Functional impact of vascular lesions

Abstract

To disclose methods and apparatus for determining a functional impact of vascular lesions.SOLUTION: An example method includes calculating estimates of a single functional blood flow metric (for example, fractional flow reserve calculated from angiographic images) for multiple locations (301, 302, 304, 308) in each of a plurality of connected vascular branches. The method includes converting these estimates into FFR impact scores, which are indicative of the overall impact of occlusive vascular disease on the connected vascular branches.SELECTED DRAWING: Figure 2A

Description

[Technical Field]

[0001] In some embodiments thereof, the present invention relates to the field of vascular imaging, and in particular to determining vascular status using vascular images. [Background technology]

[0002] Cardiac catheterization is a diagnostic test that allows a physician to evaluate coronary artery narrowing based on angiograms and determine the need for further treatment. Additional imaging procedures, such as intravascular ultrasound (IVUS) and fractional flow reserve (FFR), may be performed in conjunction with cardiac catheterization to obtain detailed images of the vessel walls. Following the diagnostic procedure, various treatment options are considered. Treatment may include medication, coronary angioplasty (with or without coronary stenting), or coronary artery bypass surgery. Treatment is aimed at reducing or eliminating symptoms and reducing the risk of heart attack.

[0003] Fractional flow reserve (FFR) is a blood pressure management technique used to measure the blood pressure gradient across a coronary artery stenosis to determine the ratio between the maximum achievable blood flow in a diseased coronary artery and the theoretical maximum blood flow in a normal coronary artery. The use of FFR information potentially improves PCI decision-making and outcomes. For example, the FAME trial (Non-Patent Document 1) randomized 1005 patients to FFR-guided angiography using a cutoff point of ≦80 as the basis for deciding on treatment (with or without PCI) versus presumptive visual assessment (angiography) alone. Highlights of the study findings include the following: Thirty percent of patients who were presumed to need a stent based on visual assessment did not need a stent based on FFR assessment. The number of stents used was approximately one-third higher when PCI decisions were based on angiography alone versus FFR (2.7 vs. 1.9, P<0.001). One-year MACE (major adverse cardiac events) was higher in the visual angiography arm compared with the FFR arm (18.3% vs. 13.2%, P<0.02). The mean cost per procedure for patients evaluated with FFR was reduced by 11.2% compared to angiography alone. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Tonino Pal et al., "Fractional Flow Reserve versus Angiography for Guiding Percutaneous Coronary Intervention," N Engl J Med, January 15, 2009, Vol. 360, pp. 213-224 Summary of the Invention [Means for solving the problem]

[0005] In some embodiments of the present disclosure, 1. A method for estimating a clinical state of a vascular segment, comprising: receiving a fractional flow reserve (FFR) map that assigns a plurality of FFR values ​​to specific locations on each of a plurality of vascular segments of a vascular tree representing the vascular portion; and calculating an FFR impact score using the mapped FFR values, a component of the FFR impact score discarding the mapping of FFR values ​​to the particular location; A method is provided which includes:

[0006] In some embodiments, the map of FFR assigns consecutive or near-consecutive FFR values ​​to the specific locations.

[0007] In some embodiments, the map of FFR includes at least five FFR values ​​for each of at least four vessel segments.

[0008] In some embodiments, the map of FFR represents the contribution to reduced flow potential from upstream locations common to each of the identified locations.

[0009] In some embodiments, the vascular tree models multiple vascular ranges of vascular portions connected at branching points, with each vascular segment extending between two of the origin of the vascular tree, a first vascular branching point, a second vascular branching point, and an unconnected end of the vascular tree.

[0010] In some embodiments, the FFR impact score includes multiple score elements, each of which discards the mapping of the FFR value to the particular location but retains its association with a particular one of the plurality of vessel segments.

[0011] In some embodiments, the plurality of score elements includes a total drop score for each of the plurality of vessel segments, the total drop score representing a total drop in FFR along the vessel segment from a reference value representing non-occluded vasculature.

[0012] In some embodiments, the method further comprises assigning an occluded or non-occluded status to each of the plurality of vessel segments based on at least the total drop score for that segment; Counting the number of occluded vessel segments; and Providing the total number as a hypervascular score, which is a score element of the FFR impact score; Includes:

[0013] In some embodiments, the plurality of score elements includes, for each of the plurality of vessel segments, a maximum drop score representing the maximum drop in FFR along the vessel segment along a defined portion of the vessel segment that is shorter than the entire vessel segment.

[0014] In some embodiments, the defined portion is about 10 mm3 and about 100 mm 3 This is the distance within which the blood volume falls within the range between

[0015] In some embodiments, the defined portion is about 40 mm 3 This is the distance that can accommodate the blood volume of

[0016] In some embodiments, the method further comprises assigning an occluded or non-occluded status to each of the plurality of vessel segments based on at least the maximum drop score for that segment; Counting the number of occluded vessel segments; and Providing the total number as a hypervascular score, which is a score element of the FFR impact score; Includes:

[0017] In some embodiments, the plurality of score elements includes, for each of the plurality of vessel segments, a diffusivity score that represents a measure of how widely distributed along that vessel segment are the lesions that contribute to the total drop in FFR.

[0018] In some embodiments, calculating the vascular drop diffusivity score comprises determining the extent to which the maximum drop score differs from the total drop score.

[0019] In some embodiments, calculating the vascular drop diffusivity score comprises calculating a ratio of the total drop score to the maximum drop score.

[0020] In some embodiments, the plurality of score elements includes a severity score representing a weighted average of FFR at all positions within the vascular tree, with positions at greater distances from the origin of the vascular tree being weighted downward.

[0021] In some embodiments, the plurality of score elements includes one or more score elements associated with a segment including the left main coronary artery up to a first bifurcation point of the left main coronary artery represented in the vascular tree.

[0022] In some embodiments, the FFR impact score includes a sorted value chart score element that represents the FFR values ​​of each of the multiple vascular segments in a composite value sort order, such that values ​​from different vascular segments are interleaved with each other.

[0023] In some embodiments, the method includes displaying the sorted value chart score elements as a color-coded pie chart.

[0024] In some embodiments, the FFR impact score includes histogram chart score elements representing the FFR values ​​for each of the plurality of vessel segments in a composite histogram, the contribution of each FFR value to the histogram being weighted according to the size of the vessel volume within which that FFR value occurs.

[0025] In some embodiments, the FFR impact score includes a score component that describes lesion length based on the distance over which FFR values ​​continuously decrease.

[0026] In some embodiments, the FFR impact score includes score elements that describe lesion geometry as one or more of: including both the main vessel and a side branch; including the main vessel and at least two of its branches; occurring within an aortic ostial vessel segment; occurring adjacent to a bent region of the vasculature; or occurring within a bent region of the vasculature.

[0027] In some embodiments, the method includes adjusting the FFR impact score based on a modified map of FFR modified according to one or more of automated virtual stenting, manual stent selection, data measured after stent placement, and data measured through multiple diagnostic procedures.

[0028] In some embodiments, the method includes comparing the FFR impact score to a second FFR impact score calculated according to the method of claim 1 and estimating a rate of progression of the vascular disease.

[0029] In some embodiments, the method includes scheduling a further diagnostic procedure based on the estimation.

[0030] In some embodiments, the method includes planning a treatment procedure based on the FFR impact score.

[0031] In some embodiments, the method includes choosing between OMT and PCI based on the FFR impact score.

[0032] In some embodiments, the method includes choosing between PCI and CABG treatment based on the FFR impact score.

[0033] In some embodiments, the method includes planning at least one of the number, location, and / or type of stents to be placed based on the FFR impact score.

[0034] In some embodiments, the method includes planning at least one of the number and / or location of CABG grafts to be placed based on the FFR impact score.

[0035] In some embodiments of the present disclosure, there is provided a method for estimating a clinical state of a vascular segment, comprising: receiving a fractional flow reserve (FFR) map that assigns a plurality of FFR values ​​to specific locations on each of a plurality of vascular segments of a vascular tree representing the vascular portion; and calculating an FFR impact score using the mapped FFR values, the FFR impact score including a component comparing a total drop in FFR along at least one of the vessel segments to a maximum drop in FFR along that vessel segment; A method is provided which includes:

[0036] In some embodiments of the present disclosure, there is provided a method for estimating a clinical state of a vascular segment, comprising: receiving a fractional flow reserve (FFR) map that assigns a plurality of FFR values ​​to specific locations on each of a plurality of vascular segments of a vascular tree representing the vascular portion; and calculating an FFR impact score using the mapped FFR values, the FFR impact score comprising a graph combining the individual FFR values ​​from the plurality of vessel segments into a display in which at least some of the individual FFR values ​​are shown in positions on the graph that are not adjacent to any other FFR values ​​obtained from adjacent vessel locations; A method is provided which includes:

[0037] In some embodiments of the present disclosure, a system is provided that includes a processor configured to perform the above-described method.

[0038] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, exemplary methods and / or materials are described below. In case of conflict, the present patent specification (including definitions) will control. Furthermore, the materials, methods, and examples are illustrative only and are not intended to be necessarily limiting.

[0039] As will be appreciated by those skilled in the art, aspects of the present disclosure may be embodied as a system, a method, or a computer program product. Accordingly, aspects of the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, microcode, etc.), or an embodiment combining software and hardware aspects (e.g., a method may be implemented using "computer circuitry"), all of which may be generally referred to herein as a "circuit," "module," or "system." Furthermore, some embodiments of the present disclosure may take the form of a computer program product embodied in one or more computer-readable medium(s) having computer-readable program code embodied therein. Implementation of the methods and / or systems of some embodiments of the present disclosure may involve performing and / or completing selected tasks manually, automatically, or a combination thereof. Furthermore, depending on the actual equipment and materials of some embodiments of the methods and / or systems of the present disclosure, some selected tasks may be implemented by hardware, software, firmware, and / or a combination thereof, e.g., using an operating system.

[0040] For example, hardware for performing selected tasks according to some embodiments of the present disclosure may be implemented as a chip or circuit. As software, selected tasks according to some embodiments of the present disclosure may be implemented as software instructions executed by a computer using any suitable operating system. In some embodiments of the present disclosure, one or more tasks performed in the method and / or by the system are performed by a data processor (also referred to herein as a "digital processor," referring to a data processor that operates with digital bits), such as a computing platform for executing instructions. Optionally, the data processor includes volatile memory for storing instructions and / or data, and / or non-volatile storage, e.g., a magnetic hard disk and / or removable storage, for storing instructions and / or data. Optionally, network connectivity is provided as well. Optionally, a display and / or user input devices, such as a keyboard or mouse, are provided as well. Any of these implementations are referred to herein more broadly as instances of computer circuitry.

[0041] Any combination of one or more computer-readable media may be used for some embodiments of the present disclosure. The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination thereof. More specific examples (non-limiting list) of computer-readable storage media include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. A computer-readable storage medium may contain or store information for use by such programs, e.g., data structured to be recorded by the computer-readable storage medium in a manner that allows the computer programs to access the information, e.g., as one or more tables, lists, arrays, data trees, and / or other data structures. Computer-readable storage media that record data in a form obtainable as a collection of digital bits are also referred to herein as digital memory. It should be understood that in some embodiments, a computer-readable storage medium is also optionally used as a computer-writable storage medium, provided that the computer-readable storage medium is not inherently read-only and / or is not in a read-only state.

[0042] As used herein, a data processor is "configured" to perform data processing activities to the extent that it is coupled to a computer-readable memory, retrieves instructions and / or data therefrom, processes them, and / or stores the results of the processing in the same or another computer-readable storage memory. The processing performed (optionally on data) is specified by the instructions. Processing acts may additionally or alternatively be referred to by one or more other terms, such as comparing, estimating, determining, calculating, identifying, associating, storing, analyzing, selecting, and / or transforming. For example, in some embodiments, a digital processor receives instructions and data from a digital memory, processes the data in accordance with the instructions, and / or stores the results of the processing in the digital memory. In some embodiments, "providing" the results of the processing includes one or more of transmitting, storing, and / or presenting the results of the processing. Presenting optionally includes showing the results on a display, indicating them with sound, printing them on a printout, or otherwise making the results available to human perception.

[0043] A computer-readable signal medium may include a propagated data signal having computer-readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electromagnetic, optical, or any suitable combination thereof. A computer-readable signal medium may be any computer-readable medium that is not a computer-readable storage medium and that can communicate, propagate, or convey a program for use by or in connection with an instruction execution system, apparatus, or device.

[0044] The program code and / or data used thereby contained in the computer readable medium may be transmitted using any suitable medium, including but not limited to wireless, wired, fiber optic cable, RF, etc., or any suitable combination thereof.

[0045] Computer program code for carrying out operations for some embodiments of the present disclosure may be written in any combination of one or more programming languages, including object-oriented programming languages ​​(such as Java, Smalltalk, C++, etc.) and conventional procedural programming languages ​​(such as the "C" programming language or similar programming languages). The program code may execute entirely on the user's computer, partially on the user's computer, as a standalone program package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter case, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), and the connection may also be made to an external computer (e.g., via the Internet using an Internet Service Provider).

[0046] Some embodiments of the present disclosure may be described below with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions (which execute via a processor of the computer or other programmable data processing apparatus) create means for implementing the functions / acts identified in one or more blocks of the flowcharts and / or block diagrams.

[0047] These computer program instructions may be recorded in a computer-readable medium that can instruct a computer, other programmable data processing device, or other device to function in a particular way, such that the instructions stored in the computer-readable medium create an article of manufacture that includes instructions that implement the functions / acts identified in one or more blocks of the flowcharts and / or block diagrams.

[0048] The computer program instructions may be loaded into a computer, other programmable data processing device, or other device to cause the computer, other programmable device, or other device to perform a series of operational steps to generate a computer-implemented process, such that the instructions, executing on the computer or other programmable device, provide a process for implementing the functions / acts identified in one or more blocks of the flowcharts and / or block diagrams. [Brief explanation of the drawings]

[0049] Several embodiments of the present disclosure are described herein, by way of example only, with reference to the accompanying drawings. While specific reference will be made to the detailed drawings, it is emphasized that the details shown are by way of example and are for purposes of describing and discussing embodiments of the present disclosure. However, it will be apparent to those skilled in the art from the description taken together with the drawings how embodiments of the present disclosure may be practiced.

[0050] [Figure 1A] FIG. 1A is a schematic flow chart of a method for generating an FFR impact score according to some embodiments of the present disclosure. [Figure 1B] FIG. 1B is a schematic flow chart of a method for generating an FFR impact score according to some embodiments of the present disclosure. [Figure 2A] FIG. 2A shows a display result of a method for calculating an FFR impact score according to some embodiments of the present disclosure. [Figure 2B] FIG. 2B shows a display result of a method for calculating an FFR impact score according to some embodiments of the present disclosure. [Figure 2C] 2C shows a representation of a method for calculating an FFR impact score according to some embodiments of the present disclosure. [Figure 3A] FIG. 3A illustrates a schematic representation of FFR impact scores (in the form of a pie chart constructed as previously described for pie charts) in relation to disease treatment options, according to some embodiments of the present disclosure. [Figure 3B] FIG. 3B schematically illustrates FFR impact scores (in the form of a pie chart constructed as previously described for pie charts) in relation to disease treatment options, according to some embodiments of the present disclosure. [Figure 3C] FIG. 3C illustrates a schematic representation of FFR impact scores (in the form of a pie chart constructed as previously described for pie charts) in relation to disease treatment options, according to some embodiments of the present disclosure. [Figure 3D] FIG. 3D schematically illustrates FFR impact scores (in the form of a pie chart constructed as previously described for pie charts) in relation to disease treatment options, according to some embodiments of the present disclosure. [Figure 4] FIG. 4 shows a display result of a method for calculating an FFR impact score according to some embodiments of the present disclosure. [Figure 5] FIG. 5 shows an example of a screen output provided by a system compatible with calculating and displaying a total FFR score, according to some embodiments of the present disclosure. [Figure 6] FIG. 6 is a schematic representation of a system for calculation of an FFR impact score according to some embodiments of the present disclosure. [Figure 7] FIG. 7 is a schematic representation of the data and processing instruction components of a system for calculation of an FFR impact score, according to some embodiments of the present disclosure. [Figure 8] FIG. 8 is a schematic flow chart of the calculation of FFR impact score components according to some embodiments of the present disclosure. [Figure 9] FIG. 9 illustrates a schematic diagram of a method for calculating the mean severity score according to some embodiments of the present disclosure. [Figure 10] FIG. 10 is a schematic flow chart of a method for graphing received mapped FFR values ​​according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0051] A broad aspect of some embodiments of the present disclosure relates to metrics that summarize the functional state of the vascular tree to provide information that serves as a direct input into medical intervention decision-making. In some embodiments, the summary metric summarizes a measure of fractional flow reserve (FFR).

[0052] As the term "FFR" is used herein, such FFR results represent the measured and / or estimated ratio of the current blood flow (i.e., expressed in units of volume per unit time) through a particular region of a potentially occluded blood vessel to the ideal blood flow through the same location in an otherwise equivalent, unoccluded vessel. As the abbreviation FFR (fractional flow reserve) implies, FFR results are an indication of what proportion of "reserve" blood flow (interfered with by vascular occlusion) could, in principle, be restored to the vessel if the vessel were somehow restored (e.g., by treatment) to a completely unoccluded state. The more the FFR value decreases, the more blood flow is "reserved" in this sense, and the potentially more severe the ischemia.

[0053] As defined above, a "true" FFR result is an ideal, and an actual FFR result is an approximation of that ideal that is bound by real-world limitations. In particular, because it is not possible to practically utilize a conceptual "unoccluded vessel" to compare with a real, diseased version of the same vessel, it must be provided by a series of calculations and / or assumptions. Practical methods for measuring and / or estimating FFR vary based in part on how the actual measurements are used to approximate the ideal value. As used herein, measured FFR, estimated FFR, or FFR value (including mapped FFR values, as described below) is intended to encompass the results of all such measurement and / or estimation methods.

[0054] It should be understood that values ​​that provide inferential capacity and functional information about the flow restoration of the FFR but that are not themselves expressed as a percentage (eg, due to renormalization) are also included herein as FFR values.

[0055] It should be further understood that this definition of FFR is a superset of a previously developed in vivo pressure sensor-based measurement, also referred to as FFR (which will be referred to herein as "pressure sensor-based FFR" to distinguish it from the "FFR" defined above). A pressure sensor-based FFR result represents the ratio of pressure downstream of a baseline location to the pressure at that baseline location, where two locations are sufficiently close in location that the pressures that would be measured at those locations in a healthy, unoccluded vessel can be expected to be nearly equal (e.g., a ratio of 0.8 to 1 or greater). If this ratio is less than about 0.8, it is believed that there is an occlusion between the two measurement locations that may be causing ischemia. Pressure is treated as a proxy for blood flow based on known blood flow equations that describe the relationship between blood flow, pressure, and flow resistance.

[0056] Pressure sensor-based FFR measurements, interpreted as estimating the "true" fractional flow reserve, may also be understood to rely on several assumptions that tend to simplify the true situation. For example, these assumptions include that the upstream site itself is located without any significant upstream obstruction (as actually practiced in this technique, the upstream sensor is placed at the inflow site) and / or that any downstream obstructions are relatively free of obstruction. Pressure may decrease along the unobstructed vessel anyway if the distance is long enough. Overall, pressure sensor-based FFR measurements tend to show the best agreement with the FFR defined above when measured from two nearby locations separated by a single, relatively focal lesion that partially obstructs blood flow.

[0057] Image-based FFR, on the other hand, potentially has the ability to estimate fractional flow reserve continuously along an entire vessel segment and even between several different vessel segments of the same vascular tree. Image-based FFR is optionally calculated by other means, such as by using computational fluid dynamics (CFD) to obtain an estimate of pressure along the vessel (pressure is used to calculate FFR similarly to pressure sensor-based FFR). In another example, image-based FFR is calculated by comparing CFD-determined blood flow in a stenosis and hypothetical revascularization model of the same vasculature.

[0058] Accordingly, image-based FFR allows FFR values ​​to be assigned not only to a single region between two measurement points, but to various regions along an entire vessel segment, optionally continuously along the entire vessel segment, and optionally to multiple such vessel segments.

[0059] As used herein, the term "vascular tree" is used to refer to a model of a vascular portion (e.g., part of a patient's particular vascular anatomy), and a "vascular segment" is a portion of the vascular tree. In particular, a vascular tree models multiple vascular regions connected to each other at branching points. A vascular segment can be defined as representing one or more of these vascular regions, where each vascular segment extends between two of the following: The origin of the vascular tree (e.g., the aortic root in the case of a vascular tree modeling the cardiac arterial vasculature) First vascular branching point Second blood vessel branching point Disconnected ends of the vascular tree

[0060] An aspect of some embodiments of the present disclosure relates to the use of an estimate of a single functional metric calculated for multiple locations in each of multiple connected vascular branches as an estimate of the overall effect of occlusive vascular disease in the connected vascular branches.

[0061] WO 2014 / 064702 describes the use of various vascular measurements automatically collected from angiographic images to provide input to a vascular state scoring tool (VSST), such as the SYNTAX score. The SYNTAX score is an angiographic tool used to characterize coronary vascular disease status and predict outcomes of coronary interventions based on anatomical complexity. The SYNTAX score grades the complexity of coronary artery disease, allowing for comparisons between patients and more efficient communication between physicians. This scoring algorithm has been recommended by professional associations of cardiac care medical professionals as an integral part of the decision-making process in complex cardiovascular cases. The SYNTAX score questionnaire requires input on several different vascular metrics, such as lesion location and size, including the degree of obstruction (e.g., a threshold of >50% obstruction is specified in the scoring instructions), shape and length, the presence of thrombus, and / or vessel tortuosity. Alternatives to the VSST approach potentially include, for example, a "Functional SYNTAX Score" (which integrates physiological measurements, such as blood flow capacity, vascular elasticity, vascular autoregulation, and / or other measures of vascular function, into a SYNTAX score-like tool) or a "Clinical SYNTAX Score" (which integrates clinical variables, such as patient history and / or systemic and / or organ-specific test results, into a SYNTAX score-like tool). Examples also include the AHA classification of coronary artery branch segments modified for the ARTS trial, the Riemann score, the ACC / AHA lesion classification system, the total occlusion classification system, and / or the Duke and ICPS classification systems for bifurcation lesions.

[0062] Surprisingly, the inventors have come to the novel realization that a continuous or near-continuous map of FFR over the vasculature potentially has the ability to replace multi-parameter VSST by converting the map of FFR estimates into a score built on that single parameter. This score (which may, for example, be scalar, vector, tabular, and / or graphical in nature) is referred to herein as an "FFR impact" score.

[0063] The transformation, in some embodiments, involves de-emphasizing (de-emphasizing) certain information that is dependent on the details of the subject's vascular geometry and / or the completeness of the vascular model, while emphasizing information about the disease state itself. In particular, the transformation begins with a map of FFRs and extracts FFR values ​​from the context of specific locations along the vessel extent to create a score that does not include this association. In some embodiments, the transformation uses multiple FFR values ​​(e.g., at least 3, 5, 10, 20, 30, or more FFR values) from each of multiple (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, or more) vessel segments defined between branch termini, proximal origins, and / or vessel bifurcation locations (e.g., bifurcations or trifurcations). In some embodiments, the multiple specific locations are defined contiguously or nearly contiguously within the meaning of the following terms:

[0064] As used herein, "nearly continuous" refers to, for example, at least 10, 20, 30, or more estimates per vessel segment between identified major bifurcation nodes, and more specifically, estimates using data acquired with sufficient resolution to identify the length of the vessel segment through which the FFR changes (decreases), i.e., defining not just two points on either side of a lesion, but also the beginning and end of the lesion. As used herein, "continuous" means that an FFR estimate is provided for each unit of representation resolution (e.g., each pixel) along the vessel length, and is optionally calculated using a continuous function and / or a collection of multiple adjacent interpolating functions, each of which is itself a continuous function. Continuous and near-continuous representations of FFR (also referred to herein as "maps") potentially have the ability to provide the basis for FFR impact score calculations. As used herein, the term "FFR map" or, equivalently, "mapped FFR" refers to a representation of FFR that maps FFR values ​​to discrete, specific locations along the vessel segment in a continuous or near-continuous manner.

[0065] As used herein, vascular maps that themselves represent non-FFR values ​​(e.g., other measures of vascular function and / or status) that are converted to individual FFR values ​​in the process of calculating an FFR impact score are also considered to belong to the category of "FFR maps," and the converted individual FFR values ​​are also considered to belong to the category of FFR maps, e.g., the conversion itself defines part of the mapping of FFR values ​​to vascular locations.

[0066] One way to conceptualize the relevance of FFR to disease complexity is to consider two related but independent aspects of vascular disease assessment as part of a treatment plan.

[0067] One such aspect is disease severity. Mapped FFR values ​​can be summarized into at least two different severity metrics: regional and global. The global measure simply asks, "What is the total drop in blood flow" compared to an ideal, healthy vessel. This is, for example, the FFR value measured at the end of the vessel. The regional measure essentially asks, "Is there a major lesion?" This translates to, "What is the worst single drop in blood flow," captured, for example, as the maximum drop within a window. Severe cases of vascular disease may include severe focal stenosis, a condition that significantly contributes to a state of reduced blood flow and, if further obstruction develops, can lead to dangerous acute ischemia. Another aspect of severity, in some embodiments of the invention, is a calculation of how much of the vascular tree is experiencing a reduction in FFR and to what extent. This can be calculated, for example, as the relative area above the curve (and below the maximum FFR value of 1) when all FFR values ​​are removed from their mapped locations and graphed in sorted order. The larger the relative area, the greater the influence of the FFR. This represents a summation-type (or "integral") use of FFR data to assess disease state.

[0068] Another aspect is the treatability of the disease. Part of the currently accepted standard of care (for appropriate patients) is stenting, which serves to open and hold open focal areas of vascular stenosis. However, if the cause of the vascular stenosis is not primarily due to a focal configuration, a vascular stent may not provide sufficient blood flow restoration. Using mapped FFR, it is possible to distinguish between two cases where the total drop within the vessel is the same, but one is continuous and / or in multiple stages, while the other is at only one or two focal locations of the main lesion. In this case, the calculation may include, for example, obtaining the ratio (optionally, after appropriate normalization and / or offset) of the total FFR drop along a vessel to the maximum FFR drop across a defined volume along that vessel. The lower the raw ratio or an appropriately normalized ratio, the more FFR drop occurs at the location of the maximum FFR drop, and the more focal the lesion. The higher the raw ratio, the more likely the stenosis is distributed along the vessel. In some embodiments, operations other than arithmetic division are used, such as non-linear operations, look-up tables, or machine learning results that tie together the total and maximum FFR drop to a database of patient outcomes.

[0069] To a first approximation, in some embodiments, the mapped FFR is converted into an FFR impact score by combining "derivative" (or "slope") type information, which indicates the localization of the stenotic lesion (the larger the magnitude of the derivative, the more localized it is), with "integral" (or "summation") type information, which indicates the overall severity of the impact on perfusion and ischemia. Each of these three types of information is optionally normalized relative to the others as part of the normalization.

[0070] Finally, it may be noted that the calculations that can be performed on the mapped FFR to generate an FFR impact score correspond to some of the types of parameters involved in VSST, such as the SYNTAX score. The focality determined from the mapped FFR estimate can be understood as a surrogate for lesion length. The total FFR drop is a metric of occlusion. The integral of the FFR drop is a metric of where the lesion occurs; the closer to the carotid artery (in terms of distance along the vessel), the larger the tissue area affected by restricted perfusion. Finally, when these metrics are compiled for each of multiple vessel segments on different major branches of the vascular tree, a score status for the entire vascular tree can be determined.

[0071] To the extent that the FFR impact score potentially "reaches" many of the same fundamental issues of lesion complexity that the SYNTAX score seeks to capture, it may also potentially be found to be of similar value for guiding treatment and / or predicting treatment outcomes. At the same time, the FFR impact score has several potential advantages over scoring methods such as the SYNTAX score. By relying primarily (and optionally only) on a single fundamental type of input data (FFR), the FFR impact score avoids the problem of determining how to jointly weigh several disparate inputs. Calculations using FFR avoid the heuristics of the SYNTAX score, which may not be reproducibly followed by all scores. Even if scoring is automated, reliance on threshold conditions can introduce significant noise into a single score. For example, the SYNTAX score, while amenable to human decision-making, includes threshold-defined estimates (at least 50% occluded) that are potentially subject to scorer "noise," particularly for values ​​near the threshold cutoff. This noise has a real impact on outcome, as high-stakes decisions must be made about individual cases, but there is no method available to "average out" the noise error.

[0072] Furthermore, while SYNTAX score calculations can be automated, they were originally designed for human calculation. The FFR impact score uses a metric that is inherently automated. One example of the difference this creates is that human-calculated scoring methods tend to "throw data out early" because they do not need to be recorded or recursive. Positive / negative and / or roughly graded decisions are easier for human scorers to handle. Because automated methods may retain any amount of intermediate result data with any appropriate precision, even if a simple score is required as the final result, such simplifications may occur at a later step, potentially as the final step to generate the vascular status score itself.

[0073] Before describing at least one embodiment of the present disclosure in detail, it is to be understood that the present disclosure is not necessarily limited in its application to the structural details and arrangements of components and / or methods set forth in the following description and / or illustrated in the drawings. Features described in this disclosure (including features of the present invention) are capable of other embodiments and of being practiced or carried out in various ways.

[0074] How to generate an FFR impact score Reference is now made to FIGS. 1A-1B, which are schematic flow charts of methods for generating an FFR impact score according to some embodiments of the present disclosure.

[0075] In some embodiments, an angiographic image is received at block 102. In some embodiments, the angiographic image includes a plurality of X-ray angiograms. In some embodiments, the angiographic image has another source, for example, CT, MRI, or another imaging modality. In particular, references herein to "two-dimensional imaging" (and the resulting "two-dimensional image") relate to angiograms obtained by projection imaging techniques in which a sensor is placed at an imaging plane and images radiant energy (e.g., X-rays) received at the imaging plane after passing through a body containing the tissue being imaged from a radiant energy source.

[0076] Angiographic images capture a branching collection of interconnected vessel segments that comprise a portion of the vasculature, which in some embodiments is a portion of the cardiac arterial vasculature.

[0077] In some embodiments, at block 104, the imaged vessels shown in the angiographic image are converted into an angiographic model including multiple connected vessels, referred to herein as a "vascular tree." The longitudinal extents of segments in the vascular tree model correspond to the longitudinal extents of corresponding segments of the imaged vessel. Additionally, the cross-sectional geometry of the imaged vessel is represented in the model, optionally parameterized (e.g., parameterized as radius, diameter, and / or area), and optionally more fully described, such as by specifying its complete cross-sectional shape. Methods for generating such models are described, for example, in International Publication No. WO 2014 / 111930, filed January 15, 2014, the entire contents of which are incorporated herein by reference.

[0078] In some embodiments, regions of the vascular tree model determined to be stenotic (e.g., stenotic and / or at least partially occluded) in block 106 are "revascularized" in a modified model based on the vascular tree model. In the "revascularized" regions, the vessel cross-sectional information is modified in an appropriate manner to resemble the state without the stenosis. In some embodiments, the revascularized cross-section is recovered by interpolating values ​​between relatively unoccluded regions upstream and / or downstream of the stenosis itself. In some embodiments, other data, such as atlas information and / or consistency constraints, are used to recover the revascularized diameter. Methods for generating revascularized vascular tree models are described, for example, in International Publication No. WO 2014 / 111929, filed January 15, 2014, which is incorporated herein by reference in its entirety.

[0079] In some embodiments, an FFR value for the entire vascular tree is estimated at block 108. In some embodiments, the FFR value used is generated by comparing flow estimates through the original vascular tree model and the revascularized vascular tree model. FFR value calculations are described, for example, in International Publication No. WO 2014 / 111929, filed January 15, 2014. International Publication No. WO 2017 / 199245, filed March 16, 2017 (incorporated herein by reference in its entirety), describes color coding according to cumulative vascular resistance along each vascular branch, and in particular, displaying vascular resistance corresponding to FFR calculated based on features of vascular image data.

[0080] The operations of blocks 102-108 are not necessarily the only approach capable of providing mapped FFR values. For example, computational fluid dynamics (CFD) modeling of an appropriately reconstructed vascular model could potentially be used to cumulatively determine blood flow properties related to FFR along the extent of the vessel, e.g., to determine blood pressure at each point "as if" it had been measured directly, similar to how pressure sensor-based FFR is performed. In some embodiments, the method for calculating FFR impact scores can be applied to such alternative sources of FFR data. Accordingly, the flowchart of FIG. 1B begins with block 109, which simply receives FFR values ​​for the entire vascular tree.

[0081] In some embodiments (both FIGS. 1A and 1B), multiple estimated FFR values ​​are merged at block 110 to generate one or more FFR impact scores, for example, as described with respect to FIGS. 2A-2C.

[0082] Image-based FFR 2A-2C, which illustrate display results of a method for calculating FFR impact according to some embodiments of the present disclosure. The term "FFR impact score" is used herein to refer to a score that describes how the overall distribution of FFR values ​​within the vasculature, as distinct from the FFR measurements themselves, impacts a patient's clinical status. Patients with different FFR impact scores are potentially better candidates for different therapeutic interventions.

[0083] With specific reference first to Figure 2A, which illustrates a case containing moderate to severe ischemic vascular disease in three of five annotated vessels.

[0084] In some embodiments, the basis for the FFR impact score begins with individual FFR values ​​measured and / or calculated at locations along the vasculature to provide the FFR data of Figures 1A and / or 1B.

[0085] Image-based FFR calculation methods are described, for example, in International Publication No. WO 2014 / 111929, filed January 15, 2014. For example, in some embodiments, vascular geometries are determined for large portions of the vascular tree based on vascular imaging (e.g., 2D x-ray angiograms) and assessed for their potential to restore lost "reserve capacity," and an FFR value is calculated based on this assessment, for example, by calculating how vascular resistance would change if the current vascular state were restored to the calculated non-occluded geometry.

[0086] The image-based FFR index range is optionally the same as the pressure sensor-based FFR index, with values ​​ranging between 0 and 1. Optionally, 0.8 is maintained as a cutoff value (in some embodiments, a different cutoff value is used, e.g., 0.75 or 0.85), with values ​​above the cutoff value indicating that the lesion (if any), at least as such, is likely to be a non-ischemic lesion, and values ​​below 0.8 indicating that the lesion is likely to be an ischemic lesion.

[0087] In some embodiments, FFR values ​​are assigned throughout a three-dimensional model of the vasculature or other model (e.g., as shown in vascular tree 300 in FIG. 2A). For display purposes, in some embodiments, the three-dimensional model is optionally color-coded based on the FFR estimates at each of its locations (in FIG. 2A, scale bar 320 indicates the correspondence between FFR and gray levels). Optionally, individual FFR values ​​can be viewed, for example, by using a cursor to select specific locations on the coronary vascular tree model.

[0088] FFR impact scoring With continued reference to Figures 2A-2C, in some embodiments, further analysis includes converting the mapped FFR (e.g., as shown in a color-coded map of FFR along the vessel extent) into a measure that is easily understood by a physician in terms of the impact of the FFR on the clinical state of the vasculature, and in particular, its impact on how effective one or more potential treatment options may be in restoring vascular function (i.e., restoring a lost 'fractional flow reserve').

[0089] -Graphical FFR impact scoring Briefly referring now to FIG. 10, which is a schematic flowchart of a method for graphing received mapped FFR values ​​according to some embodiments of the present disclosure. In some embodiments, at block 1002, mapped FFR values ​​are received. In some embodiments, at block 1004, the FFR values ​​are converted into a cumulative graph, designated cumulative graph 1004A. Pie chart 330 (FIG. 2A) illustrates an example of cumulative graph 1004A, displaying mapped FFR in a manner that abstracts from vascular geometry in order to tease out patterns of vascular pathology indicated by the FFR data itself. FFR values ​​shown as distributed along the vessels in vascular tree 300 are instead sorted in descending order (values ​​closest to 1 being largest) and plotted as radii colored clockwise (grayscale) along a circle, with equal angular distances assigned to equal distances along the vessel extent. This combines data from all measured vessels (the five distal branches and their shared trunk segment) into a single overall vascular tree display.

[0090] Pie chart 330 allows for easy visual differentiation of the number of steps in FFR caused by the lesion. Four prominent post-lesion zones are distinguishable, beginning at angles 314, 315, 312, and 311, corresponding to four lesions located at vessel locations 302, 301, 308, and 304. A small lesion is also present along the vessel terminating at vessel location 310, and the corresponding FFR drop between angles 316 and 314 is highlighted by drawing a line to separate the small FFR drop between angles 316 and 314 from the 40% region with no drop between angles 313 and 316. In one instance where several lesions have more similar characteristics, two or more steps tend to merge into a single step. Between these zones, the light and dark steps are separated by relatively short (focal lesions) or long (dispersed lesions) transitions.

[0091] The number and sharpness of the steps are "derivative-related" in that they summarize information such as, for example, how many stents are required to completely revascularize the vascular tree, and whether this revascularization can be achieved by local correction of the vessel diameter.

[0092] The pie chart 330 provides information about the magnitude of the ischemic changes (FFR grayscale values ​​correspond to the numbers indicated by the scale bar 320) and how much of the entire vasculature is affected (corresponding to the "integral" information). The "40%" figure indicates how much of the vasculature is not affected, while an angle above 0.8, the nominal ischemia line (angle 314), indicates that nearly half of the entire vascular tree is experiencing ischemic blood flow.

[0093] As previously mentioned, vascular pathologies are somewhat blended by this representation. For example, the values ​​represented by angle 313 to angle 316 approximately span the only vascular range extending between vascular location 307 and each of vascular locations 308, 317, 304, and 302. Furthermore, the gradient in FFR is combined across multiple vessels and extends radially; for example, the values ​​contributed by the range between vascular locations 301 and 302 extend approximately between angle 314 and angle 311, blending with the values ​​contributed by the ranges between vascular locations 317 and 310, 308 and 309, and 304, 305, and 306. The range between vascular locations 301 and 303 (which is the range with the largest drop in FFR) corresponds approximately only to the region between angle 311 and angle 313.

[0094] These aspects of the visual pattern of the pie chart 330 may be understood to correspond, at least roughly, to disease severity, and in particular to disease severity indexed by appropriate treatment, for example, as discussed below.

[0095] Reference is now made to Figures 3A-3D, which schematically illustrate FFR impact scores (in the form of pie charts configured as previously described for pie chart 330) in relation to disease treatment options, according to some embodiments of the present disclosure. At a glance, it can be seen that the four cases presented span an ordered range of disease severity, from most severe in Figure 3A to healthiest in Figure 3D.

[0096] The conversion of these qualitative impressions into quantities will be explained after first briefly describing the nature of the currently available standard treatment options.

[0097] The currently commonly available treatment options for coronary artery disease can be divided into the following, in approximate order of increasing disease severity to which they are applied: [Table 1]

[0098] A typical criterion applied to distinguish between the three treatment options is to distinguish between single-, two-, and three-artery disease as markers for OMT, stenting, and CABG, respectively. However, this rule of thumb potentially results in misclassification of patients; for example, two-artery disease may actually be resistant to stenting, and three-artery disease may nevertheless be treatable with stenting. Similar misclassification is possible between single- and two-vessel disease. Physicians are aware of this and typically use multiple criteria in their decision-making. However, it is sometimes still unclear which treatment is appropriate for borderline patients. While numerous existing scoring methods, such as the SYNTAX score, can help address this issue, they also suffer from certain limitations, as discussed herein.

[0099] A score that preserves more of the nuance of the overall distribution of lesions in the vasculature, while still abstracting it enough to allow direct comparison of patterns (and therefore outcomes), offers potential benefits for optimal decision-making.

[0100] One aspect of the problem is determining whether repairing only a small number of lesions (ie, within the practical limits of stenting) will actually result in a sufficient improvement in coronary blood flow.

[0101] Numerical FFR impact scoring example The tabular summary 340 in Figure 2A shows the results of the tabular approach to generating the FFR impact score. Reference is also made to Figure 8, which is a schematic flow chart of the calculation of the FFR impact score components, according to some embodiments of the present disclosure.

[0102] In some embodiments, at block 802, a mapped FFR value is received.

[0103] In some embodiments, the score includes multiple components, several of which are calculated for each vessel, as indicated in the caption of boxed block 803, which surrounds blocks 804, 806, 808, and 810.

[0104] In some embodiments, a "total drop score" is selected at block 804 (represented as an output at block 804A). For each vessel marked in the modeled vascular tree, the maximum cumulative blood flow obstruction is selected (in the case of FIG. 2A, five values ​​result). As noted above, three vessel values ​​reach the hypervascularity score threshold of 0.8 (e.g., 1.0-0.20=0.8). Essentially, this measures the difference between the end of each marked vessel and a reference value representing a non-occluded vasculature location (the FFR at the beginning of the vascular tree, or simply 1, which is the maximum FFR by definition).

[0105] In some embodiments, a "Maximum Drop Score" (represented as an output in block 806A) is determined in block 806. The Maximum Drop Score indicates the percentage of the maximum drop due to a nominal "single focal lesion." For calculation purposes, the maximum size of a single focal lesion is, for example, 40 mm. 3 , or another maximum size, e.g., about 10 mm 3 and 100m 3 The size is chosen from the range of values ​​between

[0106] In some embodiments, block 810A represents the output of the lesion's diffuse severity (diffuse severity score). This is an indication that the overall vascular disease is increasingly diffuse along the described vessel, as the maximum drop score becomes increasingly smaller than the total drop score. In some embodiments, in block 808, the raw diffuseness score is calculated as the ratio between the total drop score and the maximum drop score, and is optionally normalized (e.g., by subtracting 1) so that a score of 0 indicates "maximally focal" lesion and higher values ​​indicate more diffuse lesion. In some embodiments, in block 810, a categorical ranking is optionally assigned to the lesion's diffuseness (e.g., none (no disease), focal (diffuse score less than, e.g., 0.1), moderate (diffuse score up to, e.g., 0.5), and severe (diffuse score greater than 0.5)). In some embodiments, diffusivity is scored by other methods, such as by lookup tables, non-linear functions, and / or machine learning results that link total and maximum FFR drop together to a database of patient outcomes.

[0107] In some embodiments, block 812A represents a 'vascularity score' output. In some embodiments, at block 812, a vascularity score is calculated.

[0108] In some embodiments, the hypervascularity score simply counts how many vessels have ischemic-level FFR values ​​anywhere along their length (under some limiting criterion, e.g., 0.8, or optionally a higher limiting criterion such as 0.9). In the example shown, the hypervascularity score is 3. Note that a common lesion, e.g., a lesion common to vessels 4 (terminating at vessel location 306) and 5 (terminating at vessel location 305), is counted only once and assigned to one of the two branches (vessel 4 in this case) for scoring purposes.

[0109] In some embodiments, the hypervascularity score 812A is based (in addition or alternatively) on a measure such as a "maximum drop score" 806A and is based on the number of blood vessels within a given volume (e.g., 40 3 mm or another volume, e.g., 20 mm 3 , 30m 3 , 50mm 3 , or 100mm 3 In some embodiments, this range includes vessels based on reaching at least a certain amount of drop in FFR value (within about 10 mm 3 and 100mm 3 The range of values ​​between 0.01 and 0.10 is selected from a range of values ​​between 0.01 and 0.10, which includes values ​​that potentially allow differentiation between lesions that are sufficiently focal to be good candidates for PCI treatment and lesions that are more diffuse and potentially less suitable for PCI treatment.

[0110] In the example of Figure 2A, two vessels have no unique lesions and one has "maximal focal disease." Vessel 1 (terminating at vessel location 303) has two lesions, the more severe of which accounts for more than half of the total drop. Vessel 2 appears to have only one distinct drop, but only accounts for approximately half of the total drop, indicating "severe" disease spread in this vessel. These factors, considered together, particularly given the finding of severe diffuse disease in one of the vessels, indicate that in some embodiments, CABG may be the preferred treatment for this patient, provided other risk factors permit.

[0111] Another example of an FFR impact score component is described herein in connection with FIG.

[0112] Figures 2B and 2C provide examples of different vascular conditions (as assessed by FFR) and their associated FFR impact scores.

[0113] In Figure 2B (vascular tree 342, pie chart 341, and tabular summary 343), the largest portion of pie chart 341 (labeled 69%) has FFR values ​​well below 1, but still hovering above the pressure sensor-based FFR cutoff of 0.80. Nonetheless, this is "three-vessel disease" according to the more stringent FFR criteria (using the 0.9 FFR criterion as the cutoff, resulting in a multivessel score of 3). Therefore, the severity of this disease appears more suitable for stenting (since all lesions are focal or moderately diffuse). Depending on the risk factors associated with PCI, which are presented as opposing (since all lesions are above the 0.80 cutoff), the option of continuing with OMT may also be available.

[0114] 2C (vascular tree 352, pie chart 351, and tabular summary 353), all vessels are diseased to some extent, but only two pass the total drop FFR cutoff of 0.9, indicating a level of diffusion that is focal, or at worst, moderate. This subject would therefore, in some embodiments, be placed on OMT rather than undergo PCI, which would otherwise be the baseline treatment of choice for the two-vessel disease state.

[0115] It should be understood that the present invention is not limited to using a pie chart to graphically represent values, for example, the values ​​of pie chart 341. In some embodiments, the graph is a Cartesian graph of the values ​​(e.g., FFR value counts on the x-axis and FFR values ​​on the y-axis distance), a polar plot of the values ​​(e.g., FFR value counts on the angle axis and FFR values ​​on the radial length), or another graphing method.

[0116] Additional examples of numerical FFR impact scoring Reference is now made to FIG. 4, which illustrates a display result of a method for calculating FFR impact according to some embodiments of the present disclosure.

[0117] Displayed again are vascular tree 404, pie chart 402, and tabular summary 401, which generally correspond to vascular tree 300, pie chart 320, and tabular summary 340 of Figure 2A. The labels in vascular tree 404 add severity and diffuse outcome values ​​(along with categorical ratings) that correspond to the values ​​also shown in tabular summary 401.

[0118] In this example, "TFS" is used as an abbreviation for "Total FFR Score," which is used equivalently to the term "FFR Impact Score."

[0119] The scores of "Total Severity TFS," "Maximum Severity TFS," "Diffuse TFS," and "Hypervascular TFS" in Figure 4 correspond to the "Total Drop" score, "Maximum Drop" score, and "Diffuse" score in Figure 2A.

[0120] In Figure 4, the "Severity FFR" score for the entire vascular tree is shown, calculated by calculating the average FFR value for all locations in the vascular tree, with downward weighting depending on the distance of each location from the ostium. A value of 1 is completely non-occlusive. The downward weighting depending on the distance from the ostium gives greater importance to lesions closer to the base of the vascular tree (and therefore their impact is greater).

[0121] Reference is now made to FIG. 9, which illustrates a schematic diagram of how the mean severity score is calculated, according to some embodiments of the present disclosure.

[0122] In some embodiments, mapped FFR values ​​are received at block 902. In some embodiments, the values ​​are weighted by distance (increasing distances are weighted downwards) at block 904. In some embodiments, a severity score is calculated at block 906 by averaging the FFR values ​​according to their weights. Block 906A represents the resulting severity score (as a weighted average).

[0123] Also shown in Figure 4 is a bar graph 403 showing FFR per volume. Essentially, the length of the bar is weighted by volume, not simply distance along the vessel centerline. This method again gives somewhat less weight to vessel regions further downstream (within narrower vessel segments). This has the potential advantage of corresponding to how much area is ultimately perfused by blood flowing through a particular portion of the vessel, and thus the size of the area directly affected by ischemic blood flow at that segment.

[0124] Continuing with reference to Figure 10, mapped FFR values ​​are received at block 1002. The vessel volume associated with each mapped FFR value within a given vessel location is used to graph the mapped FFR values ​​as volume-weighted values ​​at block 1006. Block 1006A represents the volume-weighted graph obtained at block 1006.

[0125] In some embodiments, FFR-based subscores are provided for "left main stenosis," where stenoses within the left main coronary artery are specifically selected for attention by metrics such as "total drop" or "maximum drop" calculations made for individual vessel branches.

[0126] In some embodiments, patterns in the mapped FFR values ​​are associated with certain additional features, which are optionally indicated in the FFR impact score. For example:

[0127] Lesion length The length of a vascular lesion throughout which the mapped FFR is decreased contiguously and significantly. For this metric, "significantly" means, for example, a decrease of more than a given threshold (e.g., about 0.1) over the entire length. "Continuously" means without interruption, or, optionally, a decrease of less than a certain vessel distance or volume threshold (e.g., 10 mm). 3 , 20mm 3 , 30mm 3 , or 40mm 3 (smaller than 10 mm) and have only a certain minimum tilt magnitude, e.g. 3 , 20mm 3 , 30mm 3 , or 40mm 3 A hit means a decrease with a minimum slope magnitude of at least 0.1.

[0128] Main vessel + side branch disease Extending from the main vessel, past the vessel bifurcation point, to the branch vessels, there is a significant decrease in the mapped FFR throughout (e.g., a given threshold (e.g., about 0.1, optionally a specific vessel length and / or volume (e.g., 40 mm 3 , or another volume, e.g., about 10 mm 3 and 100mm 3 The volume is chosen from the range of values ​​between 0 and 1, and is normalized to the vascular area.

[0129] Bifurcated / trifurcated lesions Extending over three or more vessel segments (e.g., a main vessel and two side vessels beyond a vessel branch), where the mapped FFR is significantly reduced throughout (e.g., above a given threshold (e.g., about 0.1, optionally within a specific vessel length and / or volume (e.g., 40 mm 3 , or another volume, e.g., about 10 mm 3 and 100mm 3 The volume is chosen from the range of values ​​between 0 and 1, and is normalized to the vascular area.

[0130] Aortic ostial lesions The aorta and / or the aortic ostium itself is significantly reduced, for example, by about 0.1 (optionally, a specific vessel length and / or volume (40 mm 3 , or another volume, e.g., about 10 mm 3 and 100mm 3 The region of the mapped FFR that is super-decreased (e.g., normalized to a volume selected from the range of values ​​between

[0131] degree of curvature One measure of tortuosity is that a vessel segment exhibits excessive curvature such that the ratio of the distance along the vessel segment to the smallest distance between the two endpoints of the curved vessel segment is high. For example, a tortuous vessel has a ratio of 1.3 or greater. In some embodiments, the FFR impact score indicates the presence of tortuosity associated with a vessel region throughout which the mapped FFR is significantly and continuously reduced. "Significantly" in some embodiments means a reduction of more than a given threshold (e.g., about 0.1) over the entire length. Optionally, the reduction is significant over a particular vessel length and / or volume (e.g., 40 mm 3 , or another volume, e.g., about 10 mm 3 and 100mm 3 The normalization is performed for the volume (e.g., volume chosen from the range of values ​​between

[0132] Number of stents / estimated stent effectiveness For example, any combination of the FFR impact score features described above and / or those described in connection with Figures 2A-2C can be used to generate a stent number estimate. For example, lesion length and complexity can be evaluated to determine the appropriate number of stents that would restore flow function to a certain degree of improvement (e.g., to an FFR of 0.85, 0.90, 0.95, or 1.0). Optionally or alternatively, the maximum number of stents can be constrained, for example, based on an estimate of the procedural risk and / or feasibility, and the resulting stent number estimate (e.g., potentially limited to a maximum value due to risk) along with an estimate of the degree of improvement that may result.

[0133] CABG number / CABG effectiveness estimate For example, any combination of the FFR impact score features described above and / or those described in connection with Figures 2A-2C can be used to generate a graft number estimate. For example, lesion length and complexity can be assessed to determine the appropriate number of grafts that would restore blood flow function to some degree of improvement (e.g., to an FFR of 0.85, 0.90, 0.95, or 1.0). Optionally or alternatively, the maximum number of grafts can be constrained, for example, based on an estimate of the risk and / or feasibility of the procedure, and the resulting graft number estimate (e.g., potentially limited to a maximum value due to risk) along with an estimate of the degree of improvement that may result.

[0134] -Fixed FFR impact scoring In some embodiments, the system configured to calculate the FFR impact score is also configured to recalculate the FFR impact score using data describing measured and / or simulated changes in vascular conditions, e.g., post-stent angiography images, and / or changes in the vascular tree model that simulate changes in disease conditions (e.g., obtained as a result of treatment and / or disease progression).

[0135] The FFR impact score (e.g., any of the numerical, graphical, and / or tabular data shown in one of Figures 2A-2C and / or 4) is updated based on one or more of the following:

[0136] Automated Virtual Stenting: Vessel diameters at proximal and / or distal vessel locations are used as criteria for what constitutes the expected revascularized ('restored healthy') diameter after virtual stenting. The revascularized diameters are used to adjust the vascular tree model used to obtain new FFR data, and the FFR impact score is recalculated accordingly. In some embodiments, options are displayed according to an appropriately weighted blend of criteria that result in the greatest improvement and the least intervention.

[0137] Manual stent selection: according to the provided stent parameters, e.g., position, length, and diameter, the vascular tree model is adjusted to obtain adjusted FFR data and the FFR impact score is recalculated accordingly. Optionally, the available stent parameters are constrained to known and / or available stent(s), e.g., to stents available in the current inventory.

[0138] Post-PCI data: Post-stent angiography images are used to adjust the vascular tree model. Adjusted FFR data is obtained and the FFR impact score is recalculated accordingly. 1. Follow-up: Angiographic image data acquired from a patient over the course of multiple diagnostic procedures (e.g., performed over a period of weeks, months, or years) is converted into multiple time-dependent vascular tree models. Adjusted FFR data is obtained for each model, and the FFR impact score is recalculated accordingly, resulting in an output describing the change in the FFR impact score over the period spanned by the image monitoring. In some embodiments, a comparison of two or more FFR impact scores derived from FFR data obtained over the course of multiple diagnostic procedures is used to estimate the rate of progression of the vascular disease. In some embodiments, the rate of progression of the vascular disease is used to schedule further diagnostic procedures. Optionally, the comparison is performed on FFR impact scores calculated considering only vessel segments that are commonly scored in all calculated FFR impact scores.

[0139] - System component implementation example Reference is now made to FIG. 6, which schematically illustrates a system 600 for calculation of an FFR impact score, according to some embodiments of the present disclosure.

[0140] Data storage 604, in some embodiments, stores FFR data (e.g., in any of the forms described herein as computer-readable medium and / or memory. Optionally, data storage 604 is used to store images used in calculating FFR, for example, according to the method outlined in FIG. 1A.

[0141] The processing unit 608, in some embodiments, performs processing to convert the FFR data into an FFR impact score, for example, according to any one or more of the calculations used to calculate the FFR impact score components described herein (e.g., in connection with Figures 2A-2C and / or Figure 4).

[0142] The user interface 602, in some embodiments, accepts user input (e.g., to select and / or define data for calculations and / or to provide commands to initiate and / or configure processes). In some embodiments, the user interface 602 also displays FFR impact score information, for example, in formats such as those illustrated and / or described herein with respect to Figures 2A-4. Optionally, the system of Figure 6 is also a system for angiographic image analysis more generally, such as the system described with respect to Figure 5.

[0143] Reference is now made to FIG. 7, which schematically illustrates the data and processing instruction components of a system 600 for calculation of an FFR impact score, according to some embodiments of the present disclosure.

[0144] The mapped FFR data 702 includes FFR data calculated and stored in the data storage device 604, for example, as described in connection with FIGS. 1A-1B.

[0145] The processing instruction component, in some embodiments, includes computer code, for example, stored in storage device 604 and processed by processing unit 608. A portion of the processing instruction component includes FFR impact subscore calculation code 704, which in some embodiments performs one or more of the subscore calculations, for example, as described in connection with Figures 2A-2C and / or 4. In some embodiments, the processing instruction component also includes an FFR impact score display module, for example, an FFR impact score display module configured to convert the subscore calculations of impact subscore calculation code 704 into a display, for example, as described in connection with Figures 2A-4.

[0146] Reference is now made to FIG. 5, which illustrates an example of a screen output provided by a system 600 adaptable for calculating and displaying a total FFR score, according to some embodiments of the present disclosure.

[0147] In some embodiments, system 600 is a non-invasive, image-based software device that provides physicians with quantitative analysis of the functional significance of coronary lesions, similar to invasive FFR, and qualitative three-dimensional models of illustrated coronary arteries during routine PCI procedures. For example, summary block 506 shows an FFR of 0.66 for a selected flow-restricted vessel 501B in three-dimensional coronary artery model 501, with the color of flow-restricted vessel 501B matching the shading of color bar 502 in 501C. A centerline vessel tree 504 is also shown, corresponding to three-dimensional coronary artery model 501, and superimposed on an x-ray angiogram 503. The diameter of flow-restricted vessel 501B is plotted along graph 505, which includes a dip at location 505B corresponding to the location of flow restriction that primarily contributes to the FFR of flow-restricted vessel 501B decreasing from a perfectly healthy value of 1.00 to its designated value of 0.66.

[0148] System 600, in some embodiments, performs processing and calculations based on angiographic images and hemodynamic information acquired during coronary catheterization.

[0149] Optionally, system 600 does not require the use of additional invasive devices or vasodilatory therapy. Potential advantages and / or features of system 600 related to FFR-guided PCI decision-making include, in some embodiments: Intraoperative imaging delivery, computation, and 3D multi-vessel modeling for stenosis quantification, PCI decision optimization, and end-of-case revascularization confirmation. Objective FFR measurement without the risks associated with invasive FFR wires, including additional interventions and pharmacological administration. Use of existing cath lab imaging and angiography equipment, compatible with major angiography systems. Elimination of direct and indirect FFR wire costs without introducing additional SKUs or device-related procedural costs.

[0150] The reconstructed three-dimensional model provided by the system 600 describes the shape and volume of the vessel and, together with hemodynamic parameters, serves as the basis for blood flow analysis. Based on the blood flow analysis, an FFR can be calculated for the inspected vessel. In some embodiments, the blood flow calculation is based on a centralized model of the artery, which allows for shorter processing times for delivering FFR results to the physician during the PCI procedure. After calculation, the system 600 presents a three-dimensional simulation of the vascular tree and the calculated FFR value for the vessel of interest, as shown in FIG. 5.

[0151] In some embodiments, a total FFR score, such as that described in connection with FIGS. 1A-4, is calculated based on information provided by a suitably configured system 600, particularly based on FFR calculations for individual vessels and / or locations along individual vessels.

[0152] (General matters) The term "about" as used herein in reference to amounts and numerical values ​​means "within a range of ±10% of (about)."

[0153] The words "comprises," "comprising," "includes," "including," "having," and their conjugations mean "including, but not limited to."

[0154] The term "consisting of" means "including and limited to."

[0155] The term "consisting essentially of" means that a composition, method, or structure may include additional ingredients, steps, and / or parts so long as the additional ingredients, steps, and / or parts do not materially alter the basic and novel characteristics of the claimed composition, method, or structure.

[0156] As used herein, the singular includes plural reference unless the context clearly dictates otherwise. For example, the term "a compound" or "at least one compound" may include a plurality of compounds, including mixtures thereof.

[0157] The words "example" and "exemplary" are used herein to mean "serving as an example, instance, or illustration." Any embodiment described as "example" or "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments and / or to exclude the incorporation of features from other embodiments.

[0158] The word "optionally" is used herein to mean "provided in some embodiments and not provided in other embodiments." Any particular embodiment of the present disclosure may include multiple "optional" features unless such features contradict each other.

[0159] As used herein, the term "method" refers to methods, means, techniques, and procedures for achieving a given purpose, including, but not limited to, methods, means, techniques, and procedures that are known or that can be readily developed from known methods, means, techniques, and procedures by those skilled in the art of chemistry, pharmacology, biology, biochemistry, and medicine.

[0160] As used herein, the term "treating" includes terminating, substantially inhibiting, slowing, or reversing the progression of a condition, substantially ameliorating the clinical or cosmetic symptoms of a condition, or substantially preventing the onset of clinical or cosmetic symptoms of a condition.

[0161] Throughout this application, embodiments may be presented with reference to a range format. Descriptions in range format are merely for convenience and simplicity and should not be construed as rigid limitations on the scope of the descriptions of the present disclosure. Accordingly, descriptions of ranges should be construed as specifically disclosing all possible subranges as well as individual numerical values ​​within that range. For example, descriptions of ranges such as "1 to 6" should be construed as specifically disclosing subranges such as "1 to 3," "1 to 4," "1 to 5," "2 to 4," "2 to 6," "3 to 6," etc., as well as individual numerical values ​​within that range, e.g., 1, 2, 3, 4, 5, and 6.

[0162] Whenever a numerical range (e.g., "10-15," "10 to 15," or any pair of numbers connected by another such range expression) is given herein, it is intended to include any number (non-integer or integer) within the stated range threshold (inclusive), unless the context clearly dictates otherwise. The phrase "range between" a first and second stated value and the phrase "range" from a first stated value "of" or "to" a second stated value (or another such range expression term) are used interchangeably herein and are intended to include the first and second stated values ​​and all non-integer and integer values ​​therebetween.

[0163] While the description of this disclosure has been provided in conjunction with specific embodiments, it will be apparent to those skilled in the art that many alternatives, modifications, and variations are possible. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the invention as defined by the appended claims.

[0164] It will be apparent that certain features that are, for clarity, described in the context of separate embodiments in this disclosure may also be provided in combination in a single embodiment. Conversely, various features that are, for brevity, described in the context of a single embodiment may also be provided separately or in any suitable subcombination, or in any other described embodiment of this disclosure. Certain features described in the context of various embodiments should not be construed as essential features of those embodiments, unless those embodiments cannot function without those elements.

[0165] The entire contents of all publications, patents, and patent applications mentioned in this specification are incorporated herein by reference to the same extent as if each individual publication, patent, and patent application was specifically and individually indicated to be incorporated herein by reference. Furthermore, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present disclosure. To the extent that section headings are used, they should not be construed as necessarily limiting. Additionally, the entire contents of the priority documents of this application are incorporated herein by reference.

[0166] [Note] [Appendix 1] 1. A method for estimating a clinical state of a vascular segment, comprising: receiving a fractional flow reserve (FFR) map that assigns a plurality of FFR values ​​to specific locations on each of a plurality of vascular segments of a vascular tree representing the vascular portion; and calculating an FFR impact score using the mapped FFR values, a component of the FFR impact score discarding the mapping of FFR values ​​to the particular location; A method comprising:

[0167] [Appendix 2] the map of FFR assigns FFR values ​​to the specific locations in a continuous or near-continuous manner; The method described in Appendix 1.

[0168] [Appendix 3] the map of FFR includes at least five FFR values ​​for each of at least four vessel segments; 3. The method according to claim 1 or 2.

[0169] [Appendix 4] the map of FFR represents a contribution to the reduction in blood flow potential from upstream locations common to each of the identified locations. 3. The method according to claim 1 or 2.

[0170] [Appendix 5] the vascular tree models a plurality of vascular regions of the vascular segment connected at branching points; Each of the vessel segments comprises: the origin of the vascular tree, First vascular branching point A second vessel branch point, or Disconnected ends of the vascular tree stretching between two of 5. The method of any one of appendices 1 to 4.

[0171] [Appendix 6] the FFR impact score includes a plurality of score elements, each of which discards the mapping of an FFR value to the particular location but retains its association with a particular one of the plurality of vessel segments. 5. The method of any one of appendices 1 to 4.

[0172] [Appendix 7] the plurality of score elements includes a total drop score for each of the plurality of vessel segments, the total drop score representing a total drop in FFR along the vessel segment from a baseline value representing non-occluded vasculature; The method described in Appendix 6.

[0173] [Appendix 8] assigning an occluded or non-occluded status to each of the plurality of vessel segments based at least on the total drop score for that segment; Counting the number of occluded vessel segments; and Providing the total number as a hypervascular score, which is a score element of the FFR impact score; Further comprising: 8. The method according to claim 6 or 7.

[0174] [Appendix 9] the plurality of score elements include, for each of the plurality of vessel segments, a maximum drop score representing a maximum drop in FFR along the vessel segment along a defined portion of the vessel segment that is shorter than the entire vessel segment; 9. The method of any one of appendices 6 to 8.

[0175] [Appendix 10] The defined portion is about 10 mm 3 and about 100 mm 3 is the distance within which the blood volume falls within the range between The method described in Appendix 9.

[0176] [Appendix 11] The defined portion is about 40 mm 3 is the distance that can accommodate the blood volume of 11. The method described in Appendix 10.

[0177] [Appendix 12] assigning an occluded or non-occluded status to each of the plurality of vessel segments based on at least the maximum drop score for that segment; Counting the number of occluded vessel segments; and Providing the total number as a hypervascular score, which is a score element of the FFR impact score; Further comprising: 11. The method according to claim 9 or 10.

[0178] [Appendix 13] the plurality of score elements include, for each of the plurality of vessel segments, a diffusivity score that represents a measure of how widely distributed along that vessel segment are lesions that contribute to a total drop in FFR. 13. The method of any one of appendices 6 to 12.

[0179] [Appendix 14] calculating a vascular drop diffusivity score includes determining the extent to which the maximum drop score differs from the total drop score; The method described in Appendix 13.

[0180] [Appendix 15] Calculating the vascular drop diffusivity score includes calculating a ratio of the total drop score to the maximum drop score. The method described in Appendix 14.

[0181] [Appendix 16] the plurality of score elements includes a severity score representing a weighted average of FFR at all locations within the vascular tree, with locations at greater distances from the origin of the vascular tree being weighted downward; 16. The method of any one of appendices 6 to 15.

[0182] [Appendix 17] the plurality of score elements includes one or more score elements associated with a segment including the left main coronary artery up to a first bifurcation point of the left main coronary artery represented in the vascular tree; 17. The method of any one of appendixes 6 to 16.

[0183] [Appendix 18] the FFR impact score includes a sorted value chart score element representing the FFR values ​​of each of the plurality of vessel segments in a composite value sort order such that values ​​from different vessel segments are interleaved with each other. 17. The method of any one of appendixes 1 to 16.

[0184] [Appendix 19] displaying the sorted value chart score elements as a color-coded pie chart; 18. The method described in Appendix 18.

[0185] [Appendix 20] the FFR impact score includes histogram chart score elements representing the FFR values ​​of each of the plurality of vessel segments in a composite histogram, the contribution of each FFR value to the histogram being weighted according to the size of the vessel volume within which that FFR value occurs. 20. The method of any one of appendices 1 to 19.

[0186] [Appendix 21] The FFR impact score includes a score component that describes lesion length based on the distance over which FFR values ​​continuously decrease. 21. The method of any one of appendices 1 to 20.

[0187] [Appendix 22] The FFR impact score is: including both the main vessel and side branches; including a main blood vessel and at least two of its branches; those occurring within the aortic ostial vessel segment; occurring adjacent to a tortuous region of the vasculature; or those occurring within tortuous regions of the vascular system; a score element that describes the lesion geometry as one or more of: 22. The method of any one of appendices 1 to 21.

[0188] [Appendix 23] Automated virtual stenting, manual stent selection, Data measured after stent placement, or Data measured through multiple diagnostic procedures, adjusting the FFR impact score based on a modified map of FFRs modified according to one or more of: 23. The method of any one of appendices 1 to 22.

[0189] [Appendix 24] comparing the FFR impact score to a second FFR impact score calculated according to the method described in Appendix 1; and Estimating the rate of progression of vascular disease; Including, 24. The method of any one of appendices 1 to 23.

[0190] [Appendix 25] scheduling further diagnostic procedures based on said estimation. The method described in Appendix 24.

[0191] [Appendix 26] and planning a treatment procedure based on the FFR impact score. 26. The method of any one of appendices 1 to 25.

[0192] [Appendix 27] selecting between OMT and PCI based on the FFR impact score; 26. The method described in Appendix 26.

[0193] [Appendix 28] selecting between PCI and CABG treatment based on the FFR impact score; 28. The method according to claim 26 or 27.

[0194] [Appendix 29] and planning at least one of the number, location, and / or type of stents to be placed based on the FFR impact score. 29. The method of any one of appendices 26 to 28.

[0195] [Appendix 30] and planning at least one of the number and / or location of CABG grafts to be placed based on the FFR impact score. 29. The method according to claim 26 or 28.

[0196] [Appendix 31] 1. A method for estimating a clinical state of a vascular segment, comprising: receiving a fractional flow reserve (FFR) map that assigns a plurality of FFR values ​​to specific locations on each of a plurality of vascular segments of a vascular tree representing the vascular portion; and calculating an FFR impact score using the mapped FFR values, the FFR impact score including a component comparing a total drop in FFR along at least one of the vessel segments to a maximum drop in FFR along that vessel segment; A method comprising:

[0197] [Appendix 32] 1. A method for estimating a clinical state of a vascular segment, comprising: receiving a fractional flow reserve (FFR) map that assigns a plurality of FFR values ​​to specific locations on each of a plurality of vascular segments of a vascular tree representing the vascular portion; and calculating an FFR impact score using the mapped FFR values, the FFR impact score comprising a graph combining the individual FFR values ​​from the plurality of vessel segments into a display in which at least some of the individual FFR values ​​are shown in positions on the graph that are not adjacent to any other FFR values ​​obtained from adjacent vessel locations; A method comprising:

[0198] [Appendix 33] 10. A system including a processor configured to perform the method described in claim 1.

[0199] [Appendix 34] 1. An apparatus for estimating a clinical state of a vascular segment, comprising: a data storage device that stores a data structure that assigns a plurality of fractional flow reserve (FFR) values ​​to specific locations on each of a plurality of vascular segments of a vascular tree representing the vascular portion; and communicatively connected to the data storage device; and calculating an FFR impact score using the assigned FFR values; using a component of the FFR impact score to discard the assignment of the FFR value to the particular location; displaying the FFR impact score in a user interface; a processing device configured to An apparatus comprising:

[0200] [Appendix 35] the FFR impact score includes a plurality of score elements, each of which discards the assignment of an FFR value to the particular location but retains its association with a particular one of the plurality of vessel segments. 35. The apparatus of claim 34.

[0201] [Appendix 36] the plurality of score elements includes a total drop score for each of the plurality of vessel segments, the total drop score representing a total drop in FFR along the vessel segment from a baseline value representing non-occluded vasculature; 36. The apparatus of claim 35.

[0202] [Appendix 37] The processing device includes: assigning an occluded or non-occluded status to each of the plurality of vessel segments based at least on a total drop score for that segment; Counting the number of occluded vessel segments; and The total number is used as the hypervascularity score, which is a score element of the FFR impact score. It is configured as follows: 37. The apparatus of claim 35 or 36.

[0203] [Appendix 38] the FFR impact score includes a sorted value chart score element representing the FFR values ​​of each of the plurality of vessel segments in a composite value sort order such that values ​​from different vessel segments are interleaved with each other. 38. The apparatus of any one of clauses 34 to 37.

[0204] [Appendix 39] the processing unit is configured to cause the user interface to display the sorted value chart score elements as a color-coded pie chart. 39. The apparatus of claim 38.

[0205] [Appendix 40] the FFR impact score includes histogram chart score elements representing the FFR values ​​of each of the plurality of vessel segments in a composite histogram, the contribution of each FFR value to the histogram being weighted according to the size of the vessel volume within which that FFR value occurs. 40. The apparatus of any one of clauses 34 to 39.

[0206] [Appendix 41] the processing unit is configured to cause the user interface to display the histogram chart score elements. 41. The apparatus of claim 40.

[0207] [Appendix 42] Automated virtual stenting, manual stent selection, Data measured after stent placement, or Data measured through multiple diagnostic procedures, and adjusting the FFR impact score based on a revised allocation of FFRs according to one or more of: 42. The apparatus of any one of clauses 34 to 41.

[0208] [Appendix 43] the processing unit is configured to compare the FFR impact score to a second FFR impact score and estimate a rate of progression of vascular disease based on the comparison. 42. The apparatus of any one of clauses 34 to 41.

Claims

1. 1. A method for estimating a clinical state of a vascular segment, comprising: receiving a fractional flow reserve (FFR) map that assigns a plurality of FFR values ​​to specific locations on each of a plurality of vascular segments of a vascular tree representing the vascular portion; using the mapped FFR values ​​to calculate a first FFR impact score indicative of the overall impact of occlusive vascular disease in the vascular tree; updating the mapped FFR values ​​and the map of FFR based on data describing measured and / or simulated changes in vascular conditions; and using the updated mapped FFR values ​​to calculate a second FFR impact score indicative of the overall impact of occlusive vascular disease in the vascular tree; A method comprising:

2. The data describing the measured and / or simulated changes in vascular status are based on geometric changes to the vascular tree. The method of claim 1.

3. The data describing the measured and / or simulated changes in vascular condition are determined by automated virtual stenting.

3. The method according to claim 1 or 2.

4. The data describing the measured and / or simulated changes in vascular condition are based on values ​​of vascular diameter at proximal and / or distal vascular locations on each of the plurality of vascular segments. The method of claim 3.

5. The data describing the measured and / or simulated changes in vascular condition are determined based on one or more stent parameters.

3. The method according to claim 1 or 2.

6. The method of claim 1, wherein the one or more stent parameters include one or more of a vessel position, a stent length, and a stent diameter. The method of claim 5.

7. The one or more stent parameters are provided by user input.

7. The method according to claim 5 or 6.

8. The data describing the measured and / or simulated changes in vascular status include post-PCI data.

3. The method according to claim 1 or 2.

9. The method of claim 8, wherein the data describing the measured and / or simulated changes in vascular status includes image data derived from one or more angiographic images obtained from the patient.

10. The method of claim 1, 2, or 8.

10. The data describing the measured and / or simulated changes in vascular condition are measured after stent placement.

10. The method of claim 1, 2, 3, 8, or 9.

11. The second FFR impact score includes a sorted value chart score element that represents the updated FFR values ​​of each of the multiple vascular segments of the updated FFR map in a composite value sort order such that values ​​from different vascular segments of the updated vascular tree model are interleaved with each other.

11. The method according to any one of claims 1 to 10.

12. Further comprising displaying the second FFR impact score. The method of claim 11.

13. The method of claim 12, further comprising comparing the first FFR impact score with the second FFR impact score and estimating a rate of progression of vascular disease.

13. The method of any one of claims 1 to 12.

14. A system including a processor configured to execute the method of claim 1.

15. An apparatus for estimating a clinical state of a vascular segment, comprising: a data storage device that stores a data structure that assigns a plurality of fractional flow reserve (FFR) values ​​to specific locations on each of a plurality of vessel segments of a vascular tree representing the vascular portion; and communicatively connected to the data storage device; and using the assigned FFR values ​​to calculate a first FFR impact score indicative of the overall impact of occlusive vascular disease in the vascular tree; updating the assigned FFR value based on data describing changes in measured and / or simulated vascular conditions; and using the updated assigned FFR values ​​to calculate a second FFR impact score indicative of the overall impact of occlusive vascular disease in the vascular tree. a processing device configured to Including, Device.

16. The method of claim 15, further comprising: a user interface; and wherein the processing device is configured to cause the user interface to display the first FFR impact score and / or the second FFR impact score.

16. The apparatus of claim 15.

17. The data describing the measured and / or simulated changes in vascular status include: Automated virtual stenting, Manual stent selection, or Post-PCI data, Based on one or more of the following:

17. Apparatus according to claim 15 or 16.

18. The processing device is configured to compare the first FFR impact score with the second FFR impact score, and estimate a rate of progression of vascular disease based on the comparison.

18. Apparatus according to any one of claims 15 to 17.

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