Presentation of intracardiac electrocardiogram

Abstract

To provide a medical system.SOLUTION: A medical system 20 includes: a catheter 40 including catheter electrodes to contact tissue at respective locations within a chamber of a heart 26; a display 27; and processing circuitry 41 to receive signals from the catheter 40 and, in response to the signals, sample respective voltage values of the signals at respective timing values, and render to the display respective intracardiac electrograms (IEGM) presentation strips representing electrical activity in the tissue that is sensed by the catheter electrodes at the respective locations, each of the IEGM presentation strips including a linear array of respective shapes associated with, and arranged in a temporal order of, respective ones of the timing values, fillers of the respective shapes being formatted responsively to respective ones of the sampled voltage values of respective ones of the signals sampled at respective ones of the timing values.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to medical systems, particularly but not exclusively to catheter-based systems. [Background technology]

[0002] A wide range of medical procedures involve the placement of probes, such as catheters, within a patient's body. To track such probes, position sensing systems have been developed. Magnetic position sensing is one method known in the art. In magnetic position sensing, magnetic field generators are typically placed at known locations outside the patient's body. A magnetic field sensor in the distal end of the probe generates electrical signals in response to these magnetic fields, and the signals are processed to determine the position coordinates of the distal end of the probe. These methods and systems are described in U.S. Patent Nos. 5,391,199, 6,690,963, 6,484,118, 6,239,724, 6,618,612 and 6,332,089, WO 1996 / 005768, and U.S. Patent Application Publication Nos. 2002 / 006455, 2003 / 0120150 and 2004 / 0068178. Position may be tracked using an impedance-based system or a current-based system.

[0003] One medical procedure in which these types of probes or catheters have proven extremely useful is in the treatment of cardiac arrhythmias. Cardiac arrhythmias, and atrial fibrillation in particular, remain a common and dangerous medical condition, especially in the elderly population.

[0004] The diagnosis and treatment of cardiac arrhythmias involves mapping the electrical properties of cardiac tissue, particularly the endocardium and cardiac volume, and selectively ablating cardiac tissue by application of energy. Such ablation can stop or modify the propagation of undesired electrical signals from one part of the heart to another. Ablation techniques destroy undesired electrical pathways by creating non-conductive lesions. Various modes of energy delivery have been previously disclosed for creating lesions, including the use of microwave, laser, and more generally radio frequency energy to create conduction blockages along cardiac tissue walls. In a two-step mapping-then-ablation procedure, a catheter equipped with one or more electrical sensors is typically advanced into the heart to sense and measure electrical activity at each point in the heart by acquiring data at multiple points. These data are then used to select a target area in the heart where the ablation should be performed.

[0005] Electrode catheters have been commonly used in medical practice for many years. Electrode catheters are used to stimulate and map electrical activity in the heart and to ablate sites of abnormal electrical activity. In use, the electrode catheter is inserted into a major vein or an artery, such as the femoral artery, and then guided into the chamber of the heart to be targeted. A typical ablation procedure involves inserting a catheter with one or more electrodes at its distal end into a heart chamber. A reference electrode may be provided by a second catheter, typically taped to the patient's skin or placed in or near the heart. When a radio frequency (RF) current is applied to the tip electrode of the ablation catheter, the current flows in the medium surrounding the tip electrode, i.e., blood and tissue, toward the reference electrode. The distribution of the current depends on the amount of electrode surface in contact with the tissue compared to blood, which is more conductive than tissue. Heating of the tissue occurs due to the electrical resistance of the tissue. If the tissue is heated sufficiently, the cells of the cardiac tissue are destroyed, forming a non-conductive lesion in the cardiac tissue. Summary of the Invention [Means for solving the problem]

[0006] According to one embodiment of the present disclosure, there is provided a medical system comprising: a catheter configured to be inserted into a heart chamber of a living body and having catheter electrodes configured to contact tissue at respective locations within the chamber of the heart; a display; and a processing circuit configured to receive signals from the catheter and, in response to the signals, sample respective voltage values ​​of the signals at respective timing values; and render on the display respective intracardiac electrogram (IEGM) presentation strips representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations, each of the IEGM presentation strips including a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in temporal order of the respective one of the timing values, with filler of the respective shapes formatted according to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values.

[0007] Further, according to an embodiment of the present disclosure, the processing circuitry is configured to render the respective IEGM presentation strips on a display, with the filling of the respective shapes being colored at least in part in response to a respective one of the sampled voltage values ​​of a respective one of the sampled signals at a respective one of the timing values.

[0008] Still further, in accordance with an embodiment of the present disclosure, the processing circuitry is configured to render each IEGM presentation strip on a display, with a transparency of the filling of each shape being adjusted in response to a respective one of the sampled voltage values ​​of a respective one of the sampled signals at a respective one of the timing values.

[0009] Additionally, according to an embodiment of the present disclosure, the processing circuitry is configured to derive a value for an attribute of a respective one of the signals in response to a respective one of the sampled voltage values ​​and a respective one of the timing values, and to render a respective IEGM presentation strip on the display, the filling of the respective shape being formatted according to a first formatting in response to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values, and the filling of the respective one of the shapes also being formatted according to a second formatting in response to the derived value.

[0010] Further, according to an embodiment of the present disclosure, the attribute is a rate of change of the sampled voltage values.

[0011] Further, according to an embodiment of the present disclosure, the attribute is a distinction between each of the signals.

[0012] Still further, in accordance with an embodiment of the present disclosure, the first formatting includes a color formatting and the second formatting includes a transparency formatting.

[0013] Additionally, according to an embodiment of the present disclosure, the first formatting includes a transparency formatting and the second formatting includes a color formatting.

[0014] Further, according to an embodiment of the present disclosure, the processing circuitry is configured to render on the display each IEGM presentation strip having at least one additional marker selected from any one of an alphanumeric symbol, another symbol, a line, a dot, a time annotation, a maximum value of the current data, and a pacing spike.

[0015] According to another embodiment of the present disclosure, there is provided a medical method including receiving a signal from a catheter configured to be inserted into a chamber of a heart of a living subject and having catheter electrodes configured to contact tissue at respective locations within the chamber of the heart; in response to the signal, sampling respective voltage values ​​of the signal at respective timing values; and rendering on a display respective intracardiac electrogram (IEGM) presentation strips representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations, each of the IEGM presentation strips including a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in temporal order of the respective one of the timing values, the filling of the respective shapes being formatted according to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values.

[0016] Further, according to an embodiment of the present disclosure, the rendering includes rendering the respective IEGM presentation strips on a display, with the filling of the respective shapes being colored at least in part in response to a respective one of the sampled voltage values ​​of a respective one of the sampled signals at a respective one of the timing values.

[0017] Still further, in accordance with an embodiment of the present disclosure, the rendering includes rendering the respective IEGM presentation strips on a display, with a transparency of the filling of the respective shapes being adjusted in response to a respective one of the sampled voltage values ​​of the respective one of the sampled signals at the respective one of the timing values.

[0018] Additionally, according to an embodiment of the present disclosure, the method includes deriving a value for an attribute of a respective one of the signals in response to a respective one of the sampled voltage values ​​and a respective one of the timing values, and the rendering includes rendering a respective IEGM presentation strip on a display, the filling of the respective one of the shapes being formatted according to a first formatting in response to the respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values, and the filling of the respective one of the shapes also being formatted according to a second formatting in response to the derived value.

[0019] Further, according to an embodiment of the present disclosure, the attribute is a rate of change of the sampled voltage values.

[0020] Further, according to an embodiment of the present disclosure, the attribute is a distinction between each of the signals.

[0021] Still further, in accordance with an embodiment of the present disclosure, the first formatting includes a color formatting and the second formatting includes a transparency formatting.

[0022] Additionally, according to an embodiment of the present disclosure, the first formatting includes a transparency formatting and the second formatting includes a color formatting.

[0023] Further, according to an embodiment of the present disclosure, the rendering includes rendering on the display each IEGM presentation strip having at least one additional marker selected from any one of an alphanumeric symbol, another symbol, a line, a dot, a time annotation, a maximum value of the current data, and a pacing spike.

[0024] According to yet another embodiment of the present disclosure, there is provided a software product including a non-transitory computer readable medium having program instructions stored thereon that, when read by a central processing unit (CPU), cause the CPU to: receive signals from a catheter configured to be inserted into a chamber of a heart of a living subject and having catheter electrodes configured to contact tissue at respective locations within the chamber of the heart; in response to the signals, sample respective voltage values ​​of the signals at respective timing values; and render on a display respective intracardiac electrogram (IEGM) presentation strips representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations, wherein each of the IEGM presentation strips includes a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in a temporal order of the respective one of the timing values, the filling of the respective shapes being formatted according to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values. [Brief description of the drawings]

[0025] The present invention will be understood from the following detailed description taken in conjunction with the accompanying drawings. [Figure 1] 1 is a schematic diagram of a medical treatment system constructed and operative in accordance with an embodiment of the present invention; [Diagram 2] FIG. 2 is a schematic diagram of a catheter for use in the system of FIG. 1. [Diagram 3] 2 is a schematic diagram of an IEGM trace and an IEGM presentation strip generated by the system of FIG. 1. [Figure 4] FIG. 1 is a schematic diagram of multiple IEGM presentation strips. [Diagram 5] 2 is a flow chart including steps in a method of operation of the system of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Overview As previously mentioned, in a two-step mapping-then-ablation procedure, a catheter with one or more electrodes is typically advanced into the heart to sense and measure electrical activity at each point within the heart by acquiring data at multiple points, which are then used to select a target region where ablation will be performed.

[0027] In particular, the electrical activity is usually displayed as an intracardiac electrogram (IEGM) trace that is analyzed by a physician to find the cause of the arrhythmia. Catheter electrodes that are not in contact with tissue within the heart typically measure some electrical signal and far-field signals from the cardiac tissue. When the catheter electrodes are in contact with the cardiac tissue, the voltage value of the signal is mainly based on the electrical conductivity of the tissue and the far-field is small. Therefore, physicians typically focus on analyzing the IEGM traces of electrodes in contact with the tissue.

[0028] For focal catheters with one or more electrodes, typically one IEGM trace is displayed for analysis by the physician. The physician can quickly determine whether the catheter electrode supplying the signal is in contact with tissue based on the signal morphology. However, multi-electrode catheters that simultaneously capture electrical activity from various tissue locations may simultaneously display data from multiple IEGM traces on a single display. In some cases, the number of IEGM traces may be so large that the physician cannot easily determine which IEGM traces are supplied by electrodes in contact with tissue and which are not.

[0029] One example of a multi-electrode catheter is the Octaray® catheter, which includes 48 or more electrodes, manufactured by Biosense Webster Inc., Irvine, Calif. The Octaray includes eight deflectable arms located at the distal end of the shaft, each of which includes six electrodes. Some catheters may include many more electrodes, such as, but not limited to, 120 electrodes.

[0030] In addition to the need to determine electrode contact during mapping as described above, effective ablation generally requires sufficient contact between the ablation electrode and the tissue, so the physician performing the ablation procedure monitors the electrode-tissue contact. When the number of electrodes is small, contact monitoring can be done by a numerical or graphical display of the degree of contact, such as the impedance observed at the electrode or the force applied to the electrode. However, as the number of active electrodes used in an ablation procedure increases, it becomes increasingly difficult for the physician to monitor any parameter of each individual electrode. In the case of electrode contact, this problem is exacerbated by the fact that in most cases the parameter that measures contact also changes as the contact changes.

[0031] An embodiment of the present invention solves the above problem during a medical procedure, such as a mapping or ablation procedure, by presenting a physician with a multi-channel, color-formatted IEGM presentation strip instead of showing an IEGM trace (a graph of voltage values ​​versus time). Each IEGM presentation strip represents a sampling of IEGM voltage values ​​of a signal (as detected by a respective catheter electrode) using colored shapes (e.g., rectangular, elliptical, oval, or any suitable shape) arranged in a linear array within the strip. The shapes are colored according to the sampled voltage values ​​and are arranged within the presentation strip according to the temporal order of the respective timing values ​​associated with the sampled voltage values ​​separated into the colored shapes. For example, each successive shape within the strip may correspond to the next timing value at which a sample was taken, with each shape being colored according to the sampled voltage value sampled at the timing value associated with that shape.

[0032] In this manner, the color coding of the linear array within the presentation strip represents the voltage value of the signal detected by each catheter electrode.

[0033] The presentation strips may be shown one above the other on the display, thereby allowing presentation of many IEGM presentation strips associated with multiple catheter electrodes to be presented on a single screen. Salient and other features of cardiac electrical activity, such as maximum and minimum voltage values, the spacing between peaks, and the rate of change of voltage values, may be gleaned from the strips. For example, the rate of change of voltage is indicated by the width of a color band within the strip. For example, a color change across a single shape represents a faster rate of change than a color change across several adjacent shapes.

[0034] In some embodiments, the shapes may be formatted using alternative formatting methods, for example using different transparency levels for the filling of the shape.

[0035] Additionally or alternatively, the shape of the IEGM presentation strip may be formatted to show another attribute of the signals, such as the rate of change of the respective signal, or a resolution of the respective signal. When different attributes of the signals are shown on a single IEGM presentation strip, one attribute may be represented using one formatting type (e.g., using a different coloring) and another attribute may be represented using a different formatting type (e.g., using a different transparency level).

[0036] In some embodiments, an IEGM waveform may optionally be displayed in addition to the IEGM presentation strip.

[0037] Some embodiments include a medical system including a catheter inserted into a chamber of a heart of a living subject, the catheter including electrodes in contact with tissue at respective locations within the chamber of the heart, and optionally processing circuitry for receiving a signal from the catheter and responsive to the signal for sampling respective voltage values ​​of the signal at respective timing values.

[0038] The processing circuitry optionally derives a value for an attribute of a respective one of the signals in response to the respective one of the sampled voltage values ​​and the respective one of the timing values, The attribute may be a rate of change of the sampled voltage value or a fraction of the respective one of the signals.

[0039] The processing circuitry is responsive to the signals to render on the display respective intracardiac electrogram (IEGM) presentation strips representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations. Each IEGM presentation strip includes a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in a temporal sequence of the respective one of the timing values. The filling of the respective shapes is formatted according to a respective one of the sampled voltage values ​​of a respective one of the signals sampled at the respective one of the timing values. In some embodiments, the filling is formatted based on the sampled voltage values ​​or based on the sampled voltage values ​​and another attribute based on the timing values ​​(e.g., rate of change or fraction of the voltage values). Thus, the formatting of the IEGM presentation strips may represent sampled amplitudes, rate of change, and / or fraction of the sampled voltage values.

[0040] In some embodiments, the processing circuitry renders on the display a respective IEGM presentation strip in which the filling of the respective shapes is at least partially colored in response to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values. In other embodiments, the processing circuitry renders on the display a respective IEGM presentation strip in which the transparency of the filling of the respective shapes is adjusted in response to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values.

[0041] In some embodiments, the processing circuitry renders the respective IEGM presentation strips on a display, where the filling of the respective shape is formatted according to a first formatting in response to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values, and the filling of the respective one of the shapes is also formatted according to a second formatting in response to a derived value (e.g., representing another attribute of the signal, such as a rate of change or fraction of the voltage value). Thus, at least a portion of the shapes may be formatted in both a first formatting and a second formatting. For example, at least a portion of the shapes may be formatted in both color and transparency. The first formatting and the second formatting may be selected from any suitable formatting scheme, such as, for example, but not limited to, a color formatting or a transparency formatting. In some embodiments, the first formatting includes a color formatting and the second formatting includes a transparency formatting. In other embodiments, the first formatting includes a transparency formatting and the second formatting includes a color formatting.

[0042] In some embodiments, the processing circuitry renders on the display each IEGM presentation strip having at least one additional marker selected from, by way of example only, any one of an alphanumeric symbol, another symbol, a line, a dot, a time annotation, a maximum value of the current data, and / or a pacing spike.

[0043] System Description Reference is now made to Figure 1, which is a schematic diagram of a medical procedure system 20 constructed and operative in accordance with an embodiment of the present invention. See also Figure 2, which is a schematic diagram of a catheter 40 for use in the system 20 of Figure 1.

[0044] The medical procedure system 20 is used to determine the position of a catheter 40, shown in inset 25 of Figure 1 and in more detail in Figure 2. The catheter 40 comprises a shaft 22 and a plurality of deflectable arms 54 (only some of which are labeled for simplicity) for insertion into a body portion of a living subject, such as a chamber of the heart 26. The deflectable arms 54 have respective proximal ends connected to a distal end of the shaft 22.

[0045] The catheter 40 includes a position sensor 53 disposed on the shaft 22 in a predetermined spatial relationship with respect to the proximal end of the deflectable arm 54. The position sensor 53 may include a magnetic sensor 50 and / or at least one shaft electrode 52. The magnetic sensor 50 may include at least one coil, such as, but not limited to, a biaxial or triaxial coil arrangement, for providing position and orientation position data, including rotation. The catheter 40 includes a plurality of electrodes 55 (only some of which are labeled in FIG. 2 for simplicity) disposed at different respective positions along each of the deflectable arms 54. Typically, the catheter 40 may be used to map electrical activity within a heart of a living subject using the electrodes 55, or to perform any other suitable function within a body part of a living subject. The electrodes 55 are configured to contact tissue of the body part at respective positions with the body part (e.g., within a chamber of the heart).

[0046] The medical procedure system 20 may determine the position and orientation of the shaft 22 of the catheter 40 based on signals provided by a magnetic sensor 50 attached to the shaft 22 and / or shaft electrodes 52 (proximal electrode 52a and distal electrode 52b) on either side of the magnetic sensor 50. The proximal electrode 52a, the distal electrode 52b, the magnetic sensor 50, and at least some of the electrodes 55 are connected to various driver circuits in the console 24 via the catheter connector 35 by wires extending through the shaft 22. In some embodiments, at least two electrodes 55 of each of the deflectable arms 54, the shaft electrodes 52, and the magnetic sensor 50 are connected to the driver circuits of the console 24 via the catheter connector 35. In some embodiments, the distal electrode 52b and / or the proximal electrode 52a may be omitted.

[0047] The diagram shown in Figure 2 has been selected solely for purposes of conceptual clarity. Other configurations of shaft electrode 52 and electrodes 55 are possible. Additional functionality may be included in position sensor 53. For clarity, elements not relevant to the disclosed embodiment of the invention, such as irrigation ports, have been omitted.

[0048] The physician 30 navigates the catheter 40 to a target location within a body part (e.g., the heart 26) of the patient 28 by manipulating the shaft 22 using a manipulator 32 near the proximal end of the catheter 40 and / or by deflection from the sheath 23. The catheter 40 is inserted through the sheath 23 with the deflectable arms 54 gathered together, and only after the catheter 40 is withdrawn from the sheath 23 are the deflectable arms 54 able to unfold and resume their intended functional shape. By housing the deflectable arms 54 together, the sheath 23 also serves to minimize vascular trauma during navigation to the target location.

[0049] The console 24 includes processing circuitry 41, typically a general-purpose computer, and suitable front-end and interface circuitry 44 for generating signals at and / or receiving signals from body surface electrodes 49 attached by wires that extend through cable 39 to the chest and back of the patient 28, or any other suitable skin surface.

[0050] The console 24 further comprises a magnetic sensing subsystem. The patient 28 is placed in a magnetic field generated by a pad including at least one magnetic field generator 42, which is driven by a unit 43 disposed in the console 24. The magnetic field generator 42 is configured to transmit an alternating magnetic field to a region in which a body part (e.g., the heart 26) is located. The magnetic field generated by the magnetic field generator 42 generates a directional signal in a magnetic sensor 50. The magnetic sensor 50 is configured to detect at least a portion of the transmitted alternating magnetic field and provide the directional signal as a corresponding electrical input to the processing circuit 41.

[0051] In some embodiments, processing circuitry 41 uses position signals received from shaft electrode 52, magnetic sensor 50, and electrode 55 to estimate the position of catheter 40 within an organ, such as within a heart chamber. In some embodiments, processing circuitry 41 correlates position signals received from electrodes 52 and 55 with previously acquired magnetic position calibration position signals to estimate the position of catheter 40 within a heart chamber. Position coordinates of shaft electrodes 52 and 55 may be determined by processing circuitry 41 based on impedance or current distribution percentages measured between electrodes 52, 55, and body surface electrodes 49, among other inputs. Console 24 drives display 27, which shows the distal end of catheter 40 within heart 26.

[0052] Position sensing methods using current distribution measurements and / or external magnetic fields are used in various medical applications, e.g., by Biosense Webster This technique has been implemented in a Carto® system manufactured by Intel Corporation of Irvine, California, and is described in detail in U.S. Pat. Nos. 5,391,199, 6,690,963, 6,484,118, 6,239,724, 6,618,612, 6,332,089, 7,756,576, 7,869,865, and 7,848,787, International Publication No. WO 96 / 05768, and U.S. Patent Application Publication Nos. 2002 / 0065455(A1), 2003 / 0120150(A1), and 2004 / 0068178(A1).

[0053] The Carto® 3 system applies an impedance-based position tracking method of active current position (ACL). In some embodiments, the processing circuitry 41 is configured to use the ACL method to create a mapping (e.g., a current-position matrix (CPM)) between a representation of the electrical impedance and a position in the magnetic coordinate frame of the field generator 42. The processing circuitry 41 estimates the positions of the shaft electrode 52 and the electrodes 55 by performing a lookup in the CPM.

[0054] The processing circuitry 41 is typically programmed with software to carry out the functions described herein. The software may be downloaded in electronic form to a computer, for example over a network, or alternatively or additionally may be provided and / or stored on a non-transitory, tangible medium, such as a magnetic, optical or electronic memory.

[0055] For purposes of brevity and clarity, Figure 1 shows only those elements relevant to the disclosed technique. System 20 typically includes additional modules and elements that are not directly relevant to the disclosed technology and therefore have been intentionally omitted from Figure 1 and the corresponding description.

[0056] The catheter 40 described above includes eight deflectable arms 54 with six electrodes per arm 54. For example, any suitable catheter may be used in place of catheter 40, such as, by way of example only, catheters with a varying number of flexible arms and / or multiple electrodes per arm, or catheters having different probe geometries, such as balloon catheters, basket catheters, or lasso catheters.

[0057] The medical procedure system 20 may also perform ablation of cardiac tissue using any suitable catheter, such as catheter 40 or a different catheter, and any suitable ablation method. The console 24 may include an RF signal generator 34 configured to generate RF power applied by one or more electrodes of a catheter connected to the console 24 and one or more body surface electrodes 49 to ablate the myocardium of the heart 26. The console 24 may include a pump (not shown) that pumps irrigation fluid into an irrigation channel to the distal end of the catheter performing the ablation. The catheter performing the ablation may further include a temperature sensor (not shown) that is used to measure the temperature of the myocardium during ablation and adjust the ablation power and / or the irrigation rate of pumping of the irrigation fluid according to the measured temperature.

[0058] Reference is now made to Figure 3, which is a schematic diagram of an IEGM waveform 60 and an IEGM presentation strip 62 generated by the system 20 of Figure 1. The IEGM waveform 60 illustrates the change in voltage value over time using a line graph for a signal received from one of the electrodes 55 (Figure 2) of the catheter 40.

[0059] To generate the IEGM presentation strip 62, the voltage values ​​of the received signal are sampled at suitable time intervals. The voltage values ​​at the sampled times may be positive or negative values. The time interval between samples may be any suitable value, for example, but not limited to, in the range of 1 to 50 milliseconds. The sampled voltage values ​​at each timing value are then converted to a color value. The color value may be derived based on looking up a color value in a table that maps a voltage value range to a color value. Alternatively, the color value may be calculated using a function that takes a voltage value as input and outputs a color value. The color value may be defined using a known color model, such as RGB, or based on a custom color model. Each shape 64 of the IEGM presentation strip 62 is assigned a respective timing value at which the signal was sampled. Each shape 64 is then colored according to a respective color value derived from the respective sampled voltage value sampled at each timing value.

[0060] For example, shapes 64-1 through 64-7 shown in inset 66 are assigned timing values ​​of 3900, 3910, 3920, 3930, 3940, 3950, and 3960 milliseconds, respectively. The voltages from the signal sampled at 3900, 3910, 3920, 3930, 3940, 3950, and 3960 milliseconds are equal to 1.2, 1.24, 1.3, 1.33, 1.31, 1.15, and 1.1, respectively. Color values ​​corresponding to red, red, dark red, dark red, dark red, orange, and orange are derived from the voltages 1.2, 1.24, 1.3, 1.33, 1.31, 1.15, and 1.1, respectively. Shapes 64-1 through 64-7 are then colored red, red, dark red, dark red, orange, and orange, respectively. Note that two or more different voltages may be mapped to the same color, for example voltages of 1.2 and 1.24 would both be mapped to the color red.

[0061] Shape 64 may be selected from any suitable shape, such as rectangular or oval. Shape 64 may have any suitable height, for example, from 1 to 100 mm, or even higher, depending on the size of display 27 (FIG. 1) and the number of IEGM presentation strips 62 displayed simultaneously. Shape 64 may have any suitable width, for example, from a single pixel to 5 mm, depending on the size of display 27 and the distance of the display from physician 30 (FIG. 1), as well as the timing interval between samples.

[0062] 3 is shown in greyscale due to patent drawing limitations, the IEGM presentation strip 62 may be represented on a display using color, where, by way of example, peaks are indicated using red (arrow 68) and dark red (arrow 69) and troughs are indicated using dark blue (arrow 70). Any suitable color coding may be used to represent voltage values ​​in any suitable color.

[0063] Salient and other features of cardiac electrical activity, such as maximum and minimum voltage values, the spacing between peaks, and the rate of change of voltage values, may be gleaned from the IEGM presentation strip 62. For example, the rate of change of voltage is indicated by the width of the color bands in the strip. For example, a color change across a single shape 64 represents a faster rate of change than a color change across several adjacent shapes 64.

[0064] In some embodiments, shapes 64 may be formatted using another formatting method (instead of using different colors), for example, using different transparency levels to fill shapes 64. The filling of shapes 64 may be a solid or patterned fill, with the transparency level adjusted according to the voltage value associated with the shape.

[0065] Reference is now made to Figure 4, which is a schematic diagram of multiple IEGM presenting strips 62. The IEGM presenting strips 62 each represent signals received from the 19 electrodes 55 (Figure 1) of the catheter 40. The IEGM presenting strips 62 for channels 8, 11, 17, and 18 show more activity in the negative voltage range than the IEGM presenting strips 62 for the other channels.

[0066] 4 also shows a legend 72 between the various colors in the IEGM presentation strip 62 and the corresponding voltage values ​​that provide a lookup for the physician 30 (FIG. 1). By way of example only, the top of the legend may be colored a dark red and the bottom of the legend may be colored a dark blue.

[0067] The IEGM presentation strips 62 may be shown one above the other on the display, thereby allowing many IEGM presentation strips 62 to be presented on a single screen.

[0068] In some embodiments, the IEGM presentation strip 62 may indicate other attributes of the signals, such as the rate of change of the respective signals or the resolution of the respective signals, instead of indicating voltage values ​​over time, by formatting the shapes 64 according to the value of the other attribute(s).

[0069] In other embodiments, the IEGM presentation strip 62 may indicate other attributes of the signals, such as the rate of change of each signal or the fraction of each signal, in addition to indicating the voltage values ​​over time, by formatting the shapes 64 according to the values ​​of other attribute(s) using one format type (e.g., using different transparency levels) or by formatting the shapes 64 according to the voltage values ​​using a different format type (e.g., using different colors).

[0070] Reference is now made to FIG. 5, which is a flow chart 74 including steps in a method of operation of the system 20 of FIG.

[0071] Catheter 40 (FIG. 1) is configured to be inserted (block 76) into a chamber of a living body's heart 26 (FIG. 1) and includes catheter electrodes 55 (FIG. 2) configured to contact tissue at respective locations within the chamber of heart 26.

[0072] Processing circuitry 41 (FIG. 1) is configured to receive the signal from catheter 40 and, in response to the signal, sample respective voltage values ​​of the signal at respective timing values ​​(block 78).

[0073] Processing circuitry 41 (FIG. 1) is optionally configured to derive a value for an attribute of a respective one of the signals in response to a respective one of the sampled voltage values ​​and a respective one of the timing values ​​(block 80). The attribute may be, for example, a rate of change of the sampled voltage values ​​or a resolution of a respective one of the signals.

[0074] The processing circuitry 41 (FIG. 1) is configured to, in response to the signals, render (block 82) on the display 27 (FIG. 1) respective intracardiac electrogram (IEGM) presentation strips 62 (FIG. 3) representative of electrical activity in the tissue sensed by the catheter electrodes 55 at the respective locations. Each IEGM presentation strip 62 includes a linear array of respective shapes 64 (FIG. 3) associated with a respective one of the timing values ​​and arranged in the temporal order of the respective one of the timing values. The filling of each shape 64 is formatted according to a respective one of the sampled voltage values ​​of a respective one of the signals sampled at the respective one of the timing values.

[0075] The formatting may be according to the sampled voltage values, or according to values ​​based on at least some of the sampled values. For example, the formatting may be based on the rate of change of the sampled voltage values, or on a fraction of each one of the signals. Thus, the IEGM presentation strip 62 may represent the rate of change or fraction of the sampled voltage values.

[0076] In some embodiments, processing circuitry 41 (FIG. 1) is configured to render on display 27 (FIG. 1) a respective IEGM presentation strip 62 in which the filling of the respective shapes 64 is at least partially colored in response to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at a respective one of the timing values. In other embodiments, processing circuitry 41 (FIG. 1) is configured to render on display 27 (FIG. 1) a respective IEGM presentation strip 62 in which the transparency of the filling of the respective shapes 64 is adjusted in response to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at a respective one of the timing values.

[0077] In some embodiments, processing circuitry 41 (FIG. 1) is configured to render on display 27 (FIG. 1) a respective IEGM presentation strip 62 in which the filling of each shape 64 is formatted according to a first formatting in response to a respective one of the sampled voltage values ​​of a respective one of the sampled signals at a respective one of the timing values, and in which the filling of each one of the shapes 64 is also formatted according to a second formatting in response to a derived value (derived in the step of block 80). The first formatting and the second formatting may be selected from any suitable formatting scheme, such as, for example, but not limited to, a color formatting or a transparency formatting. In some embodiments, the first formatting includes a color formatting and the second formatting includes a transparency formatting. In other embodiments, the first formatting includes a transparency formatting and the second formatting includes a color formatting.

[0078] In some embodiments, the processing circuit 41 (FIG. 1) is configured to render on the display 27 (FIG. 1) each IEGM presentation strip having at least one additional marker selected from any one of an alphanumeric symbol (e.g., a channel number in FIG. 4), another symbol (e.g., legend 72 in FIG. 4), a line (not shown), a dot (not shown), a time annotation (timing value in FIG. 4), a maximum value of the current data (not shown), or a pacing spike (not shown).

[0079] The term "about" or "approximately" as used herein with respect to any numerical value or range of numerical values ​​indicates a suitable dimensional tolerance that enables a portion of a component or a collection of components to function according to its intended purpose as described herein. More specifically, "about" or "approximately" may refer to a range of values ​​of ±20% of the recited value, for example, "about 90%" may refer to a range of values ​​of 71% to 99%.

[0080] Various different features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.

[0081] The embodiments described above are cited by way of example, and the present invention is not limited to what has been particularly shown and described in the above specification. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described in the above specification, as well as variations and modifications thereof not disclosed in the prior art that would occur to one skilled in the art upon reading the foregoing description.

[0082] [Embodiment] (1) A health care system, comprising: a catheter configured to be inserted into a chamber of a heart of a living subject and having catheter electrodes configured to contact tissue at respective locations within the chamber of the heart; A display and A processing circuit, receiving a signal from the catheter; In response to the signal, sampling respective voltage values ​​of said signals at respective timing values; rendering on the display a respective intracardiac electrogram (IEGM) presentation strip representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations, each of the IEGM presentation strips including a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in temporal order of the respective one of the timing values, the filling of the respective shapes being formatted according to a respective one of the sampled voltage values ​​of a respective one of the signals sampled at a respective one of the timing values; and a processing circuit configured to perform the steps of: (2) The system of embodiment 1, wherein the processing circuitry is configured to render the respective IEGM presentation strips on the display, the filling of the respective shapes being colored at least in part in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values. (3) The system of embodiment 1, wherein the processing circuitry is configured to render the respective IEGM presentation strips on the display, and wherein the transparency of the filling of the respective shapes is adjusted in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values. (4) The processing circuit, deriving a value for an attribute of a respective one of the signals in response to a respective one of the sampled voltage values ​​and a respective one of the timing values; Rendering each IEGM presentation strip on the display, the filling of the respective shape being formatted according to a first formatting in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values; rendering, wherein the filling of each one of the shapes is also formatted according to a second formatting in response to the derived values; The system of embodiment 1, configured to perform the following: (5) The system of claim 4, wherein the attribute is a rate of change of the sampled voltage value.

[0083] (6) The system of embodiment 4, wherein the attribute is a fractionation of each of the signals. (7) The system of embodiment 4, wherein the first formatting setting includes a color formatting setting and the second formatting setting includes a transparency formatting setting. (8) The system of embodiment 4, wherein the first formatting setting includes a transparency formatting setting and the second formatting setting includes a color formatting setting. (9) The system of embodiment 1, wherein the processing circuitry is configured to render on the display each of the IEGM presentation strips having at least one additional marker selected from any one of an alphanumeric symbol, another symbol, a line, a dot, a time annotation, a maximum value of current data, and a pacing spike. (10) A medical method comprising: receiving signals from a catheter configured to be inserted into a chamber of a heart of a living subject and having catheter electrodes configured to contact tissue at respective locations within the chamber of the heart; responsive to said signals, sampling respective voltage values ​​of said signals at respective timing values; and rendering on a display respective intracardiac electrogram (IEGM) presentation strips representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations, each of the IEGM presentation strips including a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in a temporal order of the respective one of the timing values, the filling of the respective shapes being formatted according to a respective one of the sampled voltage values ​​of a respective one of the signals sampled at a respective one of the timing values.

[0084] (11) The method of embodiment 10, wherein the rendering includes rendering the respective IEGM presentation strips on the display, the filling of the respective shapes being colored at least in part in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values. (12) The method of embodiment 10, wherein the rendering includes rendering the respective IEGM presentation strips on the display, wherein a transparency of the filling of the respective shapes is adjusted in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values. (13) The method of embodiment 10, further comprising deriving a value for an attribute of a respective one of the signals in response to a respective one of the sampled voltage values ​​and a respective one of the timing values, and wherein the rendering comprises rendering a respective IEGM presentation strip on the display, the filling of the respective shapes being formatted according to a first formatting in response to the respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values, and the filling of the respective one of the shapes also being formatted according to a second formatting in response to the derived value. 14. The method of claim 13, wherein the attribute is a rate of change of the sampled voltage values. (15) The method of embodiment 13, wherein the attribute is a distinction between each of the signals.

[0085] (16) The method of embodiment 13, wherein the first formatting setting includes a color formatting setting and the second formatting setting includes a transparency formatting setting. (17) The method of embodiment 13, wherein the first formatting includes a transparency formatting and the second formatting includes a color formatting. (18) The method of embodiment 10, wherein the rendering includes rendering the respective IEGM presentation strips on the display having at least one additional marker selected from any one of an alphanumeric symbol, another symbol, a line, a dot, a time annotation, a maximum value of current data, and a pacing spike. (19) A software product including a non-transitory computer-readable medium having program instructions stored thereon, the instructions, when read by a central processing unit (CPU), causing the CPU to: receiving signals from a catheter configured to be inserted into a chamber of a heart of a living subject and having catheter electrodes configured to contact tissue at respective locations within the chamber of the heart; responsive to said signals, sampling respective voltage values ​​of said signals at respective timing values; and rendering on a display respective intracardiac electrogram (IEGM) presentation strips representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations, each of the IEGM presentation strips including a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in a temporal order of the respective one of the timing values, the filling of the respective shapes being formatted according to a respective one of the sampled voltage values ​​of a respective one of the signals sampled at a respective one of the timing values.

Claims

1. 1. A health care system comprising: a catheter configured to be inserted into a chamber of a heart of a living subject and having catheter electrodes configured to contact tissue at respective locations within the chamber of the heart; A display and A processing circuit, receiving a signal from the catheter; In response to the signal, sampling respective voltage values ​​of said signals at respective timing values; rendering on the display respective intracardiac electrogram (IEGM) presentation strips representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations, each of the IEGM presentation strips including a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in temporal order of the respective one of the timing values, the filling of the respective shapes being formatted according to a respective one of the sampled voltage values ​​of a respective one of the signals sampled at a respective one of the timing values; and a processing circuit configured to: The processing circuitry comprises: deriving a value for an attribute of a respective one of the signals in response to a respective one of the sampled voltage values ​​and a respective one of the timing values; Rendering each IEGM presentation strip on the display, rendering the filling of the respective shapes formatted according to a first formatting in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values ​​and formatted according to a second formatting in response to values ​​for the derived attributes; 1. A health care system comprising:

2. 2. The system of claim 1, wherein the processing circuitry is configured to render the respective IEGM presentation strips on the display, the filling of the respective shapes being colored at least in part in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values.

3. 2. The system of claim 1, wherein the processing circuitry is configured to render the respective IEGM presentation strips on the display, the transparency of the filling of the respective shapes being adjusted in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values.

4. The system of claim 1 , wherein the attribute is a rate of change of the sampled voltage values.

5. The system of claim 1 , wherein the first formatting includes a color formatting and the second formatting includes a transparency formatting.

6. The system of claim 1 , wherein the first formatting includes a transparency formatting and the second formatting includes a color formatting.

7. 2. The system of claim 1, wherein the processing circuitry is configured to render on the display the respective IEGM presentation strips having at least one additional marker selected from any one of the following: an alphanumeric symbol, another symbol, a line, a dot, a time annotation, a maximum value of current data, and a pacing spike.

8. A method of operating a medical system, comprising: receiving signals from a catheter configured to be inserted into a chamber of a heart of a living subject and having catheter electrodes configured to contact tissue at respective locations within the chamber of the heart; responsive to said signals, sampling respective voltage values ​​of said signals at respective timing values; rendering on a display respective intracardiac electrogram (IEGM) presentation strips representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations, each of the IEGM presentation strips including a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in temporal order of the respective one of the timing values, the filling of the respective shapes being formatted according to a respective one of the sampled voltage values ​​of a respective one of the signals sampled at the respective one of the timing values; The method of operating a medical system further comprising the processing circuitry deriving a value for an attribute of a respective one of the signals in response to a respective one of the sampled voltage values ​​and a respective one of the timing values, and wherein the rendering comprises the processing circuitry rendering a respective IEGM presentation strip on the display, the filling of the respective shapes being formatted according to a first formatting in response to the respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values, and also formatted according to a second formatting in response to the derived value for the attribute.

9. 9. The method of operating a medical system of claim 8, wherein the rendering includes the processing circuitry rendering the respective IEGM presentation strips on the display, the filling of the respective shapes being colored at least in part in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values.

10. 9. The method of operating a medical system of claim 8, wherein the rendering includes the processing circuitry rendering the respective IEGM presentation strips on the display, the transparency of the filling of the respective shapes being adjusted in response to the respective ones of the sampled voltage values ​​of the respective ones of the signals sampled at the respective ones of the timing values.

11. The method of claim 8 , wherein the attribute is a rate of change of the sampled voltage values.

12. The method of claim 8 , wherein the first formatting includes a color formatting and the second formatting includes a transparency formatting.

13. The method of claim 8 , wherein the first formatting includes a transparency formatting and the second formatting includes a color formatting.

14. 10. The method of claim 8, wherein the rendering includes rendering the respective IEGM presentation strips on the display having at least one additional marker selected from any one of an alphanumeric symbol, another symbol, a line, a dot, a time annotation, a maximum value of current data, and a pacing spike.

15. A non-transitory computer readable medium having program instructions stored thereon, the instructions, when read by a central processing unit (CPU), causing the CPU to: receiving signals from a catheter configured to be inserted into a chamber of a heart of a living subject and having catheter electrodes configured to contact tissue at respective locations within the chamber of the heart; responsive to said signals, sampling respective voltage values ​​of said signals at respective timing values; deriving a value for an attribute of a respective one of the signals in response to the respective one of the sampled voltage values ​​and the respective one of the timing values, wherein the rendering comprises rendering on the display respective intracardiac electrogram (IEGM) presentation strips representative of electrical activity in the tissue sensed by the catheter electrodes at the respective locations, each of the IEGM presentation strips including a linear array of respective shapes associated with a respective one of the timing values ​​and arranged in temporal order of the respective one of the timing values, the filling of the respective shapes being formatted in response to a respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values, and deriving a value for an attribute of the respective one of the signals in response to the respective one of the sampled voltage values ​​and the respective one of the timing values, wherein the rendering comprises rendering on the display respective IEGM presentation strips, the filling of the respective shapes being formatted according to a first formatting in response to the respective one of the sampled voltage values ​​of the respective one of the signals sampled at the respective one of the timing values ​​and according to a second formatting in response to the derived value for the attribute.

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