communicating with the non-temporary computer storage medium, the hardware processing units configured to execute computer executable instructions to determine a first plurality of pressure values ​​from a first pressure sensor located in a first part of the heart; to determine a second plurality of pressure values ​​from a second pressure sensor located in a cardiovascular region adjacent to the first part of the heart; to detect a first feature in the first plurality of pressure values; to detect a second feature in the second plurality of pressure values; to determine a heart valve state based at least in part on the first and second features; and to display the heart valve state on a user interface.

[0034] In one embodiment, one or more hardware processing devices may be further configured to calibrate the second pressure sensor relative to the first pressure sensor while both the first and second pressure sensors are positioned in the heart.

[0035] In another embodiment, calibrating a second pressure sensor with respect to a first pressure sensor may further include receiving a first calibration pressure value corresponding to a first calibration signal received from a first pressure sensor measuring a first cardiovascular region, receiving a second calibration pressure value corresponding to a second calibration signal received from a second pressure sensor measuring a first cardiovascular region, and calculating calibration parameters based at least in part on the first and second calibration pressure values, wherein determining a second set of pressure values ​​may further include applying the calibration parameters to the initial set of pressure values.

[0036] In another embodiment, receiving a first calibration pressure value may further include receiving a first plurality of calibration pressure values, the first plurality of calibration pressure values ​​including a first calibration pressure value, and the first plurality of calibration pressure values ​​corresponding to a first vector; receiving a second calibration pressure value may further include receiving a second plurality of calibration pressure values, the second plurality of calibration pressure values ​​including a second calibration pressure value, and the second plurality of calibration pressure values ​​corresponding to a second vector; and attempting to calculate calibration parameters may further include determining a linear fit between the first vector and the second vector.

[0037] In another embodiment, the calibration of the second pressure sensor with respect to the first pressure sensor may be performed while (i) the first pressure sensor is positioned in a first part of the heart, and (ii) the second pressure sensor is positioned in a cardiovascular region adjacent to the first part of the heart.

[0038] In another embodiment, calibrating a second pressure sensor with respect to a first pressure sensor may further include determining a third set of pressure values ​​from a first pressure sensor located in a first part of the heart, determining a fourth set of pressure values ​​from a second pressure sensor in a cardiovascular region adjacent to the first part of the heart, detecting a value at the substantial start of systole in the third set of pressure values, and calculating a time adjustment to the fourth set of pressure values ​​such that the value from the fourth set of pressure values ​​corresponds to the value at the substantial start of systole in the third set of pressure values, wherein determining a second set of pressure values ​​may further include calculating the time adjustment to apply to the initial set of pressure values.

[0039] In another embodiment, calibrating the second pressure sensor with respect to the first pressure sensor may further include detecting dicrotic notch features in a third plurality of pressure values, identifying timestamps corresponding to the dicrotic notch features, determining a first value in the timestamps from the third plurality of pressure values, determining a second value in the timestamps from a fourth plurality of pressure values, and calculating a gain adjustment based at least in part on the first and second values, wherein determining the second plurality of pressure values ​​further includes applying the gain adjustment to the initial plurality of pressure values.

[0040] In another embodiment, calibrating the second pressure sensor with respect to the first pressure sensor involves determining a third set of pressure values ​​from the first pressure sensor located in a first part of the heart, determining a fourth set of pressure values ​​from the second pressure sensor in a cardiovascular region adjacent to the first part of the heart, detecting the value at the effective start of systole in the third set of pressure values, calculating a time adjustment to the fourth set of pressure values ​​so that the value from the fourth set of pressure values ​​corresponds to the value at the effective start of systole in the third set of pressure values, and the third set of The calculation involves detecting a dicrotic notch feature in the pressure value, identifying a timestamp corresponding to the dicrotic notch feature, determining a first value in the timestamp from a third set of pressure values, determining a second value in the timestamp from a fourth set of pressure values ​​and time adjustments, and calculating gain adjustments based at least partially on the first and second values, wherein determining the second set of pressure values ​​further includes applying the time adjustments and gain adjustments to the initial set of pressure values.

[0041] In another embodiment, calibrating the second pressure sensor with respect to the first pressure sensor may further include identifying the substantial start of systole within a range of percentages of the heart cycle before or after the end of diastole at a third set of pressure values. In another embodiment, the percentage may range from approximately 0 percent to 1 percent of the heart cycle. In yet another embodiment, the percentage may range from approximately 0 percent to 2 percent of the heart cycle. In yet another embodiment, the percentage may range from approximately 0 percent to 5 percent of the heart cycle. In yet another embodiment, the percentage may range from approximately 0 percent to 10 percent of the heart cycle.

[0042] In another embodiment, identifying a timestamp corresponding to a dichroic notch feature may further include identifying a timestamp within a percentage range of the heart cycle before or after the dichroic notch in a third set of pressure values. In another embodiment, the percentage may range from approximately 0 percent to 1 percent of the heart cycle. In yet another embodiment, the percentage may range from approximately 0 percent to 2 percent of the heart cycle. In yet another embodiment, the percentage may range from approximately 0 percent to 5 percent of the heart cycle. In yet another embodiment, the percentage may range from approximately 0 percent to 10 percent of the heart cycle.

[0043] In another embodiment, the first value can correspond to V1, the second value can correspond to V2, the gain adjustment can include g, and calculating the gain adjustment substantially determines the relationship.

[0044]

number

[0045] It could also include this.

[0046] In another embodiment, the first feature may include at least one of a first systolic phase or a first diastolic phase at a first plurality of pressure values.

[0047] In another embodiment, detecting at least one of a first systole or a first diastole may further include detecting a first dicrotic notch feature at a first plurality of pressure values ​​and identifying at least one of a first systole or a first diastole in accordance with the first dicrotic notch feature.

[0048] In another embodiment, detecting a first dicrotic notch feature involves selecting multiple pressure values ​​from a first set of pressure values. Second derivative Calculating and multiple Second derivativeIdentifying zero-intersection points based at least partially on the above, which may further include identifying zero-intersection points that correspond to a first dichroic notch feature.

[0049] In another embodiment, detecting a first dichroic notch feature may further include: calculating a first angle for a first point from a first set of pressure values, at least partially based on a first preceding point and a first succeeding point; calculating a second angle for a second point from a first set of pressure values, at least partially based on a second preceding point and a second succeeding point; determining that the second angle is smaller than the first angle; and identifying the second point as the first dichroic notch feature.

[0050] In another embodiment, the second feature may include at least one of a second systole or a second diastolic phase at a plurality of adjusted pressure values.

[0051] In another embodiment, the heart valve state may include an index of regurgitation, and determining the heart valve state may further include calculating the index of regurgitation at least in part on a first subset of a first set of pressure values ​​corresponding to at least one of a first systole or a first diastole, and a second subset of adjusted pressure values ​​corresponding to at least one of a second systole or a second diastole.

[0052] In another embodiment, the heart valve state may include a gradient value, and determining the heart valve state may further include calculating the gradient value on at least in part the difference between a first subset of first pressure values ​​during a first systole and a second subset of adjusted pressure values ​​during a second systole.

[0053] In another embodiment, detecting at least one of a first systole or a first diastole may further include identifying a first subset of rising pressure values ​​from a first plurality of pressure values; identifying a locally minimum pressure value from the first plurality of pressure values; determining a tangent from the first subset; identifying a horizontal line intersecting the locally minimum pressure value; identifying a first intersection between the tangent and the horizontal line; and identifying a first point from the first plurality of pressure values ​​as the end of a first diastole or the beginning of a first systole, at least in part on the first intersection.

[0054] In another embodiment, specifying the first point may further include adjusting the first intersection by a predetermined time period. In another embodiment, the predetermined time period may include approximately 60 milliseconds. In yet another embodiment, the predetermined time period may include a range of approximately 40 milliseconds to approximately 100 milliseconds.

[0055] In another embodiment, specifying the first point may further include adjusting the first crossover in terms of a percentage of the heart rate cycle. In yet another embodiment, the percentage may range from approximately 8 percent to 12 percent of the heart rate cycle. In yet another embodiment, the percentage may range from approximately 5 percent to 8 percent of the heart rate cycle.

[0056] In another embodiment, a system is disclosed comprising: a pressure guide wire configured to be positioned in a first cardiovascular region; a second pressure sensing device configured to be positioned in a second cardiovascular region adjacent to the first cardiovascular region; and one or more hardware processing devices configured to determine a first set of pressure values ​​from the pressure guide wire, to determine a second set of pressure values ​​from the second pressure sensing device, to detect a first feature in the first set of pressure values, to detect a second feature in the second set of pressure values, to determine a heart valve state based at least partially on the first and second features, and to display the heart valve state on a user interface.

[0057] In one embodiment, one or more hardware processing devices are further configured to calibrate one of the pressure guide wire or the second pressure sensing device relative to the other while both are positioned in the same cardiovascular region.

[0058] In another embodiment, calibrating either a pressure guide wire or a second pressure sensing device may further include receiving a first calibration pressure value corresponding to a first calibration signal received from a pressure guide wire measuring a first cardiovascular region, receiving a second calibration pressure value corresponding to a second calibration signal received from a second pressure sensing device measuring a first cardiovascular region, and calculating calibration parameters based at least in part on the first and second calibration pressure values, and determining a second plurality of pressure values ​​may further include applying the calibration parameters to the second plurality of pressure values.

[0059] In another embodiment, receiving a first calibration pressure value may further include receiving a first plurality of calibration pressure values, the first plurality of calibration pressure values ​​including a first calibration pressure value, and the first plurality of calibration pressure values ​​corresponding to a first vector; receiving a second calibration pressure value may further include receiving a second plurality of calibration pressure values, the second plurality of calibration pressure values ​​including a second calibration pressure value, and the second plurality of calibration pressure values ​​corresponding to a second vector; and attempting to calculate calibration parameters may further include determining a linear fit between the first vector and the second vector.

[0060] In another embodiment, a method for determining the heart valve state during the deployment of a replacement heart valve is disclosed, which includes the steps of: detecting a first feature from a first set of pressure values ​​in response to a measurement by a first pressure sensor located in a first part of the heart; detecting a second feature from a second set of pressure values ​​in response to a measurement by a second sensor located in a cardiovascular region adjacent to the first part of the heart; determining the heart valve state based at least partially on the first and second features; and displaying the heart valve state on a user interface.

[0061] In another embodiment, a method is disclosed for calibrating a pressure waveform used to determine the heart valve state during the deployment of a replacement heart valve, comprising the steps of: receiving a first calibration pressure value corresponding to a first calibration signal received from a first pressure sensor measuring a first cardiovascular region; receiving a second calibration pressure value corresponding to a second calibration signal received from a second pressure sensor measuring the same first cardiovascular region; calculating calibration parameters based at least in part on the first and second calibration pressure values; determining a first set of pressure values ​​from a first pressure sensor located in a first part of the heart; determining a second set of pressure values ​​from a second pressure sensor located in a cardiovascular region adjacent to the first part of the heart; adjusting the second set of pressure values ​​based at least in part on the calculated calibration parameters; and determining the heart valve state using the adjusted second set of pressure values.

[0062] In one embodiment, the step of determining the heart valve state may further include the step of using a first set of pressure values.

[0063] In another embodiment, the cardiac valve condition may include an indicator of the severity of valve stenosis.

[0064] In another embodiment, the cardiac valve condition may include an indicator of corrected aortic regurgitation.

[0065] According to the embodiment, the steps include: receiving a first plurality of pressure values, each of which pressure values ​​from the first plurality of pressure values ​​corresponds to a first signal received from a first pressure sensor measuring a first part of the heart; receiving a second plurality of pressure values, each of which pressure values ​​from the second plurality of pressure values ​​corresponds to a second signal received from a second pressure sensor measuring a cardiovascular region adjacent to the first part of the heart; and presenting a first user interface for a first gradient type, the first user interface visually presenting a first graph based at least partially on the first plurality of pressure values, a second graph based at least partially on a second plurality of pressure values, and a second graph that visually presents the region between the first graph and the second graph. A method is disclosed for presenting an interactive graphical user interface for a patient monitoring device during the deployment of a replacement heart valve, comprising the steps of: providing a first gradient drawing, the region of which indicates the pressure difference between a first part of the heart and a second part of the heart and a first gradient of the valve; receiving a user selection for a second gradient type via a first user interface; and presenting a second user interface for the second gradient type instead of the first user interface, the second user interface comprising a first graph and a second graph, and a second gradient drawing that visually presents a gradient measurement between a first peak in the first graph and a second peak in the second graph.

[0066] In one embodiment, the first user interface may further include a numerical value indicating the amount of backflow through the valve.

[0067] In another embodiment, the first user interface may further include a backflow depiction that visually presents a backflow measurement between a first point in a first graph and a second point in a second graph, wherein the backflow measurement indicates quantitative backflow of the valve.

[0068] In another embodiment, the first user interface may further include a numerical value for the first gradient of the valve in accordance with statistical measurements.

[0069] In another embodiment, the method may further include the steps of receiving a second user selection for a third gradient type via a second user interface, and presenting a third user interface for the third gradient type in place of the second user interface, wherein the third user interface includes a first graph and a second graph, as well as a third gradient drawing that visually presents a second gradient measurement between a first point in the first graph and a second point in the second graph.

[0070] In another embodiment, the first user interface may further include a first numerical value for a first gradient and a second numerical value for a second gradient.

[0071] In another embodiment, the first numerical value and the second numerical value are presented on a display device that includes a first graph and a second graph.

[0072] In another embodiment, the method may further include the step of presenting a third user interface, including an electrocardiogram recording graph.

[0073] In another embodiment, the method may further include the steps of detecting high-frequency pacing from at least one of a first set of pressure values ​​or a second set of pressure values, and presenting a warning of high-frequency pacing to the user interface.

[0074] In another embodiment, the first user interface may further include a first numerical value for a first gradient, and the method may further include the steps of receiving a user heart rate selection and calculating a first numerical value based at least in part on the user heart rate selection.

[0075] In another embodiment, user heart rate selection may further include the number of heart rates, and the step of calculating the first value may further include the step of determining the first value in accordance with a statistical measurement of the number of heart rates.

[0076] In another embodiment, user heart rate selection may include the selection of a specific heart rate.

[0077] In another embodiment, the step of calculating the first value may further include the step of determining the first value for a specific heart rate.

[0078] In another embodiment, the step of calculating the first value may further include the step of determining the first value for one or more other heartbeats excluding a specific heartbeat.

[0079] In another embodiment, a system is disclosed comprising: a non-temporary computer storage medium configured to store at least computer executable instructions; and one or more hardware processing units communicating with the non-temporary computer storage medium, which are configured to execute computer executable instructions, to present a first user interface for a first gradient type, the first user interface including a first graph based at least in part on the first plurality of pressure values, a second graph based at least in part on a second plurality of pressure values, and a first gradient drawing that visually presents a first gradient measurement between a first peak in the first graph and a second peak in the second graph.

[0080] In one embodiment, one or more hardware processing devices are configured to present a second user interface for a second gradient type in place of a first user interface, so as to receive a user selection for a second gradient type via a first user interface, the second user interface may be further configured to present a first graph and a second graph, as well as a second gradient depiction that visually presents a region between the first graph and the second graph, the region including a second gradient depiction that indicates the pressure difference between a first part of the heart and a second part of the heart and a second gradient of a valve.

[0081] In another embodiment, one or more hardware processing devices may be configured to present a second user interface for a second gradient type in place of the first user interface, so as to receive a user selection for a second gradient type via the first user interface, the second user interface may be further configured to present a first graph and a second graph, as well as a second gradient drawing that visually presents a second gradient measurement between a first point in the first graph and a second point in the second graph.

[0082] In another embodiment, the first user interface may further include a numerical value indicating the amount of backflow from the valve.

[0083] In another embodiment, the first user interface may further include a backflow depiction that visually presents a backflow measurement between a first point in a first graph and a second point in a second graph, wherein the backflow measurement indicates quantitative backflow of the valve.

[0084] In another embodiment, the first user interface may further include a numerical value for the first gradient of the valve in accordance with statistical measurements.

[0085] In another embodiment, the first user interface may further include a first numerical value for a first gradient and a second numerical value for a second gradient.

[0086] In another embodiment, the first numerical value and the second numerical value may be displayed on a display device that includes a first graph and a second graph.

[0087] In another embodiment, one or more hardware processing devices may be further configured to present a third user interface including an electrocardiogram recording graph.

[0088] In another embodiment, one or more hardware processing devices may be further configured to detect high-frequency pacing from at least one of a first plurality of pressure values ​​or a second plurality of pressure values, and to present a warning of high-frequency pacing to the user interface.

[0089] In another embodiment, the first user interface may further include a first numerical value for a first gradient, and one or more hardware processing devices may be further configured to receive a user heart rate selection and to calculate a first numerical value based at least in part on the user heart rate selection.

[0090] In other embodiments, a system is disclosed comprising: a pressure guide wire configured to be positioned in a first cardiovascular region; a second pressure sensing device configured to be positioned in a second cardiovascular region adjacent to the first cardiovascular region; and one or more hardware processing devices configured to present a first user interface for a first gradient type, wherein the first user interface includes a first graph based at least partially on the first plurality of pressure values, a second graph based at least partially on the second plurality of pressure values, and a first numerical value for the first gradient of the valve.

[0091] In one embodiment, the first user interface may further include a first gradient depiction that visually presents a first gradient measurement between a first point in a first graph and a second point in a second graph.

[0092] In another embodiment, one or more hardware processing devices are configured to present a second user interface for a second gradient type in place of a first user interface, so as to receive a user selection for a second gradient type via a first user interface, the second user interface may be further configured to present a first graph and a second graph, as well as a second gradient depiction that visually presents a region between the first graph and the second graph, the region including a second gradient depiction indicating a pressure difference between a first part of the heart and a second part of the heart and a second gradient of a valve.

[0093] In another embodiment, one or more hardware processing devices may be configured to present a second user interface for a second gradient type instead of the first user interface, so as to receive a user selection for a second gradient type via the first user interface, the second user interface may be further configured to present a second gradient drawing which visually presents a first graph and a second graph, as well as a second gradient measurement between a first peak in the first graph and a second peak in the second graph.

[0094] In another embodiment, the first user interface may further include a second numerical value indicating the amount of valve backflow.

[0095] In another embodiment, the first user interface may further include a backflow depiction that visually presents a backflow measurement between a first point in a first graph and a second point in a second graph, wherein the backflow measurement indicates quantitative backflow of the valve.

[0096] In another embodiment, the first user interface may further include a second numerical value for the first gradient of the valve in accordance with statistical measurements.

[0097] In another embodiment, the first user interface may further include a second numerical value for the second gradient.

[0098] In another embodiment, the first numerical value and the second numerical value are presented on a display device that includes a first graph and a second graph.

[0099] In another embodiment, one or more hardware processing devices may be further configured to present a second user interface including an electrocardiogram recording graph.

[0100] While coronary guide wires for measuring pressure have been described and commercially available for many years, structural cardiac guide wires have not been developed. Therefore, structural cardiac guide wires are needed to enable cardiologists to improve structural cardiac procedures.

[0101] During structural cardiac procedures, downstream and upstream pressure curves can be used to determine the state of the heart valves and the state of blood flow through the valves, and in some cases, to determine when and how to treat the patient. Depending on the valve being treated and the procedure, in some practices, the downstream pressure curve may be provided by a pressure sensor on a guide catheter, a pressure guide wire, or other device capable of sensing pressure. The upstream pressure curve may be provided by a pressure guide wire or other device capable of sensing pressure upstream of the downstream pressure measurement. In other practices, the upstream pressure curve may be provided by a guide catheter pressure sensor, a pressure guide wire, or other device capable of sensing pressure. The downstream pressure curve may be provided by a pressure guide wire or other device capable of sensing pressure downstream of the upstream pressure measurement.

[0102] For example, some methods for evaluating heart valves include a step of accessing the patient's blood flow pathway at an access site. The access site may be the femoral artery, radial artery, femoral vein, radial vein, left ventricular apex, or other location. A pressure guide wire may be advanced through the access site to a location adjacent to the patient's treatment site, such as the heart valve to be evaluated, treated, or replaced. A pressure sensing device separate from the pressure guide wire may be advanced to the opposite side of the treatment site, such as the side of the heart valve opposite to the valve side, where a pressure sensing device positioned toward the distal end of the pressure guide wire may be located. The pressure sensing device may comprise or be positioned on an aortic pigtail catheter, a guide catheter, a pressure guide wire, or other device capable of sensing pressure. A treatment device, such as a balloon or replacement heart valve, may be advanced along the pressure guide wire. In some practices, a pressure sensing device can sense pressure on a first side of a heart valve, such as in the aorta or atrium, and a pressure guide wire can sense pressure on a second side of a heart valve, such as in the left or right ventricle. In some practices, a pressure sensing device can sense pressure in a cardiac chamber, and a pressure guide wire can sense pressure in the blood flow passage opposite a heart valve, such as in a second cardiac chamber or aorta. Specific examples include positioning a pressure sensing device in the left ventricle to sense pressure in the left ventricle, and positioning a pressure guide wire in the aorta to sense pressure in the aorta and evaluate the aortic valve from a transapical approach to the heart. Another specific example includes positioning a pressure sensing device in the left ventricle to sense pressure in the left ventricle, and positioning a pressure guide wire in the left atrium to sense pressure in the left atrium and evaluate the mitral valve from a transapical approach to the heart. Pressure measurement can be used to measure the condition of a valve, such as the pressure gradient before and after heart valve and / or valve regurgitation.

[0103] The methods described herein may include a step of equalizing pressure measurements between a pressure sensing device and a pressure guide wire. Pressure equalization can be performed at any location, such as the aorta or left ventricle. The step of equalizing pressure measurements may include automatically or manually adjusting for a phase lag between the pressure curve generated by the pressure sensing device and the pressure curve generated by the pressure guide wire.

[0104] Some of the methods described herein are directed toward addressing and / or treating cardiac and / or cardiovascular conditions. In some cases, the methods include treating structural cardiac conditions. For example, the methods may include steps of accessing the patient's blood flow pathway at an access site, advancing an access catheter through the access site to a location in the heart, advancing a pressure guide wire through the access catheter, and / or sensing pressure using the pressure guide wire. The methods may also include steps of inducing high-frequency pacing through the pressure guide wire. For example, an electric current may be delivered from a proximal section of the pressure guide wire through the core wire of the pressure guide wire to a distal section of the pressure guide wire. The access catheter or other delivery catheter may isolate the patient from the electric current in the high-frequency pacing pressure guide wire. In some configurations, the pressure guide wire may have an insulator along at least a portion of the pressure guide wire, for example, a polymer layer such as a PTFE layer, which may isolate the patient from the high-frequency pacing pressure guide wire when the application of electric current is not desired. By combining pressure sensing with high-frequency pacing capabilities, these methods eliminate the need for a separate pacing device and / or the need to replace such a device in order to continuously apply these capabilities.

[0105] Various pressure guide wire configurations are suitable for the pressure sensing methods described herein. These pressure guide wires can guide other catheters that are advanced across the pressure guide wire. The distal section of the catheter may include a curve to provide a non-traumatic tip. The pressure guide wire may have a distal tip to surround the distal end of the pressure guide wire, for example, to prevent fluid flow or structural passage through the distal end of the pressure guide wire.

[0106] Some of the pressure guide wires described herein may comprise an outer tube having a lumen extending through it. At least a portion of the outer tube comprises a coiled portion and / or a connector tube. The pressure guide wire may also comprise a core wire extending through at least a portion of the lumen of the outer tube. In some configurations, the core wire may extend for substantially the entire length or the entire length of the lumen of the outer tube. The core wire may comprise a portion with a reduced diameter, such as a tapered portion. The pressure guide wire may also comprise a pressure sensor assembly having a pressure sensor and one or more pressure wire leads extending from the pressure sensor toward the proximal end of the pressure guide wire. For example, the pressure sensor may be an optical sensor, an electrical sensor, a MEMS sensor, or a membrane-based sensor, and the pressure wire leads may be optical fibers or electric wires. The pressure sensor may be positioned radially between the portion with a reduced diameter of the core wire and the coiled portion of the outer tube. The pressure sensor may be housed in a sensor housing, or the outer tube itself may provide the sensor housing. The pressure sensor may be exposed to the blood flow outside the pressure guide wire, or may be in pressure communication with the blood flow outside the pressure guide wire, through the space in the coil portion and / or through one or more openings in the sensor housing.

[0107] At least a portion of at least one pressure wire lead does not have to be concentric with the outer tube. For example, a first region of the pressure wire lead can be concentric with the outer tube, and a second region of the pressure wire lead can be asynchronous with respect to the longitudinal axis of the outer tube. The second region can be located radially outward of the core wire. For example, in the distal region of a pressure guide wire having a reduced diameter, there may be space between the core wire and the outer tube so that the pressure sensor can be positioned asynchronous with respect to the longitudinal axis of the outer tube. When the pressure sensor is positioned in the distal region of the pressure guide wire, the pressure guide wire can measure pressure at a position that is more centrally located in the heart cavity, while the core wire maintains structural integrity in the distal region. However, it may be beneficial for at least a portion of the pressure wire lead to be concentric with the outer tube to facilitate connection to an optical connector or other connector at the proximal end of the pressure guide wire.

[0108] The outer tube may have an opening configured to allow at least one pressure wire lead to move from a first region concentric with the outer tube to a second region not concentric with the outer tube. The opening may be a cut-off portion of the outer tube's thickness or may extend through the entire thickness of the outer tube. If the opening extends through the entire thickness of the outer tube, it may be sealed, for example, with an adhesive, to prevent fluid from flowing through the opening to the pressure guide wire.

[0109] In some practices, to induce high-frequency pacing, current may be delivered through the core wire to a conductive surface on the outside of the guide wire. When the core wire extends substantially or over the entire working length of the pressure guide wire, the current generator can deliver current directly to the core wire or to an exposed conductor in direct or indirect contact with the proximal portion of the core wire. Additionally or alternatively, the current may be delivered to a conductive tube and / or coil and then transmitted directly or indirectly to the core wire, for example, through another conductive connector. In some configurations, the outer tube of the pressure guide wire may have an insulator, such as a polymer layer, such as PTFE, along at least a portion of the pressure guide wire to isolate the patient from the core wire.

[0110] Some of the pressure guide wires described herein comprise a connector tube, a core wire, a coil portion, and / or a pressure sensor assembly. The connector tube may extend from the proximal end of the voltage guide wire so that a current generator can be connected to the connector tube. The core wire may extend distal to the distal end of the connector tube, for example, through the distal end of the connector tube, or distal to the distal end of the connector tube. The core wire may have a reduced diameter portion, such as a tapered portion. In some practices, current may be supplied directly or indirectly from the connector tube to the core wire for high-frequency pacing. For example, when using optical sensing, the current may be supplied from the connector tube to the core wire via a connector separate from the connector for optical coupling.

[0111] The coil portion may be located distal to the distal end of the connector tube and may surround at least a portion of the core wire. The coil portion may include a sensor housing area, such as a tube or weld, that is more rigid than other areas or the rest of the coil portion. The pressure sensor of the pressure sensor assembly may be located within the sensor housing area of ​​the coil portion. In this configuration, the sensor housing area of ​​the coil portion may have one or more openings to allow blood, or other fluids that are in pressure communication with blood, to reach the pressure sensor.

[0112] A pressure sensor assembly may comprise a pressure sensor and one or more pressure wire leads extending from the pressure sensor toward the proximal end of a pressure guide wire. For example, the pressure sensor may be an optical sensor, an electrical sensor, a MEMS sensor, or a membrane-based sensor. The pressure sensor may be positioned radially between a reduced-diameter portion of the core wire and the coil portion so that fluid can flow to the pressure sensor through the space in the coil portion. In some configurations, the pressure sensor assembly may comprise a separate pressure housing positioned across the pressure sensor.

[0113] The pressure wire lead can be an optical fiber or an electric wire. At least one pressure wire lead may have a first section concentric with the connector tube, and a second section of the pressure wire lead may be asynchronous with respect to the longitudinal axis of the connector tube. The second section of the pressure wire lead may be located radially outward of the core wire. The tube wall of the connector tube may have an opening to allow the pressure wire lead to move from the first section concentric with the connector tube to the second section asynchronous with respect to the longitudinal axis of the connector tube. The opening may be a cut-off portion of the thickness or may extend through the entire thickness of the connector tube. If the opening extends through the entire thickness of the outer tube, the opening may be sealed to prevent fluid from flowing through the opening to the pressure guide wire. In other configurations, the pressure guide wire may have another connector with an opening to allow the pressure wire lead to move from the first section concentric with the connector tube to the second section asynchronous with respect to the longitudinal axis of the connector tube.

[0114] Some of the pressure guide wires discussed herein comprise an outer tube, a connector tube positioned radially inward of the outer tube, a pressure sensor assembly, and / or a distal end at the distal end of the outer tube. The outer tube may have a uniform or substantially uniform diameter. The core wire may be positioned distal to the connector tube. The core wire may have a reduced diameter portion, such as a tapered portion. The pressure sensor assembly may comprise a pressure sensor positioned distal to the connector tube, for example, radially between the coil portion of the outer tube and the core wire. The pressure sensor assembly may also comprise one or more pressure wire leads extending from the pressure sensor through the lumen of the connector tube.

[0115] The pressure guide wire may include, for example, a sensor housing in the outer tube or within the outer tube, extending over the pressure sensor. The sensor housing may have at least one opening to allow blood or other fluids to flow to the pressure sensor. In this configuration, the pressure guide wire may include a second coiled portion extending proximal to the proximal end of the pressure guide wire from the sensor housing. The coiled portion of the outer tube may extend along most of the working length of the pressure guide wire, or substantially along the entire working length of the pressure guide wire. The proximal end of the connector tube may be exposed from the proximal end of the second coiled portion to facilitate high-frequency pacing. For example, less than 10 percent or less than 5 percent of the length of the connector tube may be exposed from the proximal end of the second coiled portion.

[0116] In various embodiments, systems and / or computer systems are disclosed, comprising a computer-readable storage medium in which program instructions are embodied together, and one or more processing units configured to execute the program instructions in order to perform operations including one or more aspects of the embodiments described above and / or below (including one or more aspects of the appended claims).

[0117] In various embodiments, computer-implemented methods are disclosed in which one or more of the embodiments described above and / or below (including one or more aspects of the appended claims) are practiced and / or carried out by one or more processing units that execute program instructions.

[0118] In various embodiments, computer program products comprising a computer-readable storage medium are disclosed, the computer-readable storage medium having program instructions embodied therewith, the program instructions being executable by one or more processing units to cause one or more processing units to perform operations including one or more of the embodiments described above and / or below (including one or more of the embodiments of the appended claims).

[0119] These and other features, aspects, and advantages are described below with reference to drawings intended for illustrative purposes and not to be construed as limiting the scope of the embodiments. Furthermore, various features of different disclosed embodiments may be combined to form additional embodiments, which is part of this disclosure. In the drawings, similar reference numerals consistently mean corresponding features throughout similar embodiments. The following is a brief description of each of the drawings. [Brief explanation of the drawing]

[0120] [Figure 1A] This is a schematic diagram of pressure guide wires deployed in the heart. [Figure 1B] This is a schematic diagram of pressure guide wires deployed in the heart. [Figure 1C] This is a schematic diagram of pressure guide wires deployed in the heart. [Figure 1D] This is a schematic diagram of pressure guide wires deployed in the heart. [Figure 1E] This is a schematic diagram of pressure guide wires deployed in the heart. [Figure 1F] This is a schematic diagram of pressure guide wires deployed in the heart. [Figure 2A] This is a schematic diagram of a system with a console and guide wires adapted to facilitate the delivery of structural cardiac devices. [Figure 2B] Figure 2 is a plan view of the coiled distal end of a pressure-sensing guide wire that can be incorporated into the system. [Figure 2C] This is a lateral cross-sectional view of a system including an aortic pigtail catheter and a guide catheter for a TAVR delivery system. [Figure 2D] This is a lateral cross-sectional view of a system including a guide catheter for a TMVR delivery system. [Figure 3] Figure 2B is a schematic diagram of one of the deformations of the pressure-sensing guide wire shown. [Figure 4] Figure 2B shows another cross-sectional view of the deformation of the pressure-sensing guide wire. [Figure 5] Figure 2B is another schematic diagram of a deformation of the pressure-sensing guide wire shown. [Figure 6] Figure 2B shows another cross-sectional view of the deformation of the pressure-sensing guide wire. [Figure 7] Figure 2B is another schematic diagram of a deformation of the pressure-sensing guide wire shown. [Figure 8] Figure 2B is another schematic diagram of a deformation of the pressure-sensing guide wire shown. [Figure 9] Figure 2B shows another cross-sectional view of the deformation of the pressure-sensing guide wire. [Figure 10A] This is a diagram of the user interface for a heart valve evaluation system. [Figure 10B] This is a diagram of the user interface for a heart valve evaluation system. [Figure 10C] This is a diagram of the user interface for a heart valve evaluation system. [Figure 10D] This is a diagram of the user interface for a heart valve evaluation system. [Figure 10E]This is a diagram of the user interface for a heart valve evaluation system. [Figure 11A] This is a diagram of an additional user interface for a heart valve evaluation system. [Figure 11B] This is a diagram of an additional user interface for a heart valve evaluation system. [Figure 11C] This is a diagram of an additional user interface for a heart valve evaluation system. [Figure 12] This is a diagram of the configuration user interface for a heart valve evaluation system. [Figure 13] This is a flowchart illustrating the user interface generation process. [Figure 14] This is a diagram of a heart valve evaluation system. [Figure 15] This is a flowchart of the heart valve evaluation process. [Figure 16] This is a flowchart of the calibration process. [Figure 17] This is a diagram of the waveform analysis shown in the example. [Figure 18] This is a diagram of waveform analysis for an additional example. [Figure 19] This is a flowchart of the calibration process. [Figure 20] This is a diagram of waveform analysis for an additional example. [Figure 21] This is a diagram of waveform analysis for an additional example. [Figure 22] This is a diagram of waveform analysis for an additional example. [Figure 23] This is a diagram of waveform analysis for an additional example. [Figure 24] This is a diagram of waveform analysis for an additional example. [Figure 25] This is a diagram of waveform analysis for an additional example. [Figure 26] This is a diagram of waveform analysis for an additional example. [Figure 27] This is a flowchart of another calibration process. [Figure 28] This is another diagram of a cardiac valve evaluation system in which various methods and systems discussed herein may be put into practice. [Modes for carrying out the invention]

[0121] This application is directed to a system and method for providing pressure curves during surgical cardiac procedures, including valvuloplasty, transcatheter aortic valve replacement (TAVR), sometimes called transcatheter aortic valve implantation (TAVI), and transcatheter mitral valve replacement (TAMR). The system and method can be used to assist cardiologists when completing critical phases of structural cardiac procedures. Embodiments herein can be used to communicate, for example, graphically, the state of a heart valve by user interface output before, during, and / or immediately after the deployment of a structural cardiac device such as an aortic valve, mitral valve, or other heart valve. Embodiments herein can be used to communicate the nature of blood flow through a heart valve before, during, and / or immediately after the deployment of a structural cardiac device such as an aortic valve, mitral valve, or other heart valve. The novel display device provides an intuitive and / or immediate perception of the patient's state to simplify the procedure, facilitate the procedure, and increase the success of the procedure. Further consideration of user interface output can be found in Section III of this application.

[0122] Pressure measurements obtained from the systems and methods described herein may be used to calculate indicators of valvular regurgitation, or indicators of heart valves or blood flow, such as pressure gradients before and after a congenital heart valve, a previously placed replacement heart valve, or a currently implanted replacement heart valve. Valvular regurgitation indicators and pressure gradients allow cardiologists to appropriately assess the heart valves. During cardiac contraction, a larger pressure gradient before and after the aortic valve (or lower pressure in the aorta) may indicate greater valve calcification. A smaller regurgitation indicator at the end of cardiac diastole may indicate greater regurgitation. Further consideration of such calculations can be found in Sections III and IV of this application.

[0123] I. The Methodology Figures 1A–1F illustrate various methods of accessing the heart during structural cardiac procedures. Either the pressure guide wire 30 or a pressure sensing device (e.g., pigtail catheter 10 or access catheter 20) can be used to calculate the upstream pressure curve (with respect to flow), and the other pressure guide wire 30 or pressure sensing device can be used to calculate the downstream pressure curve (with respect to flow). Specific methods are described below with respect to specific heart valves and access techniques, but similar systems may be used to evaluate other valves such as the tricuspid valve or pulmonary valve.

[0124] Figure 1A shows a system and method for measuring the performance of an existing or replaced aortic heart valve. The existing heart valve may be a congenitally diseased valve accessed in a subsequent procedure, or a previously implanted replacement heart valve. As illustrated, a pigtail catheter 10 may be positioned downstream of the treatment site, for example downstream of the aortic valve in aortic A, to provide a downstream pressure curve. The pigtail catheter 10 may be used to deliver contrast agent to facilitate visualization of the treatment site. An access catheter 20 may be delivered to the heart from the same or a different access site as the pigtail catheter 10. The access catheter 20, or another delivery catheter replaced by the access catheter 20, may be used to advance a valve inflation balloon, replacement valve, and / or other devices to the treatment site. A pressure guide wire 30 may extend through the access catheter 20 to an upstream location of the treatment site, for example in the left ventricle LV, to provide an upstream pressure curve. The pressure guide wire 30 may be equipped with a pressure sensor 40 at any location along its distal section, such as in the non-traumatic curve, at the transition to the non-traumatic curve, or proximal to the non-traumatic curve (see Figure 2B). Access is provided using arterial techniques, such as femoral or radial techniques, before entering the heart. Figure 1B shows a configuration similar to Figure 1A, except that one or both of the pigtail catheter 10 and / or access catheter 20 may be used to provide pressure readings using an external pressure sensor. The catheter 20 can enable the measurement of downstream pressure as well as pressure read by the pressure guide wire 30. This configuration can be used to equip the pressure guide wire with an external pressure sensor. Alternatively, any other delivery catheter that replaces the access catheter may be used to provide a downstream pressure curve. In some cases, the downstream pressure output may be received by a console that can be coupled with the pressure signals from either or both of the pigtail catheter 10 and access catheter 20.

[0125] It may be important to equalize pressure readings between a downstream and an upstream pressure sensor. Equalization may be performed in terms of pressure accuracy (gain and offset), or in terms of phase lag between the two pressure curves. For example, pressure readings may be taken from the downstream and upstream pressure sensors in the same rough anatomical region, and the pressure measurements may be manually or automatically adjusted for the phase lag between the two pressure curves. As shown in Figure 1B, the pressure measurement for equalization may be taken from the left ventricular LV. In this method, the downstream pressure output is provided by the access catheter 20, and the upstream pressure output is provided by the pressure guide wire 30. The sensing feature of the access catheter 20 (the distal end of the fluid column in the catheter 20) is advanced so as to be adjacent to the sensing feature of the pressure guide wire 30. The sensing feature of the access catheter 20 and the sensing feature of the pressure guide wire 30 may be ensured to be located at the left ventricular LV. The sensing feature portion of the access catheter 20 and the sensing feature portion of the pressure guide wire 30 can be positioned in the same location in the left ventricular LV.

[0126] Figure 1C shows that the pressure sensor 40 is positioned proximal to the non-traumatic curve of the pressure guide wire 30. For example, the sensing feature of the pigtail catheter 10 (the distal end of the fluid column in the catheter 10) is advanced so as to be adjacent to the sensing feature of the pressure guide wire 30. The sensing feature of the pigtail catheter 10 and the sensing feature of the pressure guide wire 30 can be positioned in the aorta A. In this configuration, pressure equalization can be performed in the aorta A. After pressure equalization, the pressure guide wire 30 may be advanced to the left ventricle LV to provide an upstream pressure curve, while the pigtail catheter 10 remains in the aorta A to provide a downstream pressure curve.

[0127] In Figure 1D, the pigtail catheter 10 may be positioned in the aorta A to provide a downstream pressure curve. In this embodiment, a pressure guide wire 30 extends through the pigtail catheter 10 to provide an upstream pressure curve. In this configuration, pressure equalization may be performed in the aorta A. For example, the sensing feature of the pressure guide wire 30 can be advanced to the end of the fluid column in the pigtail catheter 10, or just distal to that end. The signal from the sensing feature of the pressure guide wire 30 and the fluid column can be compared to equalize them (further discussed later in Section IV). After pressure equalization, the pressure guide wire 30 may be retrieved from the pigtail in the aorta and inserted into the left ventricle via an access catheter, as is normally done, but the pigtail catheter 10 remains in the aorta A to provide a downstream pressure curve.

[0128] The systems described herein may be used to measure the performance of an existing or replacement mitral valve. For example, as shown in Figure 1E, the access catheter 20 may be advanced to the right atrium RA via the venous vascular system, for example, from a femoral approach, or via the inferior or superior vena cava VC. The access catheter 20 may then be advanced through the atrial septum to a position in the left atrium LA. In some variations, the access catheter 20 may be configured to provide access through the patient's foramen ovale, or to track a guide wire or device that provided such access. The access catheter 20, or another delivery catheter replaced by the access catheter 20, may be used to advance a valve inflation balloon, replacement valve, and / or other device to the treatment site. A pressure guide wire 30 may extend through the access catheter 20 to the left ventricle LV. The access catheter 20 can provide a pressure signal that can be used to generate an upstream pressure curve, while the pressure guide wire 30 can provide a pressure signal that can be used to generate a downstream pressure curve. Alternatively, any other delivery catheter that replaces the access catheter may be used to provide an upstream pressure curve.

[0129] A similar system may be used in apical techniques for aortic or mitral valve procedures. For example, as shown in Figure 1F, the access catheter 20 can access the left ventricular LV through the apex P of the heart. Another device (not shown) can be used to open a pathway through the apex P. The access catheter 20 may be advanced through a device, etc. The access catheter 20, or another delivery catheter replaced with the access catheter 20, may be used to advance a valve inflation balloon, replacement valve, and / or other device to the treatment site. A pressure guide wire 30 may extend through the access catheter 20 into the aorta A in aortic valve procedures. The access catheter 20 can provide a pressure signal that can be used to calculate an upstream pressure curve, while the pressure guide wire 30 can provide a signal that can be used to calculate a downstream pressure curve. Alternatively, any other delivery catheter replaced with the access catheter may be used to provide an upstream pressure curve.

[0130] Figure 1F shows the evaluation or treatment of the aortic valve via the cusp P of the heart, but the pressure guide wire 30 can be advanced through the mitral valve M so that its sensing feature is in the left atrium. In this method, the pressure guide wire can provide a pressure signal that can be used to calculate the left atrial pressure curve (proximal or upstream pressure curve in terms of flow). The access catheter 20 can generate a pressure signal that can be used to calculate the left ventricular pressure curve (distal or downstream pressure curve in terms of flow).

[0131] During valve inflation procedures, sometimes called valve repair or valve implantation, natural circulation through the heart valves may be obstructed by the valve repair balloon, valve replacement delivery system, or other treatment device. However, when the heart is pumping, pressure from the left ventricular LV or myocardial compression may drive the treatment device back to the aorta A, making it difficult to properly position the device. High-frequency pacing, or defibrillation of the left ventricular LV, can also reduce the pressure gradient between the aorta A and the left ventricular LV, reducing myocardial force and allowing the clinician to complete the procedure. Conventional high-frequency pacing may involve introducing a temporary pacemaker into the heart, which usually requires another access site, such as a venous access site. Temporary pacemakers can burn the heart and cause other complications. Instead, a pressure guide wire 30 may be used to perform high-frequency pacing. As previously described, the pressure guide wire 30 can be introduced through the same access site as the access catheter 20 or other delivery catheter, which reduces the overall number of access sites. The current can be delivered to the pressure guide wire in the proximal section, as will be described in more detail later, and then transmitted to the distal section of the pressure guide wire via the connector tube and / or core wire. The access catheter 20 or other delivery catheter can isolate at least the intermediate section of the high-frequency pacing pressure guide wire 30 from the patient to prevent burns. Alternatively or additionally, the pressure guide wire 30 may have an insulating section to isolate the pressure guide wire 30. As shown in Figure 2B, the distal section of the pressure guide wire may have a curved section that brings the current into contact with multiple locations in the ventricular wall.

[0132] II. Overview and Use of Pressure Wire Systems Figure 2A shows a diagnostic system 200 that may be used in a patient's vascular system. The diagnostic system 200 is configured to determine whether the degree of valve damage is severe enough to indicate that balloon inflation (e.g., valve repair), valve replacement, or other catheter intervention should be performed.

[0133] The diagnostic system 200 may include a monitoring assembly 204 configured to connect to a pressure guide wire 208. The diagnostic system 200 may include a coupling section (indicated by dotted line A) that facilitates the connection of the monitoring assembly 204 to the pressure guide wire 208 and the disconnection of the pressure guide wire 208 from the monitoring assembly 204. Connection to and disconnection from the monitoring assembly 204 is useful when a clinician is initially using the pressure guide wire 208 to assess the effect of cardiac valve injury. The pressure guide wire 208 may be used to deliver therapeutic devices such as balloon catheters or valve delivery systems.

[0134] A fiber optic interface cable 202 may be used to connect a pressure guide wire 208 to a monitoring assembly 204 using a handle 207. In some embodiments, the system 200 receives input from a tubular catheter body used to access the vascular system. For example, the access catheter 20 may be an access catheter. The distal end of the pressure sensor of the access catheter 20, or the distal end of the pressure sensor in the access catheter 20, may be positioned adjacent to the treatment site so that a pressure signal corresponding to the pressure on a first side of the treatment site, such as in the aorta, is obtained. This pressure measurement may be referred to herein as Pa. In other configurations, the system 200 may include a pressure sensor, such as a pigtail catheter, delivered separately from the pressure guide wire, to obtain Pa.

[0135] The pressure guide wire 208 can take any suitable form. For example, the pressure guide wire 208 may include a proximal section having a proximal end positioned outside the patient and a distal end that can be advanced into the vascular system through the access catheter 20. The pressure guide wire 208 may be configured to be flexible to pass through the winding vascular system while maintaining structural integrity for pushability and torqueability. For example, at least the proximal section of the pressure guide wire 208 may be supported by a connector tube and / or core for structural integrity, while the distal section of the pressure guide wire 208 may be formed to have a non-traumatic curved section 250, such as a coiled end shown in Figure 2B, to provide greater flexibility and prevent puncture. In other configurations, the curved distal section may be coupled to the pressure guide wire 208 to provide the non-traumatic curved section 250.

[0136] Any sensing mode can be used. For example, an optical sensor may be configured to sense pressure when exposed to blood. The optical sensor may be located in the internal space of the pressure guide wire 208, which is in fluid communication with the outside of the pressure guide wire 208. The sensor may be an optical or electrical pressure sensor. The sensor may be selectively positioned by communicating with the monitoring assembly 204 via a pressure wire lead located between the sensor and the proximal end of the pressure guide wire 208. The pressure wire lead may be an optical fiber or an electric wire.

[0137] As shown in Figure 2B, the pressure sensor may be positioned at any of the following locations along the distal portion of the pressure guide wire 208. For example, the pressure sensor may be positioned near the most distal end of the guide wire at location 206D, along the curved portion 250 of the guide wire at location 206C, at the transition to the curved portion 250 of the guide wire at location 206B, or proximal to the curved portion 250 of the guide wire at location 206A. For example, location 206C may be at approximately 270 degrees from the straight portion of the pressure guide wire (around location 206A) to the curved portion 250, and location 206D may be at approximately 540 degrees from the straight portion of the pressure guide wire to the curved portion. However, the pressure sensor can be positioned at any point in the curved distal region of the pressure guide wire, from the straight region of the pressure guide wire, for example, between approximately 0 degrees and approximately 90 degrees, between approximately 90 degrees and approximately 180 degrees, between approximately 180 degrees and approximately 270 degrees, between approximately 270 degrees and approximately 360 degrees, between approximately 360 degrees and approximately 450 degrees, or between approximately 450 degrees and approximately 540 degrees.

[0138] When the distal segment is rounded, the pressure sensor may be positioned approximately 270 degrees along the curved section 250 from the straight section of the pressure guide wire 208. The location of the pressure sensor within the distal segment of the guide wire can affect the accuracy of pressure measurement. For example, when the pressure sensor is in a more distal location 206C, 206D, it may be positioned more centrally within a ventricle of the heart, such as the left ventricle (LV), and offset from the ventricular wall. Also, in the more distal locations 206C, 206D, the pressure sensor is less likely to be obstructed by an access catheter or other delivery catheter during valve repair or cardiac replacement procedures. In the more proximal locations 206A, 206B, pressure measurement is performed closer to the heart valve, and equivalence can be performed in the aorta A while maintaining the distal tip of the pressure guide wire 208 within the left ventricle (LV). In some procedures, performing equivalence in the aorta A requires less manipulation of the pigtail catheter or other pressure sensing devices. For example, during aortic valve treatment, the pigtail catheter is already positioned in the aorta. The pressure sensor may be proximal to the curve 250, but it is distal enough to perform pressure measurement distal to the heart valve. Access to the left ventricular LV is maintained by leaving the distal end of the pressure guide wire 208 inside the left ventricular LV.

[0139] Figure 2C shows a cross-section of a TAVR system in a patient's descending aorta, with biostructures removed for clarity. The TAVR system may be used in conjunction with a monitoring and display device 204. For example, a pressure guide wire 208 extends through an access catheter 210. The same access catheter 210 may be used to advance a delivery system 212 across the pressure guide wire 208. The delivery system 212 may be used to advance valve replacement or other therapeutic devices. Other configurations are also possible. For example, the catheter for the access catheter 210 may be replaced with a delivery system 212 and subsequently advanced across the pressure guide wire 208. As illustrated, a pressure sensing device used to provide a pressure signal about the pressure of blood in the aorta is an aortic pigtail catheter 214, which is delivered separately from the access catheter 210, although it is possible from the same access position.

[0140] In other configurations, the access catheter 210 or delivery system 212 may be used to obtain a pressure signal about the blood pressure in the aorta, and therefore may be a pressure sensor for aortic pressure. As shown in Figure 2D, for mitral valve replacement, the access catheter 211 may be a pressure sensor. A pressure guide wire 208 extends through the access catheter 211, and the delivery system 213 may be advanced across the pressure guide wire 208. The delivery system 213 may be used to deliver the mitral valve or other replacement or therapeutic device.

[0141] a. Wire-based pressure guide wire Figures 3 and 4 show different pressure guide wires 308 and 408 that can be used in either of the methods described above. The designation used to identify the features of pressure guide wire 308 is incremented by 100 to identify similar features of pressure guide wire 408. This designation rule generally applies to the rest of the figures as well. Any component of pressure guide wires 308 and 408 is interchangeable.

[0142] Generally, the pressure guide wires 308, 408 comprise outer tubes 310, 410 defining the lumen, core wires 316, 416 extending at least partially through the lumen of the outer tubes 310, 410, pressure sensor assemblies 318, 418 positioned within the lumen of the outer tubes 310, 410, and / or distal tip 432. The pressure guide wire 308 may have a distal tip that is the same as or similar to tip 432, or any other tip disclosed herein. The outer diameter of the pressure guide wires 308, 408 may be uniform or substantially uniform along substantially the entire length of the pressure guide wire 308, 408 or the entire working length. For example, the outer diameter of the pressure guide wire 308 may be uniform or substantially uniform along the entire working length, except for the distal tip 432 or the non-traumatic curved portion 250. The pressure guide wires 308, 408 may have an outer diameter of up to 0.035 inches, for example, between 0.018 inches and 0.035 inches. In some configurations, the distal portions of the pressure guide wires 308, 408 may form a non-traumatic curved portion 250, such as the coiled portion shown in Figure 2B. In other configurations, the distal portions of the pressure guide wires 308, 408 may remain straight from at least the pressure sensor of the pressure sensor assembly to the distal end of the pressure guide wire.

[0143] Figure 3 is a schematic diagram of one variation of the pressure-sensing guide wire 308. As shown, at least the distal portion of the outer tube 310 may be coiled. For example, the coiled portion 312 may be a flat ribbon-shaped coil or a round coil. The coiled portion 312 may extend along most of the working length of the pressure guide wire 308, substantially along the entire working length of the pressure guide wire 308, or along the entire working length of the pressure guide wire 308. If the substantial length of the coiled outer tube 310 is coiled, the coiled portion 312 provides enough flexibility and softness to avoid any trauma during use (e.g., perforation and / or incision). The coiled portion 312 also promotes safety in the event of loss of the distal tip. During high-frequency pacing, the coiled portion 312 can also ensure electrical contact with the heart.

[0144] As shown in Figure 3, at least the proximal portion 328 of the core wire 316 can be concentric with the outer tube 310 and can extend through at least a portion of the lumen of the outer tube 310. For example, the core wire 316 can extend along most of the working length of the pressure guide wire 308, substantially along the entire working length of the pressure guide wire 308, or along the entire working length of the pressure guide wire 308. The core wire 316 provides sufficient rigidity to the pressure guide wire 308 for pushability and to prevent entanglement. The core wire 316 also provides sufficient rigidity to support the delivery catheter during valve implementation.

[0145] At least a portion of the core wire 316 may have a reduced-diameter portion 326 to provide space in the lumen of the outer tube 310 for the pressure sensor 322. For example, as shown in Figure 3, the reduced-diameter portion 326 may be tapered toward the distal end of the pressure guide wire 308. The transition between the proximal portion 328 and the reduced-diameter portion 326 of the core wire 316 may be located proximal to at least a portion or all of the non-traumatic curved portion 250 in the distal region of the pressure guide wire 308 to facilitate a flexible transition of the pressure guide wire 308 to the non-traumatic curved portion 250 (shown in Figure 2B). The core wire 316 continues to extend through at least a portion of the non-traumatic curved portion 250. This flexible transition acts as a force absorber to ensure that tangling does not form in the proximal region of the non-traumatic curved portion 250 of the pressure guide wire 308. Entanglement can complicate procedures, such as advancing another catheter across the guide wire 308 or removing the guide wire 308 from the patient without trauma.

[0146] The proximal portion 328 of the core wire 316 may have an outer diameter of up to 0.03 inches, for example, between 0.015 inches and 0.03 inches. The reduced diameter portion 326 of the core wire 316 may have an outer diameter that is less than one-third or one-quarter of the outer diameter of the proximal portion 328 of the core wire 316. For example, the reduced diameter portion 326 of the core wire 316 may have an outer diameter of less than 0.01 inches or less than 0.0075 inches.

[0147] The core wire 316 may include a conductive material such as stainless steel to provide a conductive path for the current applied to the guide wire 308 in connection with high-frequency pacing technology, as previously described. The proximal end of the core wire 316 may be exposed from the proximal end of the outer tube 310 for connection to the monitoring display device 204 and / or to the current generator. Less than 10 percent or less than 5 percent of the length of the core wire 316 may be exposed from the proximal end of the outer tube 310 for connection to a current source for high-frequency pacing.

[0148] The pressure sensor assembly 318 may comprise a pressure sensor 322 and one or more pressure wire leads 320 extending from the pressure sensor 322. The pressure wire leads 320 may extend along the core wire 316. For example, the pressure sensor 322 may be an optical sensor, an electrical sensor, a membrane-based sensor, a MEMS sensor, or other device capable of generating a signal in response to a pressure level or pressure fluctuation. One or more pressure wire leads 320 may be optical fibers or electric wires. As shown in Figure 3, the pressure sensor assembly 318 may also comprise a sensor housing 324 positioned across the pressure sensor 322 and between the outer tube 310 and the core wire 316. The sensor housing 324 may comprise an annular or short tubular member or cylinder on which the membrane is supported. The sensor housing 324 can improve handling during assembly in the coil portion 312.

[0149] The pressure sensor assembly 318 may be positioned radially between the core wire 316 and the outer tube 310, with the pressure sensor 322 located radially between the reduced diameter portion 326 of the core wire 316 and the coiled portion 312 of the outer tube 310. At least a portion of the pressure sensor assembly 318 may be asynchronous with respect to the longitudinal axis L of the pressure guide wire 308. In some configurations, the entire pressure sensor assembly 318 may be asynchronous with respect to the longitudinal axis of the pressure guide wire 308.

[0150] The pressure sensor 322 may be exposed to blood or other fluids through a gap or void 314 in the coil portion 312. In other variations, the outer tube 310 may include a sensor housing area with one or more openings to expose the pressure sensor 322 to blood or other fluids. The sensor housing area may be more rigid than the rest of the coil portion 312. For example, the sensor housing area may be a metal tube dividing the coil portion 312 into two sections. The sensor housing area may be mounted on the distal portion of the first coil section of the coil portion 312 and the proximal portion of the second coil section of the coil portion 312. In another example, the coil portion 312 may comprise two coils welded together to create a reinforced area.

[0151] At least a portion of the pressure guide wire 308 may be covered with a smooth insulator, such as a polymer layer of PTFE. The insulator can hold one or more pressure wire leads 320 in place. When high-frequency pacing is induced through the core wire 316, the insulator can also electrically isolate the core wire 316 from the patient along the length of the insulator. The insulator can replace requiring a separate catheter to electrically isolate the pressure guide wire 308.

[0152] Figure 4 shows another variation of the pressure guide wire 408. The pressure guide wire 408 may include any of the features described with respect to the pressure guide wire 308. In this variation, the distal portion of the outer tube 410 may be formed by a coil portion 412. The proximal portion of the outer tube 410 may be formed by a connector tube 430. The connector tube 430 may contain a conductive material to facilitate high-frequency pacing. For example, the connector tube 430 may be formed of a metallic structure such as a stainless steel tube. The connector tube 430 is not covered with a coating or other insulator to allow high-frequency pacing. In some configurations, current may flow through one or more pressure wire leads 420, either additionally or alternatively. The connector tube 430 may be directly or indirectly connected to the coil portion 412 and / or distal tip 432. For example, the coil portion 412 may be indirectly connected to the connector tube 430 by an insulated portion. The insulated portion can provide a length that is insulated from the patient and is therefore an insulating portion 434 in some embodiments. The insulating portion 434 can isolate the patient from the core wire 416. In some configurations, the insulating portion 434 may comprise a polymer layer such as PTFE.

[0153] At least the portion of the core wire 416 with an unreduced diameter may be concentric with the outer tube 410. The core wire 416 may extend at least through the coil portion 412, but may also extend through the insulating portion 434 of the outer tube 410 and / or at least a portion of the connector tube 430. For example, the proximal end of the core wire 416 may be sealed to the distal end of the connector tube 430 using, for example, adhesive 436, and extend distally from the distal end of the connector tube 430.

[0154] The core wire 416 may include any of the features of the core wire 316. For example, the distal portion of the core wire 416 may include a reduced-diameter portion 426. The proximal end of the coil portion 412 may be distal to the transition between the non-reduced-diameter portion 428 and the reduced-diameter portion 426 of the core wire 416.

[0155] The pressure sensor assembly 418 may be positioned radially between the core wire 416 and the outer tube 410, with the pressure sensor 422 positioned radially between the reduced diameter portion 426 of the core wire 416 and the coil portion 412. At least a portion of the pressure sensor assembly 418 may be asynchronous with respect to the longitudinal axis L of the pressure guide wire 408. For example, a first section 438a of at least one pressure wire lead 420 may be concentric with the outer tube 410, and a second section 438b of the pressure wire lead 420 may be asynchronous with respect to the longitudinal axis of the outer tube 410. The outer tube 410 may have an opening 440 that allows the pressure wire lead 420 to move from the first section 438a, which is concentric with the outer tube 410, to the second section 438b, which is asynchronous with respect to the longitudinal axis of the outer tube 410. The opening 440 may be a cut-out portion of the thickness, or it may extend through the entire thickness of the outer tube 410. If the opening 440 extends through the entire thickness of the outer tube 410, the opening 440 may be sealed, for example, with adhesive 436, to prevent blood or other fluids from flowing through the opening 440 to the pressure guide wire. As shown in Figure 4, the opening 440 is located in the connector tube 430. However, in other configurations, the opening 440 may be located in the insulating portion 434.

[0156] Alternatively, the core wire 416 may be sized with respect to the longitudinal axis of the pressure guide wire 408, or offset with respect to its longitudinal axis, so as to allow the pressure wire lead 420 to transition from a first region 438a, which is concentric with the outer tube 410, to a second region 438b, which is not coaxial with the longitudinal axis of the outer tube 410. The core wire 416 may have a groove on one side configured to accommodate the expansion of the pressure wire lead 420 so that the lead can transition from the first region 438a to the second region 438b.

[0157] The pressure guide wire 408 may have a rounded distal tip 432 to form a non-traumatic tip. For example, the distal tip 432 may have a hemispherical shape. The tip 432 may be tapered or flattened to prevent unwanted foreign matter from entering through the distal end of the pressure guide wire 408.

[0158] In some configurations, the distal tip 432 is another component attached, welded, and / or otherwise joined to the coil portion 412 and / or the core wire 416. The distal tip may be joined to the inner surface of the coil portion 412 and / or to the most distal edge of the coil portion 412. The core wire 416 may be bent up to 180 degrees within the outer tube 410 to straighten the adhesive bond to the distal tip 432. In other configurations, the distal tip 432 may be the enlarged distal end of the core wire 416, which is distal to the reduced-diameter portion 426. The distal end of the core wire 416 may be attached, welded, and / or otherwise joined to the inner surface of the coil portion 412 and / or to the most distal edge. In one method, the distal tip 432 is formed by deforming an enlarged section of the core wire 416 into a hemispherical member. The enlarged section may be melted to form the hemispherical member. The hemispherical member may be joined to the distal portion of the coil portion 412. In any of these configurations, the non-traumatic portion of the distal tip 432 may be formed from the core wire 416, adhesive, and / or welding.

[0159] b. Pressure guide wires based on pipes Figures 5–9 show further variations of pressure guide wires that may be used in any of the methods described above. The pressure guide wires described below may include any of the features of the pressure guide wires 308, 408 described above. Generally, the pressure guide wires shown in Figures 5–9 comprise an outer tube defining a lumen, a connector tube positioned radially inward of the outer tube, a pressure sensor assembly positioned within the lumen of the outer tube, and / or a distal tip. The outer diameter of the pressure guide wire may be uniform or substantially uniform along substantially the entire length of the pressure guide wire or along its entire working length. For example, the outer diameter of the pressure guide wire may be uniform or substantially uniform along its entire working length, except for the distal tip or a worn-out curved portion. The pressure guide wire may include an outer diameter of up to 0.035 inches, for example, between 0.018 inches and 0.035 inches. In some configurations, the distal portion of the pressure guide wire may be formed into a non-traumatic curved portion 250, as shown in Figure 2B. In other configurations, the distal portion of the pressure guide wire may remain straight.

[0160] The connector tube may include an inner diameter less than one-third or one-quarter of the outer diameter of the connector tube. For example, the connector tube may have an outer diameter of up to 0.035 inches, such as between 0.018 inches and 0.035 inches, and an inner diameter of less than 0.01 inches, such as less than 0.007 inches. The connector tube may have a uniform outer diameter (see Figure 5) or a non-uniform diameter (see Figure 6). In a non-uniform configuration, the reduced diameter portion of the connector tube may have an outer diameter of about 0.027 inches or less. The connector tube may extend along most or substantially the entire working length of the pressure guide wire. For example, the connector tube may extend for at least 80 percent, or at least 90 percent, of the working length of the pressure guide wire.

[0161] The connector tube may be constructed from a conductive metal. For example, the connector tube may be a stainless steel tube. The proximal end of the connector tube may be exposed from the proximal end of the outer tube for connection to a monitoring device and / or a current generator. Therefore, at least the proximal end of the connector tube may not be covered.

[0162] The pressure guide wire may have a core wire distal to the connector tube. In venous or apical transverse aortic valve applications, the portion with the core wire may be positioned in the blood flow downstream of the portion with the connector tube. In arterial or apical transverse mitral valve applications, the portion with the core wire may be positioned in the blood flow upstream of the portion with the connector tube. The core wire may have an outer diameter of up to 0.03 inches, for example, between 0.018 inches and 0.03 inches. The reduced diameter portion of the core wire may have an outer diameter that is less than one-third or one-quarter of the outer diameter of the rest of the core wire. For example, the reduced diameter portion of the core wire may have an outer diameter of less than 0.01 inches or less than 0.0075 inches. The core wire may extend only along the distal portion of the pressure guide wire, for example, along less than 20 percent, less than 10 percent, or less than 5 percent of the working length of the pressure guide wire.

[0163] Figure 5 is a schematic diagram of another variation of the pressure-sensing guide wire 508. As shown, at least the distal portion of the outer tube 510 may be coiled. For example, the coiled portion may be a flat ribbon-shaped coil or a round coil. As shown in Figure 5, the coiled portion may comprise two coiled sections 512a, 512b separated from each other by the sensor housing 542. Together, the coiled sections 512a, 512b may extend along most of the working length of the pressure guide wire 508, or substantially along the entire working length of the pressure guide wire 508. For example, together, the coiled sections 512a, 512b may extend for at least 80 percent, or at least 90 percent, of the working length of the pressure guide wire 508. With a substantial length of the outer tube 510 being coiled, the coiled sections 512a, 512b provide sufficient flexibility to pass through a winding vascular system. The distal coil portion 512a also enhances safety in the event of failure along the coiled portion, such as failure of the distal tip. When used for high-frequency pacing, the distal coil portion 512a may also ensure electrical contact with the inner wall of the patient's heart, such as the inner wall of the left ventricle.

[0164] As shown in Figure 5, at least the proximal portion 528 of the core wire 516 can be concentric with the outer tube 510 and may extend through at least a portion of the lumen of the outer tube 510. The diameter of the proximal portion 528 of the core wire 516 may be the same as the outermost diameter of the connector tube 530. At least a portion of the core wire 516 may include a reduced-diameter portion 526, such as a tapered portion that tapers toward the distal end of the pressure guide wire 508. The transition between the proximal portion 528 and the reduced-diameter portion 526 of the core wire 516 may be located proximal to the non-traumatic curved portion 250 in the distal region of the pressure guide wire 508 to facilitate a flexible transition of the pressure guide wire 508 to the non-traumatic curved portion 250. This flexible transition acts as a force absorber to ensure that tangling does not form in the proximal region of the non-traumatic curved portion 250 of the pressure guide wire 508. Entanglement can complicate the procedure, such as advancing another catheter over the guide wire 508 or removing the guide wire 508 from the patient without trauma. The core wire 516 may include a conductive material such as stainless steel to provide high-frequency pacing, as previously described.

[0165] The pressure sensor assembly 518 may comprise a pressure sensor 522 and one or more pressure wire leads 520 extending from the pressure sensor 522. For example, the pressure sensor 522 may be an optical sensor, an electrical sensor, a membrane-based sensor, or other. The pressure wire leads 520 may be optical fibers or electric wires. The pressure wire leads 520 may extend through the lumen of the connector tube 530. The connector tube 530 positions the pressure wire leads 520 along the central longitudinal axis L of the pressure guide wire 508. The pressure wire leads 520 may be fixed to the connector tube 530, and in some cases may be sealed to the connector tube 530, for example, using an adhesive. In some cases, the adhesive provides a seal to prevent fluid from flowing proximal through the connector tube 530. The adhesive may be used at the proximal end of the connector tube 530 to fix the optical fiber 520 concentrically to the connector tube 530.

[0166] As shown in Figure 5, the pressure sensor 522 may be housed within a pressure sensor housing 542 of the outer tube 510. The sensor housing 542 protects the pressure sensor 522 but also provides a connection between the coil portions 512a and 512b. The pressure sensor 522 may be exposed to blood or other fluids through at least one opening 544 in the sensor housing 542. As shown, the sensor housing 542 may be a metal tube connecting the two coil portions 512a and 512b, but in other variations, the sensor housing 542 may be formed by welding several coils together to form a welded portion connecting the coil portions 512a and 512b.

[0167] The sensor housing 542 and the pressure sensor 522 may be positioned proximal to the non-traumatic curved portion 250 shown in Figure 2B, for example, at location 206A. However, as previously described, the pressure sensor may be positioned at any location along the curved portion 250 in the distal portion of the pressure guide wire 508.

[0168] At least a portion of the pressure guide wire 508 may be covered with a smooth insulator, such as a polymer layer of PTFE. When high-frequency pacing is induced through the connector tube 530 and / or core wire 516, the insulator may electrically isolate a portion of the pressure guide wire 508. The insulator can replace requiring a separate catheter body to electrically isolate the pressure guide wire 508.

[0169] Figure 6 is a cross-sectional view of another variation of the pressure-sensing guide wire 608. The pressure-sensing guide wire 608 is similar to the pressure-sensing guide wire 508, except that it differs from the one described later. The disclosure in relation to Figure 6 may be seen as supplementary to the disclosure in Figure 5. The pressure-sensing guide wire 608 includes a distal tip 632. The distal tip 632 is similar to the distal tip 432, except that it differs from the one described later. The distal tip 632 provides non-traumatic interaction with blood vessels, valves, and ventricular walls. The tip 632 can reduce or prevent the intrusion of foreign matter, such as components or fluids, through the distal end of the pressure-sensing guide wire 608. The distal tip 632 may have a hemispherical shape.

[0170] In some configurations, the distal tip 632 is another component attached, welded, and / or otherwise joined to the coil portion 612a and / or the core wire 616. The distal tip 632 may be joined to the inner surface of the coil portion 612a and / or to the most distal edge of the coil portion 612a. The core wire 616 may be bent up to 180 degrees within the outer tube 610 to straighten the adhesive bond to the distal tip 632. In other configurations, the distal tip 632 may be the enlarged distal end of the core wire 616, which is distal to the reduced-diameter portion 626. The distal end of the core wire 616 may be attached, welded, and / or otherwise joined to the inner surface of the coil portion 612a and / or to the most distal edge. In any of these configurations, the non-traumatic portion of the distal tip 632 may be formed from the core wire 616 by melting or reforming the enlarged portion of the core wire 616, etc., to create the desired shape.

[0171] Figure 7 is a schematic diagram of another variation of the pressure-sensing guide wire 708. The pressure-sensing guide wire 708 is similar to the pressure-sensing guide wire 508, except that the sensor housing 742 and the pressure sensor 722 may be positioned more distally toward the distal curved portion 250 of the pressure-sensing guide wire 708, for example at location 206B or 206C shown in Figure 2B. However, as previously discussed, it may be beneficial to reduce the diameter of the inner core wire to facilitate flexibility in the transition to the distal curved portion 250. Thus, the sensor housing 742 and the pressure sensor 722 may be positioned in the region where the connector tube 730 and / or the core wire 716 transition to a reduced diameter. For example, as shown in Figure 7, the connector tube 730 may have a reduced diameter region 746 at its distal end. The connector tube 730 may be tapered at a tapered portion 754 toward the reduced diameter region 746. The diameter of the proximal end of the core wire 716 may be smaller than the outermost diameter of the connector tube 730, for example, at the distal end or distal region of the connector tube 730. In this configuration, the outer diameter of the sensor housing 742 may be reduced compared to the sensor housing 542.

[0172] Figure 8 is a schematic diagram of another variation of the pressure-sensing guide wire 808. The pressure-sensing guide wire 808 is similar to the pressure-sensing guide wire 708, except that the sensor housing 842 and the pressure sensor 822 may be positioned more distally to the distal curved portion 250 of the pressure-sensing guide wire 808, for example at location 206D shown in Figure 2B. However, as previously considered, it may be beneficial to reduce the diameter of the inner core wire to facilitate flexibility at the transition to the distal curved portion 250. Thus, in the region indicated by reference numeral 206D in the distal curved portion 250, the reduced-diameter portion 826 of the core wire 816 may have a diameter reduced sufficiently to allow the sensor 822 to be positioned between the radially distal coil portion 812a and the reduced-diameter portion 826 of the core wire 816. As shown in Figure 8, the sensor 822 may have another sensor housing 842 positioned around the sensor 822.

[0173] Instead of a sensor housing along the outer tube 810, the pressure guide wire 808 includes a connector 848 extending between coil portions 812a and 812b. The connector 848 may include an opening 852 to allow at least one pressure wire lead 820 to transition from a first area 838a, which is concentric with the outer tube 810 and located within the connector tube 830, to a second area 838b, which is non-coaxial with respect to the longitudinal axis L of the outer tube 810. The opening 852 may be a cut-off portion of thickness or may extend through the entire thickness of the outer tube 810. If the opening 852 extends through the entire thickness of the outer tube 810, the opening 840 may be sealed, for example with an adhesive, to prevent fluid from flowing through the opening to the pressure guide wire.

[0174] Figure 9 is a cross-sectional view of another variation of the pressure-sensing guide wire 908. The pressure-sensing guide wire 908 is similar to the pressure-sensing guide wire 808, except that Figure 9 includes a distal tip 932. The distal tip 932 may include any of the features of the distal tip 632 shown in Figure 6.

[0175] The outer tube 910 comprises an insulating portion 934 and a coil portion 912, which are coupled by a connector 948. The insulating portion 934 encloses at least a portion of the connector tube 930. The insulating portion 934 may comprise a polymer layer, such as PTFE, to electrically isolate the connector tube 930 from the patient during high-frequency pacing. The proximal end 956 of the connector tube 930 may be exposed from the proximal end of the insulating portion 934 for connection to a monitoring device and / or a current generator. Thus, at least the proximal end of the connector tube 930 may not be covered.

[0176] As shown in the illustration, the connector 948 may be a metal tube connecting the insulating portion 934 and the coil portion 912, but in other variations, the connector 948 may be a welded portion joining the insulating portion 934 and the coil portion 912.

[0177] One or more pressure wire leads 920 may be sealed in the inner lumen of the connector tube 930, for example, using an adhesive, to prevent fluid from flowing proximal and to ensure the concentricity of the optical fiber for signal transmission.

[0178] The pressure sensor 922 may be exposed to blood or other fluids through a gap or space in the coil portion 912. The outer tube 910 may also comprise a sensor housing area 924. The sensor housing area may be more rigid than the rest of the coil portion 912. For example, the sensor housing area 924 may be a metal tube dividing the coil portion 912 into two sections. The sensor housing area 924 may be mounted on the distal portion of the first coil section of the coil portion 912 and the proximal portion of the second coil section of the coil portion 912. The sensor housing area 924 may have one or more openings to expose the pressure sensor 922 to blood or other fluids. As another example, the coil portion 912 may comprise two coils welded together to create a reinforced area that acts as the sensor housing area 924.

[0179] III. Heart Valve Evaluation User Interface System Existing user interfaces may be unable to indicate, or may be unable to indicate, the status of heart valves before, during, and / or immediately after the deployment of structural cardiac devices. During structural cardiac procedures, existing user interfaces may be unable to provide one or more pressure curves or indications of heart valve status, such as an index of valve regurgitation or pressure gradient. Furthermore, existing user interfaces for structural cardiac procedures may have limited the ability to interact with the user, such as by a lack of options to allow the user to customize one or more user interfaces. Existing patient monitoring devices and / or display devices may have limited the visual space for presenting indications such as heart valve status, diagnostics, physiological parameters, or other data.

[0180] Therefore, the user interface of the cardiac valve assessment system disclosed herein can be an improvement over existing user interfaces. During structural cardiac procedures, one or more indications of the cardiac valve status may be provided to the clinician via the user interface. The user interface can be constructed to provide information in an efficient manner. Specific graphical representations or indications may be presented or selected by the user, allowing the cardiac valve clinician to quickly access a condition or problem. The systems and technologies described herein allow clinicians to access data more quickly, perform analyses more quickly, and / or interact with one or more user interfaces more quickly than existing graphical user interface systems (for example, by reducing the number of clicks or selections made by the user). The user interfaces described herein can be an improvement over existing user interfaces by providing a more efficient use of limited visual space in small monitoring or display devices. For example, visual indications, graphical representations, and / or combinations thereof can provide information to the user in relation to the cardiac valve status in an efficient manner configured for monitoring or display devices with limited space. Therefore, the systems and technologies described herein can be an improvement over conventional user interfaces.

[0181] As used herein, in addition to its usual meaning, “cardiovascular region” can be broadly defined as the region encompassing the left ventricle, right ventricle, aorta, left atrium, right atrium, vena cava, and / or any part of the heart that is adjacent to or surrounding blood flow pathways (such as ventricles, blood vessels, and pulmonary arteries).

[0182] The cardiac valve assessment systems described herein can advantageously provide indications of cardiac valve conditions, such as pressure gradients or valvular regurgitation indices. In addition to its usual meaning as used herein, “pressure gradient” or “gradient” can mean the degree or measurement of valve narrowing (or stenosis) due to the rise in pressure after the valve. Examples of gradients provided herein include peak-to-peak gradients, area gradients, or instantaneous gradients. A peak-to-peak gradient can indicate the pressure difference between the maximum or locally maximum systolic pressure of a first cardiovascular region (e.g., left ventricle LV) and the maximum or locally maximum systolic pressure of a second cardiovascular region (e.g., aorta Ao). An area gradient can indicate the area between two graphs, such as pressure curves. An instantaneous gradient can indicate the maximum or locally maximum pressure between a first and second cardiovascular region during a cardiac cycle. In addition to its usual meaning as used herein, “valvular regurgitation indices,” “regurgitation indices,” or “regurgitation” can mean a measurement of valve leakage. The calculation of regurgitation may include the pressure difference at the end of the diastolic cycle divided by the systolic pressure or normalized. The calculation of aortic regurgitation can correspond to the following formula: Index of aortic regurgitation = (Aortic diastolic blood pressure - Left ventricular diastolic pressure) / Aortic systolic blood pressure. Other cardiac valve conditions may include cardiac high-frequency pacing. The systems, technologies, and / or graphical user interfaces described herein can provide clinicians with additional data on which treatment / action decisions to make. For example, cardiac valve conditions and / or related user interfaces can provide clinicians with additional information to address valve disease, to change replacement valves during procedures, and / or to make recommendations following valve procedures.

[0183] Regurgitation can occur when blood leaks through the valve to the other side. Regurgitation can be caused by disease of the valve, or, in the case of prosthetic replacement, by improper sealing of the replacement valve to the original valve.

[0184] a. The example user interface Figures 10A–10E, 11A–11C, and 12 depict an example of a cardiac valve evaluation user interface. The cardiac valve evaluation system may be the same as or similar to the diagnostic system 200 described earlier in Figure 2A, or may have similar components to the diagnostic system 200. For convenience, the user interface is described as being presented by the diagnostic system 200 or the monitoring device 204, but other computer systems may present the user interface. The user interface may be presented by the monitoring device 204 described earlier, for example, using data received from the pressure guide wire 208, the pressure-sensing access catheter 20, or the pressure-sensing pigtail catheter 10. Thus, each of the illustrated user interfaces may be output for presentation by electronic hardware as a graphical user interface.

[0185] Each illustrated user interface comprises one or more user interface elements or controls that can be selected by the user. The user interface can enable the reception of user input. The illustrated user interface elements are merely illustrative examples and may differ in other embodiments. For example, the aspects of the user interface may be rearranged from those illustrated and described later, and / or specific aspects may or may not be included. Furthermore, the illustrated user interfaces may be combined or divided into other user interfaces so that similar or identical functionality may be provided. User interfaces in Figures 10A to 10E, such as user interfaces 1000, 1020, 1040, 1060, and / or 1080, may have similar user interface elements and / or capabilities. Furthermore, each element of the user interface may be selected by the user using one or more input options from among several user interface input options, such as mouse, touchscreen input (e.g., finger or pen), or keyboard input.

[0186] Figures 10A to 10E depict example user interfaces that may be presented by the monitoring device 204 described earlier. In Figure 10A, the user interface 1000 may be presented before, during, and / or immediately after a cardiac procedure. The user interface 1000 may include one or more graphs 1002, 1004, 1006, 1008 and one or more physiological parameters 1010, 1012. Graphs 1002, 1004, 1006, 1008 in the example may include, or may be, pressure waves. Graphs 1002, 1004, 1006, 1008 may present pressure values ​​corresponding to measurements from a cardiovascular region. The pressure values ​​may include a series of numerical values ​​of pressure over time. The cardiovascular region may include a portion of the heart (left ventricular LV, right ventricular RV, or mitral valve) and / or blood flow pathways adjacent to a portion of the heart (aorta Ao, vena cava, or pulmonary artery, etc.). One or more graphs 1002, 1004, 1006, 1008, and / or one or more physiological parameters 1010, 1012 may be updated in real time or near real time as pressure measurements are obtained from the patient.

[0187] As illustrated, the user interface 1000 may include a first graph 1002 for a first cardiovascular region such as the aorta (Ao) and a second graph 1006 for a second cardiovascular region such as the left ventricular (LV). Additional graphs 1004, 1008 may accommodate statistical measurements of pressure values ​​from cardiovascular regions, such as mean or arithmetic mean pressure values ​​for the aorta (Ao) or left ventricular (LV). The statistical measurement may be based on a configuration parameter that can be selected by the user and indicates the statistical measurement period, such as the number of heartbeats or the duration of time for calculating the statistical measurement. In some embodiments, one or more graphs 1002, 1004, 1006, 1008 may have indications for pointing to the corresponding cardiovascular region for the graph (for example, graphs 1002 and 1004 for the aorta (Ao) may be colored red, and graphs 1006 and 1008 for the left ventricular (LV) may be colored blue).

[0188] As illustrated, the user interface 1000 may include a first physiological parameter 1010 for a first cardiovascular region such as the aorta (Ao) and a second physiological parameter 1012 for a second cardiovascular region such as the left ventricle (LV). The physiological parameters 1010, 1012 may include statistical measurements of blood pressure such as systolic blood pressure, diastolic blood pressure, and / or mean or arithmetic mean systolic or diastolic blood pressure, or a combination of some of these for a specific cardiovascular region. Physiological parameters of statistical measurements may correspond to additional graphs 1004, 1008.

[0189] The user interface 1000 may include one or more user interface options, such as a recording option 1014. A clinician may select a recording option 1014 to record blood pressure values, other measurements, and / or other values ​​related to a procedure. The clinician can then replay the recorded data. In some embodiments, but not limited to them, a cardiac valve condition, such as an index of gradient or regurgitation, may be presented to the user during the replay mode.

[0190] Figure 10B depicts another user interface 1020. The additional user interface 1020 may be similar to the user interface 1000 in Figure 10A. However, the additional user interface 1020 may include a stop recording option 1022 that allows the user to stop recording patient data. In some embodiments, once stopped, the user may enter a playback mode to view the heart valve condition, such as gradient or regurgitation indicators, but not limited to these.

[0191] Figure 10C shows yet another user interface 1040. The additional user interface 1040 may be similar to the user interface 1000 in Figure 10A. The additional user interface 1040 may include a first graph 1002 and a second graph 1006 similar to the first and second graphs in Figure 10A. However, the additional user interface 1040 may present one or more gradient drawings 1042a, 1042b, 1042c that visually present a gradient measurement between the first peak in the first graph 1002 and the second peak in the second graph 1006. One or more gradient drawings 1042a, 1042b, 1042c may correspond to gradient types such as peak-to-peak gradients.

[0192] The user interface 1040 may include a first numerical value 1046 corresponding to a gradient type, such as a peak-to-peak gradient. The first numerical value 1046 may correspond to the pressure difference between the maximum or locally maximum systolic pressure of a first cardiovascular region (e.g., left ventricular LV) and the maximum or locally maximum systolic pressure of a second cardiovascular region (e.g., aorta Ao). In some embodiments, the first numerical value 1046 may include a statistical measurement, such as the arithmetic mean or average of the pressure difference between the maximum or locally maximum systolic pressures over multiple heartbeat cycles. As illustrated, the first numerical value 1046 (here 28) may be a statistical measurement of peak-to-peak measurements over multiple heartbeats, corresponding to the peak-to-peak measurements 1042a, 1042b, and 1042c of the three graphs.

[0193] The user interface 1040 can present one or more regurgitation diagrams 1044a, 1044b, 1044c. As illustrated, one or more regurgitation diagrams 1044a, 1044b, 1044c can visually present a measurement of regurgitation between a first point in the first graph 1002 and a second point in the second graph 1006. One or more regurgitation diagrams 1044a, 1044b, 1044c can correspond to the calculation of the pressure difference at the end of the diastolic cycle divided by or normalized by the systolic pressure (here, aortic systolic blood pressure) (here, left ventricular LV end-diastolic pressure from aortic A end-diastolic blood pressure).

[0194] The user interface 1040 may include a second numerical value 1048 corresponding to an index of regurgitation. The second numerical value 1048 may include the pressure difference at the end of the diastolic cycle divided by the systolic pressure or normalized. In some embodiments, the second numerical value 1048 may include a statistical measurement, such as the arithmetic mean or mean regurgitation over multiple heartbeat cycles. As illustrated, the second numerical value 1048 (here 22) may be a statistical measurement of the calculation of regurgitation over multiple heartbeats corresponding to three regurgitation depictions 1044a, 1044b, and 1044c.

[0195] The user interface 1040 may include an electrocardiogram (ECG) recording graph 1050. The ECG recording graph 1050 can be made unavailable or available by the user. The ECG recording graph 1050 can also be removed or omitted from the user interface 1040. Although not shown, in some embodiments, if the ECG recording graph 1050 is removed or omitted, the pressure graph display unit 1051 can be enlarged in the user interface 1040.

[0196] The user interface 1040 may include a playback control unit 1052 and a gradient selection unit 1056. As shown, the playback control unit 1052 can present the time (here, 0:01:18) and the current playback position 1054. In some embodiments, the user can interact with the playback control unit 1052 to fast-forward or rewind the playback of one or more graphs and corresponding indications of heart valve conditions. The user can change the gradient of the user interface 1040 by selecting the gradient selection unit 1056, thereby causing the updated user interface to be presented instead of the current user interface 1040.

[0197] Figure 10D shows yet another user interface 1060. The additional user interface 1060 may be similar to the user interface 1040 in Figure 10C. In addition to other similar user interface elements, the additional user interface 1060 may include a first graph 1002 and a second graph 1006 similar to the first and second graphs in Figure 10C. However, the additional user interface 1060 may present one or more gradient drawings 1062a, 1062b, 1062c that visually present the gradient measurement between a first point in the first graph 1002 and a second point in the second graph 1006. One or more gradient drawings 1062a, 1062b, 1062c of the additional user interface 1060 may be presented in accordance with user selection, such as the user selection of the gradient type selection unit 1056 in Figure 10C.

[0198] One or more gradient descriptions 1062a, 1062b, 1062c may correspond to gradient types such as instantaneous gradients. Instantaneous gradient descriptions 1062a, 1062b, 1062c may indicate the maximum or locally maximum pressure difference between a first cardiovascular region and a second cardiovascular region in a heart cycle. User interface 1060 may include numerical values ​​1064 (here 64) corresponding to gradient types such as instantaneous gradients. Numerical values ​​1064 may indicate the maximum or locally maximum pressure difference between a first cardiovascular region (e.g., left ventricle LV) and a second cardiovascular region (e.g., aorta Ao) in a heart cycle. In some embodiments, numerical values ​​1064 may include statistical measurements, such as the arithmetic mean or the maximum or locally maximum pressure difference of the mean over multiple heart cycles. As illustrated, the numerical value 1064 could be a statistical measurement of the instantaneous gradient for multiple heartbeats, corresponding to the instantaneous measurements 1062a, 1062b, and 1062c in the three graphs.

[0199] Figure 10E shows yet another user interface 1080. The additional user interface 1080 may be similar to the user interface 1040 in Figure 10C. In addition to other similar user interface elements, the additional user interface 1080 may include a first graph 1002 and a second graph 1006 similar to the first and second graphs in Figure 10C. However, the additional user interface 1080 may present one or more gradient drawings 1082a, 1082b, 1082c that visually present the area between the first graph 1002 and the second graph 1006. One or more gradient drawings 1082a, 1082b, 1082c of the additional user interface 1080 may be presented in response to user selections, such as one or more user selections in the gradient type selection section 1056 in Figure 10C.

[0200] One or more gradient descriptions 1082a, 1082b, 1082c may correspond to gradient types, such as area gradient types. Area gradient descriptions 1082a, 1082b, 1082c may indicate the pressure difference between a first cardiovascular region and a second cardiovascular region. User interface 1080 may include numerical values ​​1084 (here 56) corresponding to gradient types, such as area gradient types. Numerical values ​​1084 may indicate the area between two graphs corresponding to a first cardiovascular region (e.g., left ventricle LV) and a second cardiovascular region (e.g., aorta Ao). In some embodiments, numerical values ​​1084 may include statistical measurements, such as the arithmetic mean or average area between two graphs or pressure curves for multiple heartbeat cycles. As illustrated, numerical values ​​1084 may be statistical measurements of area gradients for multiple heartbeats corresponding to instantaneous measurements 1082a, 1082b, 1082c of three graphs.

[0201] Figures 11A to 11C depict additional example user interfaces that may be presented by the monitoring device 204 described earlier. User interfaces 1100, 1120, and 1140 in Figures 11A, 11B, and 11C may be similar to user interfaces 1040, 1060, and 1080 in Figures 10C, 10D, and 10E, respectively. Specifically, user interfaces 1100, 1120, and 1140 in Figures 11A, 11B, and 11C may present alternative gradient depictions to the gradient depictions of user interfaces 1040, 1060, and 1080 in Figures 10C, 10D, and 10E, respectively. Furthermore, user interfaces 1100, 1120, and 1140 in Figures 11A, 11B, and 11C can depict user interfaces that present the heart valve status for the mitral valve.

[0202] In Figure 11A, the user interface 1100 may include a gradient plot 1102. The gradient plot 1102 may be for a peak-to-peak gradient, which may be similar to the peak-to-peak gradient in Figure 10C. However, instead of visualizing the measurements between the two peaks, the gradient plot 1102 may plot one or more pressure values ​​corresponding to the peak-to-peak gradient in graphical form. The advantage of the gradient plot 1102 in Figure 11A is that it allows clinicians to quickly review the relative peak-to-peak pressure changes over time, which may include past and present measurements.

[0203] The backflow diagram 1104 in Figure 11A may be similar to the backflow diagrams 1044a, 1044b, and 1044c in Figure 10C. However, similar to the gradient diagram 1102, the backflow diagram 1104 may depict one or more pressure values ​​corresponding to valve backflow in graphical form instead of visualizing the measurement between two points.

[0204] As seen in Figure 11B, the user interface 1120 may include another gradient depiction 1122. The gradient depiction 1122 may be for an instantaneous gradient type, which may be similar to the instantaneous gradient type in Figure 10D. However, instead of visualizing the measurement between two points, the gradient depiction 1122 can depict one or more pressure values ​​corresponding to a peak-to-peak gradient in graphical form. Similar to the gradient depiction 1102 in Figure 11A, the advantage of the gradient depiction 1122 in Figure 11B is that it allows clinicians to quickly reconsider relative instantaneous pressure changes over time, which may include past and present measurements.

[0205] As seen in Figure 11C, the user interface 1140 may include another gradient depiction 1142. The gradient depiction 1142 may be for an area gradient type, which may be similar to the area gradient type in Figure 10E. However, as an alternative to or addition to depicting the area between the two graphs as an exclusive visualization, the gradient depiction 1142 may depict one or more pressure values ​​corresponding to the area gradient in graphical form. Similar to the gradient depiction 1102 in Figure 11A, the advantage of the gradient depiction 1142 in Figure 11C is that it allows clinicians to quickly reconsider relative pressure changes over time, which may include past and present measurements.

[0206] Figure 12 depicts a configuration user interface 1200 for a cardiac valve assessment system. A clinician can use the configuration user interface 1200 to configure one or more user interfaces. The configuration user interface 1200 allows the clinician to select the type of procedure, the default type of regurgitation, the time scale, the pressure scale, and / or other customizable user interface options. The configuration user interface 1200 may include a statistical measurement period selection unit 1202 that allows the user to select the number of heartbeats for the calculation of statistical measurements.

[0207] b. User Interface Generation Process Figure 13 shows an example user interface generation process 1300. While process 1300 is described in relation to a heart valve evaluation system such as system 200 in Figure 2A, or system 1400 in Figure 14 (described later), any system configured to perform the process in any order is within the scope of this disclosure. Process 1300 may be performed by various components of the system in Figure 2A, or system 1400 in Figure 14 (described later), including the monitoring device 204. Depending on the embodiment, process 1300 may include fewer or additional blocks, and / or the blocks may be performed in a different order than those shown. Other embodiments of process 1300 may include fewer blocks than those shown, or the blocks may be performed in a different order than those shown.

[0208] Beginning in block 1302, pressure values ​​can be received. Specifically, the monitoring device 204 can receive pressure values. The monitoring device 204 can receive a first set of pressure values ​​and a second set of pressure values. Each pressure value from the first set of pressure values ​​can correspond to a first signal received from a first pressure sensor measuring a first cardiovascular region, such as a first part of the heart. Each pressure value from the second set of pressure values ​​can correspond to a second signal received from a second pressure sensor measuring a second cardiovascular region, such as a blood flow passage adjacent to the first part of the heart. Thus, the monitoring device 204 can determine the first and second sets of pressure values ​​from the first and second sensors, respectively. As previously described in Sections I and / or II, the pressure sensor may be incorporated into a therapeutic device such as a pressure guide wire, access catheter, pigtail catheter, or a cardiac valve inflation balloon or cardiac valve delivery device adapted to sense pressure, or other pressure sensing device. Further details regarding receiving pressure values ​​may be described later with respect to process 1500 in Figure 15, such as with respect to blocks 1502 and / or 1504 of process 1500.

[0209] In block 1304, configuration parameters may be received. Specifically, the monitoring device 204 can receive configuration parameters. Example configuration parameters may include the number of heartbeats or the default gradient type presented in the user interface. Further details regarding configuration parameters are described in more detail earlier in relation to Figure 12.

[0210] In block 1306, a user selection may be received. An example user selection may be a change in gradient type. The user may select the gradient type selection unit 1056 in Figure 10C to change between gradient types, such as the instantaneous gradient type in Figure 10D or the area gradient type in Figure 10E. Additional user selections may be changes to the configuration parameters of the configuration user interface 1200 described earlier in Figure 12. For example, a user selection may be a user heart rate selection. A user heart rate selection may specify the number of heartbeats that may be used for statistical measurement (e.g., two, three, or four heartbeats). A user heart rate selection may also include the selection of one or more specific heartbeats. For example, the user may interact with the user interface described herein to select a portion of the graph corresponding to a specific heartbeat, and / or select an identifier for a specific heartbeat.

[0211] In block 1308, a heart valve state can be determined. As described herein, an example heart valve state may be a regurgitation index or gradient pressure. The monitoring device 204 can determine the heart valve state based on the data from blocks 1302, 1304, and 1306. For example, the monitoring device 204 can calculate a specific heart valve state from received pressure values, depending on configuration parameters or user selections that can specify a specific gradient type, the number of heartbeats for calculation, and / or specific heartbeats to use or exclude. As described herein, the number of heartbeats can be used to calculate statistical measurements for a specific heart valve state, such as a regurgitation index or gradient. The monitoring device 204 can detect high-frequency pacing from either a first set or a second set of pressure values, for example, by detecting that the number of heartbeats exceeds a threshold time period. Additional details regarding the determination of the heart valve state are described later in Section IV, such as with respect to process 1500 in Figure 15. Some of the blocks in process 1500 in Figure 15 may further describe the determination of the heart valve state, such as blocks 1504, 1506, 1508, and 1510.

[0212] In block 1310, a user interface may be presented. The monitoring device 204 may present a user interface. An example user interface has been previously described in relation to Figures 10A-10E and 11A-11C. The first presented user interface may include a first graph based at least partially on a first set of pressure values ​​and a second graph based at least partially on a second set of pressure values. The first presented user interface may correspond to any of the user interfaces 1040, 1060, 1080, 1100, 1120, and 1140 in Figures 10C, 10D, 10E, 11A, 11B, and 11C, respectively. The first presented user interface may include a depiction of a gradient indicating the gradient of the valve, such as a peak-to-peak gradient, an instantaneous gradient, and / or an area gradient. For example, the first gradient plot can visually depict the region between the first graph and the second graph (e.g., gradient plots 1082a, 1082b, 1082c in Figure 10E). The presented region can indicate the pressure difference between the first cardiovascular region and the second cardiovascular region. The first user interface may include a numerical value indicating the amount of valve regurgitation (e.g., the second numerical value 1048 in Figure 10C). The first user interface may include a regurgitation plot (e.g., regurgitation plots 1044a, 1044b, 1044c in Figure 10C) that visually presents the measurement of regurgitation between the first point in the first graph and the second point in the second graph. Thus, the measurement of regurgitation can indicate the quantitative regurgitation of the valve. The first user interface may also include a numerical value for the first gradient of the valve by statistical measurement (e.g., the first numerical value 1084 in Figure 10E, which may be the mean or arithmetic mean gradient value). The first user interface may also include an electrocardiogram recording graph, which is described in more detail earlier in relation to Figure 10C. In some embodiments, the first user interface may present a high-frequency pacing warning if high-frequency pacing is detected.

[0213] In some embodiments, the first user interface may include multiple numerical values ​​for different gradient types in the same graph display. For example, two or more numerical values ​​may be selected from numerical values ​​for peak-to-peak gradients, numerical values ​​for instantaneous gradients, and / or numerical values ​​for area gradients, and may be presented simultaneously in the same graph display.

[0214] As illustrated, after the execution of the present block 1310, the previous block may be revisited to receive additional pressure value data, user selection, and / or update configuration parameters to update one or more user interfaces. For example, the monitoring device 204 may receive a user selection for a second gradient type (such as a peak-to-peak gradient) via the first user interface. Thus, the monitoring device 204 may present a second user interface for the second gradient type (such as a peak-to-peak gradient) instead of the first user interface. The second user interface may include a first graph, a second graph, and a second gradient depiction (such as gradient depictions 1042a, 1042b, 1042c in Figure 10C) that visually presents the gradient measurement between the first peak in the first graph and the second peak in the second graph.

[0215] The user can make any number of changes to the user interface. For example, a selection of a different user interface may be received for a third gradient type (such as an instantaneous gradient type). Thus, the monitoring device 204 can present a third user interface for a third gradient type (such as an instantaneous gradient type) instead of the second user interface. The third user interface may include a first graph, a second graph, and a third gradient depiction (such as gradient depictions 1062a, 1062b, 1062c in Figure 10D) that visually presents a second gradient measurement between a first point in the first graph and a second point in the second graph. While specific orders for changing gradient types are described herein, any order of changing gradient types may be accepted by the heart valve evaluation system.

[0216] IV. Cardiac valve evaluation systems and methods The systems and methods described herein can be used to evaluate heart valves. Pressure valves can be used to evaluate valves. Valves can be diagnosed using various signal processing methods involving pressure gradients across the valve. Pressure gradients across the valve during systole can indicate pressure loss caused by blood flowing through the valve, which can indicate limits in blood flow. For example, pressure gradients at the end of cardiac diastole after the valve is closed can indicate the amount of blood leaking through the valve while it is closed. Normalizing or dividing this gradient by systolic pressure from a cardiovascular region such as the aorta, as described herein, may be called regurgitation. Various techniques described herein, but not limited to, can be used to improve the accuracy of valve evaluation or diagnostic methods, including pressure sensor calibration, waveform adjustment, feature detection, and / or valve state generation.

[0217] a. Overview of the heart valve evaluation system and method Figure 14 shows a block diagram of the heart valve system 1400. In Figure 14, the heart valve evaluation environment 1402 comprises an input unit 1404 for pressure signals, etc., a heart valve evaluation system 1400, and an output unit 1406 for valve status, valve diagnostic indicators, and / or waveforms. The example waveform may include time-series data, such as a series of pairs of pressure and timestamp values. The heart valve evaluation system 1400 may be similar to, or be embodied in, a monitoring device 204, and / or components of the heart valve evaluation system 1400 may be embodied in the monitoring device 204. The pressure signal 1406 can be received from one or more pressure sensors described herein, such as a pressure guide wire 208, a pressure-sensing access catheter 20, or a pressure-sensing pigtail catheter 10.

[0218] The cardiac valve evaluation system 1400 may include a calibration service 1408, a waveform adjustment service 1410, a feature detection service 1412, and / or a valve state determination service 1414. The calibration service 1408 can calibrate one pressure sensor against other pressure sensors. The waveform adjustment service 1410 can adjust one or more pressure waveforms so that two or more pressure waveforms can be generally synchronized. The feature detection service 1412 can detect one or more features from the pressure waveform, such as detection of systole, diastole, dicrotic notch, end of cardiac diastole, and / or start of cardiac systole. The valve state determination service 1414 can determine one or more valve states. The valve state determination service 1414 may include an index calculation unit 1416 and / or a gradient calculation unit 1418. The index calculation unit 1416 can generate indices such as an index of valve regurgitation. The gradient calculation unit 1418 can generate pressure gradients and / or statistical measurements of pressure gradients. Generated output data 1406, such as valve status, valve diagnostic indicators, and / or waveforms, may be provided to a user interface as described herein, or to other devices or systems.

[0219] Figure 15 shows an example of a valve evaluation process 1500. While process 1500 is described in relation to a cardiac valve evaluation system such as system 200 in Figure 2A or system 1400 in Figure 14, any system configured to perform the process in any order is within the scope of this disclosure. Process 1500 may be performed by various components of the system in Figure 2A or system 1400 in Figure 14, as discussed herein, including the monitoring device 204. Depending on the embodiment, process 1500 may include fewer or additional blocks, and / or the blocks may be performed in a different order than those shown. Other embodiments of process 1500 may include fewer blocks than those shown, or the blocks may be performed in a different order than those shown.

[0220] Beginning in block 1502, a pressure value or signal may be received or determined. Specifically, the heart valve evaluation system 1400 may receive a pressure signal from a pressure sensor such as a pressure guide wire 208, a pressure-sensing access catheter 20, or a pressure-sensing pigtail catheter 10. From the received pressure signal, the heart valve evaluation system 1400 may determine a first set of pressure values ​​and a second set of pressure values. Each pressure value from the first set of pressure values ​​may correspond to a first signal received from a first pressure sensor measuring a first cardiovascular region. Each pressure value from the second set of pressure values ​​may correspond to a second signal received from a second pressure sensor measuring a second cardiovascular region which may be the same as or different from the first cardiovascular region. The heart valve evaluation system 1400 may determine the first and second sets of pressure values ​​from the first and second sensors, respectively. As previously described in Sections I and / or II, the pressure sensor may be incorporated into a pressure guide wire or other pressure-sensing device. In some embodiments, the first and second pressure sensors may be located in the same or different cardiovascular regions, such as where calibration is performed. In such cases, the process can proceed to block 1504.

[0221] Calibration may be performed in block 1504. Calibration service 1408 can perform the calibration. A second sensor may be calibrated relative to the first sensor to determine a more accurate pressure measurement. Similarly, the first sensor may be calibrated relative to the second sensor to determine a more accurate pressure measurement. In some embodiments, each of the first and second sensors may be calibrated together. The pressure value determined from the second sensor may be adjusted based on the calibration. Calibration of the first and second sensors may result in the generation of one or more calibration parameters. One or more calibration parameters can be used to adjust one or more pressure values ​​determined from the calibrated pressure sensors. Additional details regarding calibration are described later in more detail with respect to process 1600 in Figure 16 and / or process 2700 in Figure 27. As used herein, the terms “calibration” and “equalization” are interchangeable.

[0222] The process can return to block 1502. Once calibration is complete, one or more pressure sensors can be moved to different cardiovascular regions, and additional pressure signals can be received in block 1502. Pressure signals may be received from two or more pressure sensors located in different cardiovascular regions. Examples of different cardiovascular regions include, but are not limited to, adjacent blood passages such as both sides of a heart valve, the left ventricle and the aorta, the left ventricle and the left atrium, the right ventricle and the pulmonary artery, the right atrium and the right ventricle, the vena cava and the right atrium. The heart valve evaluation system 1400 can determine first and second sets of pressure values ​​from the pressure signals, for example, by applying the determined calibration parameters.

[0223] In block 1506, waveform adjustment may be performed. Since some valve conditions (such as diagnostics) may be based on intracardiac waveform analysis in which a specific portion of the heart cycle may be used, it may be important to adjust one or more pressure waveforms to generally synchronize or align two or more pressure waveforms. Waveform adjustment can accommodate one or more time lags in the waveforms so that corresponding features of the waveforms are aligned. In some embodiments, the waveform adjustment service 1410 can automatically adjust one or more waveforms. In other embodiments, some aspects of waveform adjustment may include receiving user input, such as an operator manually adjusting one or more waveforms.

[0224] The waveform adjustment service 1410 can adjust the phase between one or both pressure waveforms by adding a delay to one or both of the pressure waveforms during installation, maintenance, or use with a particular patient. This technique can take the setup process during installation or maintenance as representing the setup process during a procedure such as TAVI. For example, a time delay in the aortic pressure signal can represent a delay in the aortic pressure line induced during a TAVI procedure. The waveform adjustment service 1410 can adjust the phase for each specific patient.

[0225] The waveform adjustment service 1410 may include, or be able to communicate with, an automatic phase delay recognition system that can advise the operator to match and adjust the phase delay between both pressure signals. The waveform adjustment service 1410 can match such time delays while equalization is required or while equalization is being performed, such as when both pressure signals have the same origin (e.g., when they are located in the same place to experience similar pressures) or when the pressure signals are from different locations.

[0226] The waveform adjustment service 1410 can detect a phase delay based on the time delay between one or more pressure waveform features. Pressure waveform features may include one or more of the relative positions of systolic pressure, dicrotic notches, or the end of cardiac diastole. The waveform adjustment service 1410 can use a feature of the relative position of the maximum slope of the boundary of the rise of systole, which may be a reliable feature.

[0227] Alternatively, the waveform adjustment service 1410 can systematically adjust for time delays when pressure equalization is required. Similar to techniques for detecting phase delays, time adjustment can be measured by comparing the relative positions of features in a particular pressure waveform. For example, the waveform adjustment service 1410 can delay the timing of pressure sampling during equalization based on recognition of pressure waveform features. The waveform adjustment service 1410 can use the cross-correlation between both signals, that is, by calculating the correlation of one signal with respect to the other signal while the time difference is present. The time difference can consequently increase, or even maximize, the correlation between both signals, which can accommodate time differences that may be added to the pressure signal or other factors.

[0228] In block 1508, feature detection may be performed. Feature detection service 1412 can perform feature detection. Examples of features that can be detected from the pressure waveform may include systole, diastole, dicrotic notch, end of cardiac diastole, and / or start of cardiac systole. Additional details regarding feature detection are described further below in relation to process 1900 in Figure 19.

[0229] In block 1510, the heart valve state can be determined. The valve state determination service 1414 can determine the valve state. Specifically, the index calculation unit 1416 can generate indices such as an index of valve regurgitation, and the gradient calculation unit 1418 can generate pressure gradients and / or statistical measurements of pressure gradients. The index calculation unit 1416 and / or the gradient calculation unit 1418 can use the calibrated or adjusted waveforms or detected features of the preceding block to generate the valve state. The index calculation unit 1416 can calculate the index of regurgitation based at least in part on a first subset of a first set of pressure values ​​corresponding to systole or diastolic, and a second subset of adjusted pressure values ​​corresponding to systole or diastolic. For example, the index calculation unit 1416 can calculate the index of regurgitation using the following formula: Index of aortic regurgitation = (Aortic diastolic blood pressure - Left ventricular diastolic pressure) / Aortic systolic blood pressure. The gradient calculation unit 1418 can calculate the gradient value at least partially based on the difference between a first subset of pressure values ​​during systole and a second subset of adjusted pressure values ​​during systole (such as the area gradient value, peak-to-peak gradient value, and / or instantaneous gradient value, which are described in more detail earlier in Section III). Additional details regarding the determination of the valve state are described in more detail earlier in Section III.

[0230] In block 1512, the heart valve status may be presented to the user interface. The heart valve evaluation system 1400 and / or monitoring device 204 can present the heart valve status. Further details regarding the presentation of valve status are described in more detail earlier with respect to block 1310 in Figure 13 and the user interfaces in Figures 10A-10E and 11A-11C.

[0231] b. Pressure sensor calibration As described herein, a first sensor can be calibrated against a second sensor to determine a more accurate pressure measurement, which may also be called equivalence. For example, a pressure guide wire may be located at or near a valve, along with other pressure instruments. Other pressure instruments may be a catheter, pigtail, or other device having a lumen used to deliver pressure to a valve and connected to a pressure transducer. The pressure instrument may be another pressure guide wire or a catheter with a pressure sensor at its tip. The pressure guide wire and pressure instrument are positioned to measure the same pressure. Pressure sensors may be positioned in the same cardiovascular region, such as the aorta, in the ventricle, in the atrium, or at some other location. It is understood that pressure sensors at the same location should display the same pressure, but there may be a difference between the first and second pressures (such as between aortic pressure Pa and distal pressure Pd). Therefore, at the same location, one pressure wire can be calibrated against the other pressure sensor.

[0232] The systems and methods described herein for calibrating pressure sensors can improve the accuracy of pressure instruments. For example, as previously stated, even when two pressure instruments are positioned in the same cardiovascular region, there may be differences in pressure based on the proximal or distal location of each pressure instrument. Furthermore, differences in pressure may arise from other factors, such as different types of devices among multiple pressure instruments. Therefore, the systems and methods described herein for calibration can improve the technology of pressure instruments by providing more accurate pressure readings.

[0233] Figure 16 shows an example calibration process 1600. While process 1600 is described in relation to a heart valve evaluation system such as system 200 in Figure 2A or system 1400 in Figure 14, any system configured to perform the process in any order is within the scope of this disclosure. Process 1600 may be performed by various components of the system in Figure 2A or system 1400 in Figure 14, as discussed herein, including the monitoring device 204. Depending on the embodiment, process 1600 may include fewer or additional blocks, and / or the blocks may be performed in a different order than those shown. Other embodiments of process 1600 may include fewer blocks than those shown, or the blocks may be performed in a different order than those shown.

[0234] Beginning in block 1602, one or more calibration pressure values ​​may be determined from one or more pressure sensors. Calibration service 1600 can determine one or more calibration pressure values ​​from one or more pressure sensors. Calibration service 1600 can receive a first calibration pressure value corresponding to a first calibration signal received from a first pressure sensor measuring the cardiovascular region, and a second calibration pressure value corresponding to a second calibration signal received from a second pressure sensor measuring the same cardiovascular region. Calibration service 1600 can receive a first set of calibration pressure values ​​determined from the first pressure sensor and a second set of calibration pressure values ​​determined from the second pressure sensor.

[0235] In block 1604, calibration parameters can be calculated. Calibration service 1600 can calculate one or more calibration parameters. Calibration service 1600 can use one or more techniques to calculate calibration parameters such as offset or gain (G). Calibration service 1600 can determine offset or gain (G). To calculate the offset, calibration service 1600 can use the following offset formula, i.e., P1 = P2 + offset, where P1 can be Pd and P2 can be Pa. The offset may be used by calibration service 1600 to determine that the pressure is equal between two pressure sensors (e.g., mean pressure). Additionally or alternatively, calibration service 1600 may adjust the gain (G) of one of the pressure sensors so that the pressure between the two sensors (e.g., mean pressure) is equal. The calibration service 1600 can use the following gain formula to calculate the gain (G), namely P1 = G * P2, where P1 can be Pd and P2 can be Pa.

[0236] Calibration service 1600 can use linear fitting to determine calibration parameters. The first and second sets of pressure values ​​may be or contain the first vector or the second vector, respectively. Calibration service 1600 can determine a linear fitting between the first vector and the second vector. The first vector may correspond to [P1] (e.g., [Pd]), and the second vector may correspond to [P2] (e.g., [Pa]). Calibration service 1600 can use the following offset formula, namely [P1] = K * [P2] + b, to calculate the offset. Calibration service 1600 can apply linear fitting between multiple pressure measurements of one pressure sensor relative to the other pressure sensor to determine calibration parameters K and b. Calibration of linear fitting may be desirable when both pressure measurements are equal when positioned in a cardiac chamber, such as the ventricle. In contrast to aortic pressure, ventricular (and atrial) pressures vary over a wide range of pressures, from almost venous pressure to aortic systolic pressure (and even higher pressures considering pressure loss before and after the aortic valve), thus minimizing the risk of obtaining a linear fit with a significant offset (b). [P1] can correspond to a vector containing multiple P1 pressure values ​​(e.g., Pd), and [P2] can correspond to a vector containing multiple P2 pressure values ​​(e.g., Pa). The pressure measurements that the calibration service 1600 can use to calculate the linear fit can be a subset of pressure measurements and may include only systolic pressure measurements, diastolic pressure measurements, or other parts of the heart cycle.

[0237] In block 1606, calibration parameters may be applied. Calibration service 1600 can apply one or more calibration parameters to a pressure value. Calibration service 1600 can apply an offset, gain (G), or linear adjustment parameters (K and b) to one or more pressure values ​​to determine one or more adjusted pressure values.

[0238] c. Feature detection The cardiac valve evaluation system 1400 may rely on determining the phase of the cardiac cycle to determine valve conditions, such as an index of regurgitation. Thus, the cardiac valve evaluation system 1400 may detect one or more features, but is not limited to, systole, diastole, dichroic notch, end of diastole, and / or onset of systole. A dichroic notch is a feature that can indicate a phase transition from diastole to systole. The end of diastole or the onset of systole is another feature that can be detected. The end of diastole can be identified using an electrocardiogram (ECG). In some embodiments, it may be desirable to identify the end of diastole using pressure, as ECG signals may not be available or may often be incomplete. The transition from diastole to systole is often not clearly distinguishable, as it may be completely rounded and / or the transition may also include various pressure features that may result in improper localization. The cardiac valve evaluation system 1400 may rely on features such as regions of rising systolic pressure. The heart valve evaluation system 1400 can identify the location of the maximum or locally maximum slope of the portion of systolic pressure increase, which may be more reliable than other features. Specifically, the heart valve evaluation system 1400 can identify the location of the maximum slope of the conditioned pressure signal.

[0239] Figure 17 depicts the waveform analysis environment 1700. The waveform analysis environment 1700 includes a first set 1702 of pressure data points and a second set 1704 of pressure data points. The heart valve evaluation system 1400 can analyze the data points in environment 1700 to detect dicrotic notch features. The heart valve evaluation system 1400 can detect dicrotic notch features by calculating and identifying data points with the smallest angle formed with nearby data points. An example of angle calculation is shown in Figure 17. With respect to the first set 1702 of data points, the heart valve evaluation system 1400 can obtain angle α(i) by calculating the angle formed by a first line extending from the center point P(i) and the preceding point P(i-1) and a second line extending from the same center point P(i) and the succeeding point P(i+1). With respect to the first set 1702 and the second set 1704 of data points, the angle α(i+1) around point P(i+1) may be smaller than the angle α(i) around P(i). Therefore, the heart valve evaluation system 1400 can identify a dicrotic notch feature at point P(i+1). In this example, the angle is calculated using adjacent points, but the technique may include the use of non-adjacent points. In some embodiments, the technique may include the use of n more data points (such as 2 or 3 more data points) for calculating the line formed in part of the angle. Depending on the embodiment, the signals for the data points may or may not be pre-conditioned.

[0240] Figure 18 depicts another waveform analysis environment 1800. The cardiac valve evaluation system 1400 can analyze data points in environment 1800 to detect the end of cardiac diastole and / or the start of cardiac contraction. Environment 1800 may include waveform 1806. A slope 1802 extending from the position of the maximum or locally maximum slope of the rising portion of cardiac contraction 1801 is shown in Figure 18. The cardiac valve evaluation system 1400 can track a horizontal line 1804 intersecting the minimum or locally minimum pressure value 1803. The intersection 1805 between slope 1802 and horizontal line 1804 can provide a reliable position for an intermediate position in the transition from the end of cardiac diastole to the start of cardiac contraction. In some embodiments, when using aortic pressure to identify the end of cardiac diastole or the start of cardiac contraction, a more accurate positioning of the end of cardiac diastole can be obtained by shifting the position by a predetermined time period 1807. The end of cardiac diastole 1807 is obtained by moving the crossover 1805 by only 40–100 ms. In some embodiments, a positional movement of 60 ms can provide a good estimate of the end of cardiac diastole. The cardiac valve evaluation system 1400 may use other techniques, such as moving the crossover by a percentage of the heart cycle, such as between 8%–12% or 5%–8%.

[0241] The technique described herein may be adapted to identify the end of cardiac diastole when using aortic pressure. The technique may be adapted when the pressure being treated is ventricular pressure. Ventricular pressure can result in a more accurate determination of the end of cardiac diastole because it does not require moving the position of intersection 1805. Once the position of the first intersection 1805 is determined, a more accurate determination of the end of cardiac diastole may include changing the slope extending from the position of maximum slope to a new slope extending from a position located between the position of maximum slope and the first intersection 1805. Specifically, the determination of the end of cardiac diastole may include changing the slope extending from the position of maximum slope to a new slope extending from a position closer to the first intersection 1805. The new slope extending from the position closer to the first intersection 1805 may then be extended to intersect the horizontal line. The new intersection may be found and used as the end of cardiac diastole.

[0242] Figure 19 shows the feature detection process 1900. While process 1900 is described in relation to a heart valve evaluation system such as system 200 in Figure 2A or system 1400 in Figure 14, any system configured to perform the process in any order is within the scope of this disclosure. Process 1900 may be performed by various components of the system in Figure 2A or system 1400 in Figure 14, as discussed herein, including the monitoring device 204. Depending on the embodiment, process 1900 may include fewer or additional blocks, and / or the blocks may be performed in a different order than those shown. Other embodiments of process 1900 may include fewer blocks than those shown, or the blocks may be performed in a different order than those shown.

[0243] Starting in block 1902, the signal can be conditioned. The heart valve evaluation system 1400 can condition the signal. The heart valve evaluation system 1400 can filter the pressure signal, for example, by convolving the signal with a window. The window can be square or other shapes, and the period can be two or more samples. Conditioning the signal may be preferable in certain situations, such as finding the position of maximum tilt, because there may be oscillatory features caused by bubbles or other factors.

[0244] In block 1904, a dichroic notch feature may be detected. Feature detection service 1412 can detect the dichroic notch feature. Various techniques can be used to determine the dichroic notch feature. Feature detection service 1412 detects one of the pressure signals Second floor The derivative can be calculated, and the location of the zero crossing can be identified. More specifically, the feature detection service 1412 takes a first set of pressure values ​​from Second derivative It is possible to calculate, Second derivative Based at least partially on this, zero-crossing points can be identified, and these zero-crossing points correspond to a first dichroic notch feature. These techniques can enable the localization of dichroic notch features when there is no distinct notch, i.e., when there is no notch visible in the graphical representation of the pressure waveform itself. When a distinct notch is present, i.e., when the notch contains a short returning pressure signal feature visible in the graphical representation of the pressure waveform, the feature detection service 1412 can look for the very nearest first derivative zero-crossing point. These techniques can be implemented in unconditional pressure signals, but may also be implemented in conditioned pressure signals.

[0245] The feature detection service 1412 can detect dichroic notch features by calculating and identifying data points with the smallest angle formed with nearby data points. The feature detection service 1412 can calculate a first angle for a first point from a set of pressure values, at least partially based on a first preceding point and a first succeeding point. The feature detection service 1412 can calculate a second angle for a second point from a first set of pressure values, at least partially based on a second preceding point and a second succeeding point. The feature detection service 1412 can determine that the second angle is smaller than the first angle and can identify the second point as the first dichroic notch feature. Additional details regarding the detection of dichroic notch features are described earlier in relation to Figure 17.

[0246] In block 1906, features of the end of cardiac diastole or features of the start of cardiac contraction can be detected. Feature detection service 1412 can detect features of the end of cardiac diastole or features of the start of cardiac contraction. Feature detection service 1412 can identify a first subset of rising pressure values ​​from a first set of pressure values. Feature detection service 1412 can identify a locally minimum pressure value from a first set of pressure values. Feature detection service 1412 can determine the tangent from the first subset. Next, feature detection service 1412 can identify a horizontal line that intersects the locally minimum pressure value, and can identify a first intersection between the tangent and the horizontal line. Feature detection service 1412 can identify a first point from the first set of pressure values ​​as the end of a first diastole or the start of a first systole, at least in part based on the first intersection. Identifying the first point may further include adjusting the first intersection by a predetermined time period. The given time period may be approximately 60 milliseconds, or may include approximately 60 milliseconds. The given time period may include a range of approximately 40 milliseconds to approximately 100 milliseconds. Identifying the first point may further include adjusting the first crossover in percentages of the heart rate cycle. The percentage may include a range of approximately 8 percent to 12 percent of the heart rate cycle, or may include a range of approximately 8 percent to 12 percent of the heart rate cycle. The percentage may include a range of 5 percent to 8 percent of the heart rate cycle, or may include a range of 5 percent to 8 percent of the heart rate cycle. Additional details regarding the detection of features of the end of cardiac diastole or the onset of cardiac systole are previously described in relation to Figure 18.

[0247] In block 1908, systole or diastole can be determined. Feature detection service 1412 can detect diastolic or systolic features. Feature detection service 1412 can use dicrotic notch features to identify the phase transition from diastole to systole. The end of cardiac diastole or the start of cardiac systole are other features that can be detected.

[0248] d. Additional valve conditions The cardiac valve evaluation system 1400 can determine additional valve conditions. Additional valve conditions may include, but are not limited to, transvenous functional diagnosis, indicators of severe valve stenosis, indicators of aortic regurgitation, and / or indicators of modified aortic regurgitation.

[0249] i. Indicators of the severity of valve stenosis Although the aortic valve is used to illustrate a specific embodiment, the techniques described herein can also be applied to other valves such as the mitral valve, pulmonary valve, or tricuspid valve. Figure 20 depicts the left ventricular pressure waveform (LVEP)2010 and the aortic pressure waveform (AOP)2011. In the example in Figure 20, aortic stenosis may be present. Aortic stenosis can obstruct blood from passing through the valve, which can cause a loss or decrease in pressure. Pressure loss can occur during cardiac contraction. In fact, pressure loss can occur during the period when blood is ejected from the left ventricle into the aorta (ejection period). The ejection period2012 is defined as the period defined by the point where the left ventricular pressure intersects with the aortic pressure.

[0250] In a normal, healthy subject, left ventricular pressure and aortic pressure should be equal during ejection time. However, in the case of aortic stenosis, left ventricular pressure may be higher than aortic pressure. Pressure loss can increase with the severity of aortic stenosis. Techniques for assessing the severity of aortic stenosis (AS) may include calculating the pressure gradient between LVP and AOP over the entire ejection time. Specifically, the severity of aortic stenosis (AS) can be assessed by the gradient between mean LVP and mean AOP over the ejection time, as shown by Region 2013. <lvsp> - <asp>) may be determined based on the following: <lvsp>This can be defined as the mean left ventricular systolic pressure during the ejection period. <asp>This can be the mean aortic systolic pressure during the ejection period. Improved techniques may include excluding the marginal portions of the ejection period and calculating the pressure gradient in the region where the instantaneous pressure gradient is more constant. This can be done by calculating the mean pressure gradient for the middle 50% of the ejection period, thus excluding 25% of the period at both margins. Other percentages of the middle portion are also possible, such as 30%, 40%, 60%, 70%, or 80%.

[0251] However, this technique may be sensitive to pressure amplitude. Other techniques consist of normalizing the aortic stenosis index (AS) by dividing the gradient of the mean pressure by the mean LVEP, as indicated by the following formula.

[0252]

number

[0253] <lvsp>This can be defined as the mean left ventricular systolic pressure during the ejection period. <asp>can be the mean aortic systolic pressure during the ejection period.

[0254] At rest, it can be assumed that the total amount of blood supply is appropriate, that is, the aortic pressure during the ejection period enables appropriate overall perfusion. In the absence of aortic stenosis, it may be reasonable to assume that the left ventricular pressure during the ejection period is equal to the aortic pressure in the presence of aortic stenosis. The total vascular resistance, whether aortic stenosis is present or not, may not change.

[0255]

Number

[0256] The value of corresponds to the loss of available perfusion caused by the presence of aortic stenosis. In a normal healthy subject without aortic stenosis, <000​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0264] can represent the percentage of available perfusion of a stenotic valve relative to a normal valve.

[0265]

Number

[0266] and

[0267]

Number

[0268] can be calculated by taking the average pressure over the entire ejection period or by taking the pressure over a portion of the ejection period. Other metrics consist of taking the maximum instantaneous gradient between LVSP and ASP during the ejection period.

[0269] ii. Indicator of aortic regurgitation Regurgitation can occur when blood leaks back through the valve. Regurgitation can be caused by valve disease or, in the case of prosthetic replacement, by incomplete seating of the replacement valve relative to the native valve. The post-treatment outcome of patients following valve replacement can be adversely affected by valve regurgitation. Therefore, diagnosing post-TAVI valve regurgitation and the available pre-TAVI regurgitation for valve adjustment can be important.

[0270] Figure 21 shows the pressure waveform of a normal healthy subject. Figure 22 shows a similar pressure waveform with aortic valve regurgitation. Blood flowing through the valve and flowing back in the left ventricle can increase the left ventricular diastolic pressure. This can also decrease the aortic diastolic pressure as a result of the volume of blood lost through the closed aortic valve. The systolic pressure can increase to compensate for the loss of available blood perfusion.

[0271] The aortic regurgitation index (AR) can be calculated by determining the gradient 2220 between the ventricular pressure at the end of diastolic pressure (LVEDP) and the aortic pressure at the end of diastolic pressure (AEDP), normalized by the aortic systolic pressure (ASP), as shown by the following formula:

[0272]

number

[0273] Another metric that can provide better stability and reproducibility consists of calculating the gradient between mean left ventricular diastolic pressure (LVDP) and mean aortic diastolic pressure (ADP), divided by aortic systolic pressure (ASP). Another metric consists of calculating the same gradient over a portion of diastole, for example, over a period when left ventricular pressure is below a certain value, more specifically, over a period when LVDP is in a region where it is relatively flat. A predetermined portion of cardiac diastole may be used to calculate the regurgitation metric, for example, by taking 75% of the left portion of cardiac diastole.

[0274] iii. Modified indicators of aortic regurgitation Atherosclerosis, which can be common in patients undergoing valve replacement, affects pressure waveforms in a similar manner to aortic regurgitation. In these cases, the above indicators of aortic regurgitation may lead to a false determination of positive regurgitation, which may further lead to unnecessary valve adjustments. More specifically, atherosclerosis has the effect of increasing systolic pressure. In Figure 23, this pressure increase may be caused by reflected pressure waves from a hardened vascular system, which occur more readily than in a normal vascular system. In a normal vascular system, the reflected waves occur later during cardiac diastole, and therefore an increase in diastolic pressure can occur earlier in the diastolic pressure.

[0275] The pressure during cardiac diastole can be withstood by the compliance of the vascular system. The distensibility of the arteries, primarily the aorta, maintains pressure within the vascular system by retracting to return to a voluntary state. Hardened arteries do not have the same degree of compliance and therefore are unable to withstand the expanded pressure during cardiac diastole. Because the diastolic pressure drops more rapidly, the aortic pressure at the end of diastole (AEDP) also drops more rapidly, and therefore aortic regurgitation is reduced.

[0276] Diastolic pressure can be represented by a two-component model that includes vascular compliance (C) and overall vascular resistance (R). Diastolic pressure relaxes as expressed by the following diastolic formula.

[0277]

number

[0278] If compliance is known, the formula allows for the calculation of total vascular resistance (R). The pressure at the end of diastole in the aorta can be recalculated using the general, normal compliance along with the previously calculated total vascular resistance.

[0279] Compliance can be defined as the gain in arterial volume caused by a given pressure change, as indicated by the following formula.

[0280]

number

[0281] ΔV is obtained by measuring the relative change in arterial diameter. ΔV can be more easily measured by measuring left ventricular output, which is obtained from the difference in left ventricular contour measurements by angiography between cardiac contraction and cardiac diastole. ΔP is the gradient of the aorta from contraction to diastole.

[0282] Atherosclerosis can be well correlated with increased pressure (AP)2330, or conversely, compliance can be well correlated with the reciprocal of increased pressure. It is preferable to correct aortic regurgitation using increased pressure because it may be easier to implement in clinical practice. Increased pressure is accompanied by a visible change in the elevated portion of cardiac contraction2331, allowing for estimation of increased pressure. Another method is to inject nitroglycerin into the patient, as nitroglycerin relaxes the arterial system and reduces increased pressure. The change in aortic systolic pressure caused by nitroglycerin can give an increased pressure. Compliance can be estimated in the form of the following compliance formula, or in any relationship of f(AP) adjusting the assumed general normal compliance Cn using increased pressure. C=f(AP)=C n -k·AP

[0283] R can be calculated by applying C in the above formula to the diastolic formula using diastolic aortic pressure measurement. The corrected aortic diastolic pressure (CADP) is calculated by using the calculated R and Cn in the compliance formula. The corrected aortic regurgitation is calculated by replacing the aortic diastolic pressure (ADP) with the corrected aortic diastolic pressure (CADP), as shown in the following formula.

[0284]

number

[0285] Another method involves replacing the measured aortic systolic pressure with the corrected aortic systolic pressure, that is, removing the contribution of increased pressure from the ASP. The corrected aortic regurgitation can be calculated using the mean diastolic pressure calculation as described above, rather than using only the pressure value at the end of diastole.

[0286] The elevated diastolic pressure in the left ventricle caused by abnormal venous pressure can also lead to an inaccurate metric of aortic regurgitation. Another improved method involves subtracting the contribution of venous or atrial pressure from the diastolic pressure component of the left ventricle, as shown in the following formula.

[0287]

number

[0288] e. Additional pressure sensor calibration As described herein, a first sensor can be calibrated relative to a second sensor to determine a more accurate pressure measurement, which may also be referred to as equivalence. For example, a pressure guide wire may be at or near the location of a valve, along with other pressure devices. Other pressure devices may be a catheter, pigtail, or other device having a lumen used to deliver the valve and connected to a pressure transducer. The pressure device may be another pressure guide wire, or a catheter with a pressure sensor at its tip. Additional pressure devices may include piezoelectric sensors and / or optical sensors. Examples of pressure devices that can be equivalently selected may include, but are not limited to, pressure guide wires, catheters, pigtails, tip pressure sensors, piezoelectric sensors, and / or optical sensors. Thus, examples of combinations of pressure devices that can be equivalently selected may include two pigtails, two piezoelectric sensors, two optical sensors, and / or any other combination of pressure devices. However, unlike some of the calibration techniques described herein, in which the pressure instruments are positioned in the same cardiovascular region for calibration purposes, other calibration techniques described herein may be performed while the pressure instruments are positioned in different cardiovascular regions, such as a first instrument positioned in the left ventricle and a second instrument positioned in the aorta. As described herein, calibration of pressure instruments while the instruments are positioned in different cardiovascular regions of the heart may be achieved by detecting one or more features from the pressure waveform. Specifically, one or more features detected in the pressure waveform may be used to perform time adjustment and / or gain adjustment on the pressure waveform for the purpose of equivalence.

[0289] The systems and methods described herein for calibrating pressure sensors when pressure devices are located in different locations can improve the efficiency of pressure readings. For example, as previously stated, calibration can be performed when the pressure devices are located in the same cardiovascular region. However, ensuring that both pressure devices are located in the same cardiovascular region may add an additional step to cardiac procedures. The techniques described herein for calibration with time adjustment and / or gain adjustment from waveform characteristics can be performed advantageously when the pressure devices are located in different locations as required by cardiac procedures. Thus, the systems and methods described herein for calibration when pressure devices are located in different locations can improve the technology of pressure devices by providing more accurate pressure readings without adding an additional step to cardiac procedures.

[0290] The aortic pressure waveform can differ from the ventricular pressure waveform. For example, with respect to Figure 20 described earlier, the aortic pressure can begin to increase at the start of systole, as shown by the aortic pressure waveform 2011. Specifically, the aortic pressure can begin to increase when the aortic valve opens at the start of time period 2012, when the aortic valve is open. The aortic pressure waveform 2011 increases until it reaches at least a local maximum in time period 2012, which is the systolic pressure, and then decreases sharply until it reaches a dicrotic notch at the end of time period 2012. The dicrotic notch represents the moment when the aortic valve closes. These two moments when the aortic valve opens and closes can be useful for equivalence because they can represent the only point where ventricular pressure and aortic pressure can be equal. These two moments when the aortic valve opens and closes can generally correspond to the start and end of time period 2012, respectively. The left ventricular pressure waveform 2010 can cross with the aortic pressure waveform 2011 at the beginning and end of the time period 2012.

[0291] In Figure 24, pressure waveforms that may include a phase lag are depicted. Specifically, the left ventricular pressure waveform 2402 and the aortic pressure waveform 2404 are depicted. In contrast to the intersection of the left ventricular pressure waveform 2010 and the aortic pressure waveform 2011 in Figure 20, the left ventricular pressure waveform 2402 can intersect with the aortic pressure waveform 2404 in Figure 24 at different moments with respect to the characteristics of the aortic pressure waveform 2404. Specifically, in Figure 24, the left ventricular pressure waveform 2402 does not intersect with the aortic pressure waveform 2404 when the valve is open 2406 or at the dicrotic notch 2408. Calibration techniques described herein may be applied to the pressure waveforms in Figure 24. Specifically, time adjustment may be applied to the pressure waveforms in Figure 24.

[0292] Figure 25 depicts pressure waveforms that may contain gain errors. Specifically, left ventricular pressure waveform 2502 and aortic pressure waveform 2504 are depicted. In the pressure waveforms of Figure 25, there may be gain errors that could cause amplitude changes. For example, left ventricular pressure waveform 2502 may contain a gain error of approximately 1.3, which could cause expansion of the point where left ventricular pressure waveform 2502 intersects with aortic pressure waveform 2504. Specifically, the pressure value 2508 of left ventricular pressure waveform 2502 may be higher than the pressure value 2506 of aortic pressure waveform 2504 in the dicrotic notch feature of aortic pressure waveform 2504. In other examples, if the gain is less than 1, the intersecting points will approach each other (not shown). The calibration techniques described herein may be applied to pressure waveforms 2502 and 2504 in Figure 25. Specifically, gain adjustment may be applied to the pressure waveforms in Figure 25.

[0293] In Figure 26, pressure waveforms that may include phase lag and gain errors are depicted. Specifically, left ventricular pressure waveform 2602 and aortic pressure waveform 2604 are depicted. Calibration techniques described herein may be applied to pressure waveforms 2602 and 2604 in Figure 26. Specifically, time adjustment and / or gain adjustment may be applied to the pressure waveforms in Figure 26.

[0294] Figure 27 shows another example of calibration process 2700. While process 2700 is described in relation to a heart valve evaluation system such as system 200 in Figure 2A or system 1400 in Figure 14, any system configured to perform the process in any order is within the scope of this disclosure. Process 2700 may be performed by various components of the system in Figure 2A or system 1400 in Figure 14, as discussed herein, including the monitoring device 204. Depending on the embodiment, process 2700 may include fewer or additional blocks, and / or the blocks may be performed in a different order than those shown. Other embodiments of process 2700 may include fewer blocks than those shown, or the blocks may be performed in a different order than those shown.

[0295] In some embodiments, one set of pressure values ​​may come from a pressure sensor located in the left ventricle (such as a pressure fluid filling line), and another set of pressure values ​​may come from a different pressure sensor located in the aorta (such as a pressure guide wire). Furthermore, in some embodiments, the heart valve evaluation system 1400 may adjust the pressure values ​​for the left ventricle based on the output of the calibration process 2700. In some cases, the pressure fluid filling line has a relatively larger lag compared to the pressure guide wire due to the pressure propagation time in the fluid filling line. Therefore, adjusting the pressure of the left ventricle instead of the aortic pressure may be advantageous. As described herein, multiple options are possible. For example, additionally or alternatively, the heart valve evaluation system 1400 may adjust the pressure values ​​for the aorta based on the output of the calibration process 2700.

[0296] Starting in block 2702, pressure instruments may be set to zero. Specifically, the cardiac valve evaluation system 1400 may set one or more pressure instruments to zero. As used herein, “setting to zero” can be described as the process by which external pressures, such as atmospheric pressure, in the system 1400 may be neutralized. The system 1400 may set one or more pressure instruments to zero in order to eliminate other pressure signals other than the actual pressure from the patient. By setting them to zero, more accurate data can be obtained that forms the basis for treatment / action decisions.

[0297] In block 2704, pressure values ​​or signals may be received or determined. Specifically, the cardiac valve evaluation system 1400 can receive pressure signals from pressure sensors such as a pressure guide wire 208, a pressure-sensing access catheter 20, a pressure-sensing pigtail catheter 10, a tip pressure sensor, a piezoelectric sensor, and / or an optical sensor. From the received pressure signals, the cardiac valve evaluation system 1400 can determine a first set of pressure values ​​and a second set of pressure values. Each pressure value from the first set of pressure values ​​may correspond to a first signal received from a first pressure sensor measuring a first cardiovascular region. Each pressure value from the second set of pressure values ​​may correspond to a second signal received from a second pressure sensor measuring a second cardiovascular region different from the first cardiovascular region. For example, the first pressure sensor may be located in a first part of the heart, and the second pressure sensor may be located in a cardiovascular region adjacent to the first part of the heart. The heart valve evaluation system 1400 can determine first and second sets of pressure values ​​from first and second sensors, respectively. This block 2704 for receiving pressure values ​​or signals may be similar to block 1502 in Figure 15 for receiving pressure values ​​or signals.

[0298] In block 2706, feature detection may be performed. Feature detection service 1412 can perform feature detection. Examples of features that can be detected from a pressure waveform may include systole, diastole, dichroic notch, end of cardiac diastole, and / or start of cardiac systole. Feature detection service 1412 can identify features in the pressure waveforms of the examples in Figures 24-26. Specifically, feature detection service 1412 can determine the substantial start of systole in a set of pressure values. As another example, feature detection service 1412 can determine a dichroic notch feature in a set of pressure values. Additional details regarding feature detection are described in more detail earlier in relation to process 1900 in Figure 19. This block 2706 for performing feature detection may be similar to block 1508 in Figure 15 for performing feature detection.

[0299] In some embodiments, the feature detection service 1412 can perform feature detection by applying one or more thresholds. In some pressure waveforms, the point of crossover that opens the valve may not be complete at the start of cardiac contraction, but slightly after or before. For example, the pressure required to open a severely calcified valve leaflet may delay pressure transmission in the aorta, resulting in a flatter aortic pressure curve, which may alter the point of crossover. For example, the feature detection service 1412 may identify the substantial start of systole within a set of pressure values, within a range of percentages of the heart cycle before or after the end of diastole. As another example, the feature detection service 1412 may identify a timestamp corresponding to a dicrotic notch feature, the timestamp may be within a range of percentages of the heart cycle before or after the dicrotic notch in a set of pressure values. Example threshold percentages may be between approximately 0 percent and 1 percent of the heart cycle, between approximately 0 percent and 2 percent, between approximately 0 percent and 5 percent, and between approximately 0 percent and 10 percent.

[0300] In block 2708, time adjustments can be calculated. Specifically, calibration service 1408 can calculate time adjustments. Calibration service 1408 can calculate time adjustments to cross a set of pressure values ​​with a base set of pressure values ​​at the substantial start of systole in the base set of pressure values. For example, in the pressure waveform situation of Figure 24, calibration service 1408 can calculate time adjustments to cross the left ventricular pressure waveform 2402 with the aortic pressure waveform 2404 at the substantial start of systole / when the valve opens 2406. The time adjustments in the example may be time values ​​in units of time such as milliseconds or seconds. In block 2710, time adjustments can be applied. Specifically, calibration service 1408 can apply time adjustments to a set of pressure values ​​so that the values ​​from the set of pressure values ​​correspond to the values ​​at the substantial start of systole in the base set of pressure values.

[0301] In block 2712, gain adjustments can be calculated. Specifically, calibration service 1408 can calculate gain adjustments. Calibration service 1408 can measure the pressure difference at the location of the dicrotic notch and calculate the required gain correction. Specifically, calibration service 1408 can use the detected dicrotic notch feature in a base set of pressure values. Calibration service 1408 can identify the timestamp corresponding to the dicrotic notch feature and determine a first value in the timestamp from the base set of pressure values. Calibration service 1408 can further determine a second value in the timestamp from another set of pressure values. The first value corresponds to V1, the second value corresponds to V2, the gain adjustment may include g, and an example formula for calculating the gain adjustment may substantially include the following relational determinations.

[0302]

number

[0303] For example, in the pressure waveform situation shown in Figure 25, the calibration service 1408 can calculate the gain adjustment from the pressure value 2506 of the aortic pressure waveform 2504 divided by the pressure value 2508 of the left ventricular pressure waveform 2502 (i.e., Gain correction =Ao Dicrotic / Lv Dicrotic ).

[0304] In block 2714, gain adjustment may be applied. Specifically, the calibration service 1408 may apply gain adjustment to a set of pressure values ​​to achieve gain correction. In some embodiments, the calibration service 1408 may multiply each value by the gain adjustment to form a set of pressure values ​​that vary the amplitude of the pressure value.

[0305] In block 2716, it can be determined whether the termination conditions for calibration process 2700 have been met. Specifically, calibration service 1408 can determine whether the termination conditions have been met. An example termination condition may include determining whether the point of intersection for a set of pressure values ​​is within the threshold of the underlying set of pressure values ​​for one or more detected features. For example, calibration service 1408 may determine that the intersection from the left ventricular pressure waveform is within the threshold from the substantial start of systole in the aortic pressure value. As another example, calibration service 1408 may determine that the intersection from the left ventricular pressure waveform is within the threshold from the dicrotic notch feature in the aortic pressure value. If the conditions are not met, the process can return to the previous blocks 2708, 2710, 2712, and 2714 to recalculate and apply calibration parameters such as time adjustment and / or gain adjustment. Thus, calibration service 1408 can operate in a loop until the termination conditions are met. For example, in some embodiments, the calibration service 1408 can operate in a loop until the crossover of the pressure waveforms coincides with the opening of the valve as indicated by the features in the pressure waveforms. If the termination condition is met, the process proceeds to block 2718.

[0306] In block 2718, the determined calibration parameters may be stored and / or used. Specifically, calibration service 1408 may store and / or use time adjustments and / or gain adjustments. For example, calibration service 1408 may apply time adjustments and / or gain adjustments to a set of pressure values ​​and / or signals received from the pressure instrument after calibration is complete.

[0307] Implementing Organization Figure 28 is a block diagram showing the components of an example of a heart valve evaluation system 1400. Although the heart valve evaluation system 1400 in Figure 28 is depicted as a single device, the heart valve evaluation system 1400 may be implemented in a server cluster, server farm, data center, mainframe, cloud computing environment, etc. The heart valve evaluation system 1400 may include any number of devices that operate as distributed computing resources providing services such as storage, computation, and network formation.

[0308] The heart valve evaluation system 1400 may comprise a hardware processing unit 2802, a data storage device 2804, a memory device 2806, a bus 2808, a display device 2812, and one or more input / output devices 2814. The processing unit 2802 may be implemented as a combination of arithmetic units, such as a combination of a digital signal processing unit and a microprocessor, multiple microprocessors, one or more microprocessors used in conjunction with a digital signal processing unit, or any other such configuration. The processing unit 2802 may be configured, among many others, to process data or to execute instructions to perform one or more functions. The data storage device 2804 may comprise a magnetic disk, optical disk, or flash device, etc., and may be provided to and coupled to the bus 2808 for storing information and instructions. The memory 2806 may comprise one or more memory devices for storing data, including, but not limited to, random access memory (RAM) and read-only memory (ROM). The heart valve evaluation system 1400 may be coupled via bus 2808 to a display device 2812, such as an LCD display device or touchscreen, for displaying information to a user, such as a patient. The heart valve evaluation system 1400 may be coupled via bus 2808 to one or more input / output devices 2814. The input devices 2814 may include, but are not limited to, a keyboard, mouse, digital pen, microphone, touchscreen, gesture recognition system, voice recognition system, imaging device (which may capture data and / or placement tracking of eyes, hands, head, or body), gamepad, accelerometer, or gyroscope.

[0309] The heart valve evaluation system 1400 may comprise one or more software engines (or services) for performing the processes and functions described herein. The software engines may include program instructions for performing the processes, as detailed herein (and shown in the flowcharts), for detecting input states such as pressure signals and generating output states such as heart valve states. The engines may be executed by one or more hardware processing units 2802. The program instructions may be stored in a data storage unit 2804 and / or loaded into memory 2806. The program instructions may be executed in C, C++, Java®, or any other suitable programming language. In some embodiments, some or all of the parts of the heart valve evaluation system 1400, including the engines, may be executed by hardware processing units of application-specific circuits such as ASICs and FPGAs. Some aspects of the functionality of the heart valve evaluation system 1400 may be performed remotely on a server (not shown) via a network. Furthermore, some aspects of the functionality of the heart valve evaluation system 1400 may be performed by one or more sensors or external devices.

[0310] The cardiac valve evaluation system 1400 can communicate with one or more sensor devices 2816 described herein, such as a pressure guide wire 208, a pressure-sensing access catheter 20, or a pressure-sensing pigtail catheter 10.

[0311] term As used herein, relative terms such as "proximal" and "distal" are defined from the perspective of the system user. Therefore, proximal refers to the direction toward the system user, and distal refers to the direction toward the system user.

[0312] As used herein, relative terms such as “upstream” and “downstream” are defined from the perspective of blood flow. Therefore, downstream refers to the direction toward the aorta relative to the left ventricle.

[0313] Conditional words such as "can," "may," "may," or "may" are generally intended to convey that certain features, elements, and / or steps are included in certain embodiments but not in others, unless otherwise explicitly stated or understood in the context in which they are used. Therefore, such conditional words are generally not intended to imply that those features, elements, and / or steps are required in any form for one or more embodiments.

[0314] Terms such as "equipped with," "contains," and "have" are synonyms and are used in an open-ended, inclusive manner, without excluding additional elements, features, actions, or behaviors. Similarly, the term "or" is used in its inclusive sense (not its exclusive sense), for example, when used to connect a list of elements, meaning one, some, or all of the elements in the list.

[0315] The terms “approximately,” “about,” “generally,” and “substantially,” as used herein, refer to an amount close to the stated amount that still performs the desired function or still achieves the desired result. For example, the terms “approximately,” “about,” “generally,” and “substantially” may refer to an amount that is less than 5% of the stated amount, as the context may indicate.

[0316] The scope disclosed herein includes any and all overlaps, partial scopes, and combinations thereof. Words such as “up to,” “at least,” “greater than,” “less than,” and “between” include the proposed number. Numbers preceded by terms such as “about” or “approximately” include the proposed number. For example, “about 4” includes “4.”

[0317] Any method disclosed herein does not need to be performed in the order suggested. The methods disclosed herein include specific actions taken by the implementer, but may also include, explicitly or implicitly, commands of any third party to perform those actions. For example, an action such as "moving the locking element distally" includes "commanding the movement of the locking element distally."

[0318] While specific embodiments and examples are described herein, it will be understood by those skilled in the art that many of the embodiments of the humeral assemblies illustrated and described herein can still be combined and / or modified in different ways to form further embodiments or acceptable examples. All such modifications and variations are intended to be included within the scope of this disclosure herein. A wide variety of designs and methods are possible. None of the features, structures or steps disclosed herein are essential or indispensable.

[0319] Some embodiments are described in relation to the accompanying drawings. However, it should be understood that the drawings are not drawn to a specific scale. Distances, angles, etc., are merely illustrative and do not necessarily have a precise relationship to the actual dimensions and arrangement of the illustrated apparatus. Components may be added, removed, and / or rearranged. Furthermore, any specific features, aspects, methods, properties, characteristics, qualities, attributes, elements, etc., disclosed herein relating to various embodiments may be used in all other embodiments described herein. It should also be recognized that any method described herein can be carried out using any apparatus suitable for performing the proposed steps.

[0320] For the purposes of this disclosure, specific aspects, advantages, and novel features are described herein. It will be understood that all such advantages, which are not necessarily required, can be achieved according to any particular embodiment. Accordingly, those skilled in the art will recognize, for example, that this disclosure can be embodied or performed in a manner that achieves one or more advantages as taught herein, without necessarily achieving other advantages as taught or proposed herein.

[0321] Furthermore, while exemplary embodiments are described herein, the scope of any and all embodiments having equivalent elements, variations, omissions, combinations (e.g., combinations of aspects across various embodiments), adaptations, and / or modifications will be understood by those skilled in the art in the art relating to this disclosure. Limitations in the claims are to be interpreted broadly on the basis of the words used in the claims and are not limited to the examples described herein or those described during the examination of this application, and such examples are to be interpreted non-exclusively. Furthermore, the actions of the disclosed processes and methods may be modified in any manner, including by rearranging the actions, inserting additional actions, and / or deleting actions. Thus, this specification and the examples are considered illustrative only, and the true scope and spirit are intended to be indicated by the full scope of the claims and their equivalents. [Explanation of Symbols]

[0322] 10 Pigtail Catheter 20 Access Catheters 30 Pressure guide wires 40 Pressure Sensors 200 diagnostic systems 202 Fiber Optic Interface Cable 204 Monitoring assembly, monitoring display device 207 Handle Location of pressure guide wire 208 in 206A, 206B, 206C, 206D 208 Pressure guide wire 210 Access Catheter 211 Access Catheter 212 Delivery System 213 Delivery System 214 Aortic Pigtail Catheter 250 Non-traumatic curved area 308 Pressure guide wire 310 Outer tube 312 Coil section 314 intervals, gaps 316 core wire 318 Pressure Sensor Assembly 320 Pressure Wire Lead 322 Pressure Sensor 324 Sensor housing 326 Reduced diameter portion 328 Proximal portion 408 Pressure guide wire 410 Outer tube 412 Coil section 416 core wire 418 Pressure Sensor Assembly 420 Pressure Wire Lead 422 Pressure Sensor 426 Reduced diameter portion 428 Unscaled diameter portion 430 Connector tube 432 Distal tip 434 Insulated part 436 Adhesive 438a Area 1 438b Second area 440 Aperture 508 Pressure-sensing guide wire 510 Outer tube 512a, 512b Coiled area, coil portion 516 core wire 518 Pressure Sensor Assembly 520 Pressure Wire Lead 522 Pressure Sensor 526 Reduced diameter portion 528 Proximal portion 530 Connector Tube 542 Pressure sensor housing 544 Aperture 608 Pressure-sensing guide wire 612a Coil section 616 core wire 626 Reduced diameter portion 632 Distal tip 708 Pressure-sensing guide wire 716 core wire 722 Pressure Sensor 730 Connector Tube 742 Sensor housing 746 Area with reduced diameter 754 Tapered section 808 Pressure-sensing guide wire 810 Outer tube 812a, 812b Coil section 816 core wire 820 Pressure Wire Lead 822 Pressure Sensor 826 Reduced diameter portion 830 Connector Tube 838a Area 1 838b Second area 842 Sensor housing 848 connector 852 Aperture 908 Pressure-sensing guide wire 910 Outer tube 912 Coil section 920 Pressure Wire Lead 922 Pressure Sensor 924 Sensor housing area 930 Connector Tube 932 Distal tip 934 Insulation part 948 Connector 956 Proximal end 1000, 1020, 1040, 1060, 1080 User Interface Graphs 1002, 1004, 1006, 1008 1010, 1012 Physiological parameters 1014 Record Options 1042a, 1042b, 1042c Gradient depiction 1044a, 1044b, 1044c Backflow depiction 1046 The first number 1048 The second number 1050 Electrocardiogram recording graph 1051 Pressure graph display unit 1052 Regeneration Control Unit 1054 Current playback position 1056 Gradient type selection section 1062a, 1062b, 1062c Gradient depiction 1064 numerical value 1082a, 1082b, 1082c Gradient depiction 1084 numerical values 1100, 1120, 1140 User Interface 1102, 1122, 1142 Gradient description 1104 Reverse flow depiction 1200 Configuration User Interface 1202 Statistical Measurement Period Selection Section 1400 Heart Valve Evaluation System 1402 Heart valve evaluation environment 1404 Input section 1406 Output section 1408 Calibration Service 1410 Waveform Adjustment Service 1412 Feature Detection Service 1414 Valve Status Determination Service 1416 Indicator calculation section 1418 Gradient Calculation Unit 1700 waveform analysis environment 1702 First set of pressure data points 1704 Second set of pressure data points 1800 waveform analysis environment 1801 Cardiac contraction 1802 Slope 1806 waveform 1803 Minimum or locally minimum pressure value 1804 horizontal line 1805 Intersection 1807 hours, end of cardiac dilation 2010 Left ventricular pressure waveform 2011 Aortic Pressure Waveform 2012 Dispatch period, time period 2013 area 2220 The gradient between ventricular pressure at the end of diastole and aortic force at the end of diastole. 2221 Slope between mean left ventricular diastolic pressure and mean aortic diastolic pressure 2222 Specific value 2330 Pressure increase 2331 Cardiac contraction 2402 Left ventricular pressure waveform 2404 Aortic pressure waveform 2406 When the valve opens 2408 Dichroic Notch 2502 Left ventricular pressure waveform 2504 Aortic pressure waveform 2506 Pressure values ​​of aortic pressure waveform 2508 Pressure values ​​of the left ventricular pressure waveform 2602 Left ventricular pressure waveform 2604 Aortic pressure waveform 2802 Hardware Processing Unit 2804 Data storage device 2806 Memory device 2808 Bus 2812 Display device 2814 Input / Output Devices Aorta L Longitudinal axis of pressure guide wire LA (Left Atrium) LV left ventricle M Mitral valve P cusp RA right atrium RV right ventricle VC Inferior vena cava, superior vena cava< / asp> < / lvsp> < / asp> < / lvsp> < / asp> < / lvsp>

Claims

1. A non-temporary computer storage medium configured to store at least computer executable instructions, One or more hardware processing devices communicating with the aforementioned non-temporary computer storage medium, wherein at least, Calibrating the second pressure sensor relative to the first pressure sensor while both the first and second pressure sensors are positioned in the heart, wherein the calibration of the second pressure sensor is Determining a first set of pressure values ​​from the first pressure sensor located in a first part of the heart, Determining a second set of pressure values ​​from the second pressure sensor located in the cardiovascular region adjacent to the first portion of the heart, To detect the value at the start of systole in the first plurality of pressure values, and Calculating time adjustments to the second set of pressure values ​​such that the second set of pressure values ​​intersects with the values ​​at the start of the systolic phase in the first set of pressure values, Calibrate the second pressure sensor, including To determine a third set of pressure values ​​from the first pressure sensor located in the first part of the heart, Determining a fourth plurality of pressure values ​​from the second pressure sensor located in the cardiovascular region adjacent to the first portion of the heart, wherein determining the fourth plurality of pressure values ​​is To determine a fourth set of pressure values, which includes applying the aforementioned time adjustment to a set of initial pressure values, To detect the first characteristic at the third set of pressure values, To detect the second characteristic at the fourth set of pressure values, The condition of the heart valves is determined based at least partially on the first and second features, To display the aforementioned heart valve status on the user interface, One or more hardware processing units configured to execute the aforementioned computer executable instructions A system equipped with these features.

2. Calibrating the second pressure sensor with respect to the first pressure sensor is, To detect dicrotic notch features at the aforementioned first set of pressure values, Identifying the timestamp corresponding to the aforementioned dichroic notch feature, From the aforementioned first plurality of pressure values, determine the first value in the timestamp, From the fourth set of pressure values ​​and the time adjustment, determine the second value in the timestamp, and The method further includes calculating the gain adjustment based at least partially on the first and second values, Determining the fourth set of pressure values ​​means The system according to claim 1, further comprising applying the gain adjustment to a set of pressure values.

3. Identifying the timestamp corresponding to the aforementioned dicrotic notch feature is, The system according to claim 2, further comprising identifying the timestamp within a range of percentages of heart cycles before or after the dicrotic notch feature in the first plurality of pressure values.

4. The first value is V １ Corresponding to the above, the second value is V ２ Corresponding to this, the gain adjustment includes g, and calculating the gain adjustment is related to determining the relationship. [Math 1] The system according to claim 2, further comprising:

5. The one or more hardware processing devices are The system according to claim 1, further configured to identify the start of systole within a range of percentages of the heart cycle before or after the end of diastole in the first plurality of pressure values.

6. The first feature is the system according to claim 1, wherein at least one of a first systolic period or a first diastolic period is provided for the third plurality of pressure values.

7. Detecting at least one of the first systolic phase or the first diastolic phase is: The method involves detecting a first dicrotic notch feature at the third set of pressure values, Calculating multiple second derivative values ​​from the first multiple pressure values, and Identifying the zero-crossing point corresponding to the first dichroic notch feature based at least partially on the plurality of second derivative values. To detect a first dichroic notch feature, Depending on the first dichroic notch feature, at least one of the first systole or the first diastolic phase is identified. The system according to claim 6, further comprising:

8. A non-temporary computer storage medium configured to store at least computer executable instructions, One or more hardware processing devices communicating with the aforementioned non-temporary computer storage medium, wherein at least, Calibrating the second pressure sensor relative to the first pressure sensor while both the first and second pressure sensors are positioned in the heart, wherein the calibration of the second pressure sensor is Determining a first set of pressure values ​​from the first pressure sensor located in a first part of the heart, Determining a second set of pressure values ​​from the second pressure sensor located in the cardiovascular region adjacent to the first portion of the heart, To identify the value at the start of systole in the first plurality of pressure values, and The time adjustment to the second set of pressure values ​​is calculated so that the second set of pressure values ​​intersects with the value at the start of the systolic phase in the first set of pressure values. Calibrate the second pressure sensor, including To determine a third set of pressure values ​​from the first pressure sensor located in the first part of the heart, Determining a fourth plurality of pressure values ​​from the second pressure sensor located in the cardiovascular region adjacent to the first portion of the heart, wherein determining the fourth plurality of pressure values ​​is To determine a fourth set of pressure values, which includes applying the aforementioned time adjustment to a set of initial pressure values, To present a first user interface including a first graph based at least partially on the third plurality of pressure values ​​and a second graph based at least partially on the fourth plurality of pressure values, One or more hardware processing units configured to execute the aforementioned computer executable instructions A system equipped with these features.

9. Calibrating the second pressure sensor with respect to the first pressure sensor is, To detect dicrotic notch features at the aforementioned first set of pressure values, Identifying the timestamp corresponding to the aforementioned dichroic notch feature, From the aforementioned first plurality of pressure values, determine the first value in the timestamp, From the fourth set of pressure values ​​and the time adjustment, determine the second value in the timestamp, and The method further includes calculating the gain adjustment based at least partially on the first and second values, Determining the fourth set of pressure values ​​means The system according to claim 8, further comprising applying the gain adjustment to a set of pressure values.

10. Identifying the timestamp corresponding to the aforementioned dicrotic notch feature is, The system according to claim 9, further comprising specifying the timestamp within a range of percentages of heart cycles before or after the dicrotic notch feature in the first plurality of pressure values.

11. The first value is V １ Corresponding to the above, the second value is V ２ Corresponding to this, the gain adjustment includes g, and calculating the gain adjustment is related to determining the relationship. [Math 2] The system according to claim 9, further comprising as follows:

12. The one or more hardware processing devices are The system according to claim 8, further configured to identify the start of systole within a range of percentages of the heart cycle before or after the end of diastole in the first plurality of pressure values.

13. The system according to claim 8, wherein the first user interface comprises a first gradient drawing that visually presents a first gradient measurement between a first peak in the first graph and a second peak in the second graph.

14. The one or more hardware processing devices are To receive user selection for a second gradient type via the first user interface, and It is further configured to present a second user interface for a second gradient type instead of the first user interface, The second user interface described above is: The first graph and the second graph, and, A second gradient diagram visually presents the region between the first graph and the second graph, wherein the region indicates the pressure difference between the first part of the heart and the second part of the heart, and the second gradient of the valve. The system according to claim 13, comprising:

15. The first user interface further comprises a first numerical value for the first gradient drawing, The one or more hardware processing devices are To receive user heart rate selection, and, The system according to claim 13, further configured to calculate the first value based at least in part on the user heart rate selection.

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