Mapping regional activation times during sinus and non-sinus rhythm cardiac cycles

Abstract

To provide a method of mapping local activation times for sinus rhythm and non-sinus rhythm cardiac cycles.SOLUTION: Each of sets of signals received during multiple cardiac cycles indicates, for a probe inserted into a cardiac chamber, a 3D location of a distal end of the probe, electrical potentials measured at the location, and respective times during a cycle when the electrical potentials were measured. The measurements and the times are compared to a first template for a sinus rhythm cardiac cycle and a second template for a non-sinus rhythm cardiac cycle so as to identify cardiac cycles including consecutive first, second and third cardiac cycles. The first and second cardiac cycles are in accordance with the first template, and the third cardiac cycle matches the second template. A physical map is generated based on the locations. Based on the received locations and corresponding electrical potentials, an electroanatomic map comprising the local activation times for the non-sinus rhythm cardiac cycle overlaid on the physical map is rendered to a display.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] The present invention relates generally to cardiac mapping, and more particularly to mapping regional activation times during sinus rhythm and non-sinus rhythm cardiac cycles. [Background technology]

[0002] Cardiac arrhythmias, such as atrial fibrillation, are heart rhythms that result in irregular heartbeats. Arrhythmias typically occur when areas of cardiac tissue disrupt the normal cardiac cycle by abnormally conducting electrical signals to adjacent tissue, causing an asynchronous rhythm.

[0003] Mapping electrical potentials within the heart is a commonly used tool for diagnosing and treating cardiac arrhythmias. Typically, time-varying electrical potentials within the endocardium are sensed and recorded as a function of location within the heart, and then used to map regional electrograms or regional activation times. Activation times vary from point to point within the endocardium due to the time it takes for an electrical impulse to conduct through the myocardium. The direction of this electrical conduction at any point within the heart is conventionally represented by an activation vector perpendicular to the isoelectric activation front, either of which may be derived from a map of activation times. The propagation velocity of the activation front through any point on the endocardium may be represented as a velocity vector.

[0004] Mapping the activation surface and conduction fields assists physicians in identifying and diagnosing abnormalities such as ventricular and atrial tachycardias and ventricular and atrial fibrillation, which result from areas of impaired electrical propagation within cardiac tissue.

[0005] U.S. Patent Application Publication No. 2015 / 0073246 to Chimel et al. describes a method for manually mapping premature ventricular contractions (PVCs). The method involves recording a series of electrocardiogram (ECG) signals from a patient suffering from PVCs, followed by selection by a physician of beats indicative of sinus rhythm and beats indicative of PVCs. The sinus beats are used to generate a physical map of the heart. Electrophysiological measurements of local activation time (LAT) obtained during PVC beats are then overlaid on the sinus map to generate a so-called LAT hybrid map.

[0006] U.S. Patent No. 5,271,411 to Ripley et al. describes a method for ECG signal analysis and cardiac arrhythmia detection that includes identifying normal QRS complexes and labeling the QRS complexes acquired after identifying the normal QRS complexes based on a number of rules and their respective locations.

[0007] U.S. Patent No. 4,336,810 to Anderson et al. describes a method for arrhythmia analysis of ECG recordings. The method involves receiving ECG signals and comparing them to known templates based on previously identified group classifications. Based on this comparison, each of the received signals can be designated as normal, ventricular ectopic, supraventricular ectopic, or unknown (ectopic activation of unknown origin).

[0008] U.S. Patent Application Publication No. 2012 / 0165895 to Dong et al. describes a method for non-captured intrinsic discrimination in cardiac pacing response classification. The method includes discriminating non-captured intrinsic beats during detection and classification of evoked responses by comparing features of a post-paced cardiac signal to expected features associated with non-captured responses with intrinsic activation. In some embodiments, detection of non-captured responses with intrinsic activation may be based on peak amplitude and timing of the cardiac signal.

[0009] Thiagalingam et al., U.S. Patent Application Publication No. 2009 / 0099468, describes a method for automated processing of electrophysiological data. The method includes determining a temporal location by defining one or more reference channels containing a reference beat and comparing a beat of recorded electrogram data to the defined one or more reference channels. An indication of the temporal location and other information of the beat in the recorded electrogram data is generated, and the indication of the temporal location can be used to analyze the recorded electrogram data to identify electrophysiological features indicative of an abnormality. Summary of the Invention [Means for solving the problem]

[0010] According to an embodiment of the invention, a method is provided that includes receiving, by a processor, a set of signals during a plurality of cardiac cycles, each set of signals indicating, for a medical probe inserted into a cardiac ventricle, a three-dimensional (3D) position of a distal end of the probe, electrical potentials measured at the 3D position, and a respective time during a given cardiac cycle when the electrical potentials were measured; comparing the received electrical potential measurements and respective times to a first template for sinus rhythm cardiac cycles and a second template for non-sinus rhythm cardiac cycles to identify a series of cardiac cycles including consecutive first, second, and third cardiac cycles, wherein the first and second cardiac cycles follow the first template and the third cardiac cycle follows the second template; generating a physical map of the cardiac ventricle based on the 3D positions; and rendering on a display an electroanatomical map including regional activation arrival times of the non-sinus rhythm cardiac cycles overlaid on the physical map based on the received 3D positions and corresponding measured electrical potentials.

[0011] In some embodiments, the probe includes an intracardiac catheter having multiple electrodes that simultaneously generate respective sets of signals.

[0012] In additional embodiments, the non-sinus rhythm cardiac cycle includes a premature ventricular contraction.

[0013] In a further embodiment, generating the physical map includes generating the physical map based on 3D positions indicated by the set of signals received during the first cardiac cycle and the second cardiac cycle. In one embodiment, generating the physical map includes generating a first physical map based on 3D positions indicated by the set of signals received during the first cardiac cycle and a second physical map based on 3D positions indicated by the set of signals received during the second cardiac cycle, and selecting either the first physical map or the second physical map. In another embodiment, the second physical map follows the first physical map.

[0014] In a supplementary embodiment, rendering an electroanatomical map including regional activation arrival times of non-sinus rhythm cardiac cycles overlaid on the physical map includes overlaying the regional activation arrival times of non-sinus rhythm cardiac cycles indicated by each given signal at map locations corresponding to the 3D locations indicated by the given signals.

[0015] In some embodiments, comparing the received measurements of the electrical potential and their respective times with a given template comprises comparing a given signal indicative of the received measurements of the electrical potential and their respective times with the given template.

[0016] In additional embodiments, the method may include identifying a region of the map having an earliest local activation time and flagging the identified region for ablation on the display. In one embodiment, identifying a region of the map having an earliest local activation time includes partitioning the map into a plurality of regions based on the respective local activation times and identifying the region having the earliest local activation time.

[0017] Also in accordance with an embodiment of the present invention, an apparatus is provided having a display and a processor, the apparatus comprising: receiving a set of signals during a plurality of cardiac cycles, each set of signals indicating, for a medical probe inserted into a cardiac chamber, a three-dimensional (3D) position of a distal end of the probe, an electrical potential measured at the 3D position, and a respective time during a given cardiac cycle when the electrical potential was measured; and classifying the received electrical potential measurements and respective times relative to a first cardiac cycle in a sinus rhythm to identify a series of cardiac cycles including consecutive first, second, and third cardiac cycles. and a second template for non-sinus rhythm cardiac cycles, where the first and second cardiac cycles follow the first template and the third cardiac cycle follows the second template; generating a physical map of the ventricle based on the 3D positions; and rendering on a display an electroanatomical map including regional activation times for the non-sinus rhythm cardiac cycles overlaid on the physical map based on the received 3D positions and corresponding measured electrical potentials.

[0018] Further, in accordance with an embodiment of the present invention, there is provided a computer software product for operation with a medical probe for insertion into a body cavity, the computer software product including a non-transitory computer readable medium having stored thereon program instructions which, when read by a computer, cause the computer to: receive a set of signals during a plurality of cardiac cycles, each set of signals indicating, for a medical probe inserted into a cardiac chamber, a three-dimensional (3D) position of a distal end of the probe, an electrical potential measured at the 3D position, and a respective time during a given cardiac cycle when the electrical potential was measured; and generate a series of cardiac cycles including successive first, second, and third cardiac cycles. A computer software product is provided that causes the computer to: compare the received electrical potential measurements and their respective times to a first template for sinus rhythm cardiac cycles and a second template for non-sinus rhythm cardiac cycles to identify phases, where the first and second cardiac cycles follow the first template and the third cardiac cycle follows the second template; generate a physical map of the ventricle based on the 3D positions; and render on a display an electroanatomical map including regional activation arrival times for the non-sinus rhythm cardiac cycles overlaid on the physical map based on the received 3D positions and corresponding measured electrical potentials. [Brief description of the drawings]

[0019] The present disclosure is herein described, by way of example only, with reference to the accompanying drawings. [Figure 1A] 1 is a schematic, pictorial illustration of a medical system including a mapping catheter, in accordance with an embodiment of the present invention. [Figure 1B] 1 is a schematic, pictorial illustration of a medical system including a mapping catheter, in accordance with an embodiment of the present invention. [Diagram 2] 1 is a schematic, pictorial illustration of a distal end of a mapping catheter, in accordance with an embodiment of the present invention. [Diagram 3]1 is a flow chart that generally illustrates a method of using a mapping catheter in a mapping procedure to generate a map of the cardiac chambers based on signals collected during sinus rhythm and non-sinus rhythm cardiac cycles, in accordance with an embodiment of the present invention. [Figure 4] 1 is a schematic detailed view of a distal end of a mapping catheter in a cardiac chamber during a mapping procedure, according to an embodiment of the present invention. [Diagram 5] 1A-1C are schematic diagrams of electrocardiograms during sinus rhythm and non-sinus rhythm cardiac cycles, in accordance with an embodiment of the present invention. [Figure 6] FIG. 1 is a schematic diagram of an electroanatomical map including a first regional activation time for a sinus rhythm cardiac cycle and a second regional activation time for a non-sinus rhythm cardiac cycle overlaid on a physical map of the ventricles, in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Generating a local activation time (LAT) map of a heart with arrhythmia is typically a difficult and time-consuming process, as the LAT map is generated from information collected during sinus rhythm and non-sinus rhythm cardiac cycles, and selecting between different types of cardiac cycles (also known as beats) by a medical professional (e.g., a physician) can also be time-consuming.

[0021] Embodiments of the present invention provide a method and system for automatically generating an electroanatomical LAT hybrid map for mapping arrhythmic cardiac premature ventricular contractions (PVCs). As described below, an intracardiac probe is inserted into a cardiac ventricle and a set of signals is received during multiple cardiac cycles, each set of signals indicating the three-dimensional (3D) position of the distal tip of the probe, the electrical potentials measured at that 3D position, and the respective time during a given cardiac cycle at which the electrical potentials were measured.

[0022] The received measurements of electrical potentials and their respective times are compared to a first template for cardiac cycles in normal sinus rhythm (also referred to herein simply as sinus rhythm) and a second template for cardiac cycles in non-sinus rhythm to identify a series of cardiac cycles including consecutive first, second and third cardiac cycles, where the first and second cardiac cycles follow the first template and the third cardiac cycle follows the second template. A physical map of the ventricle is generated based on the received 3D arrangement and based on the received 3D arrangement and the corresponding measured electrical potentials, and an electroanatomical map including the regional activation arrival times of the non-sinus rhythm cardiac cycles overlaid on the physical map is provided for display. The resulting map then typically indicates the origin of the PVCs and can be used to select regions for ablation. Using templates to identify sinus rhythm and non-sinus rhythm cardiac cycles allows systems implementing embodiments of the present invention to rapidly generate electroanatomical LAT maps of an arrhythmic heart without requiring any user input to identify sinus rhythm and non-sinus rhythm cardiac cycles. In some embodiments, the physical map may be generated based solely on 3D coordinates received during the first and second cardiac cycles (i.e., sinus rhythm cardiac cycles). By using only 3D location coordinates collected from sinus rhythm cardiac cycles, embodiments of the present invention may create a more stable physical map with fewer errors due to the unstable or "jumpy" nature of adjacent non-sinus rhythm cardiac cycles such as PVCs.

[0023] System Description 1A and 1B are schematic illustrations of a medical system 20 including a medical probe 22 and a control console 24, and FIG. 2 is a schematic illustration of a distal end 26 of the medical probe 22, according to an embodiment of the present invention. The medical system 20 may be based on, for example, the CARTO® system manufactured by Biosense Webster Inc. (33 Technology Drive, Irvine, CA 92618 USA). In the embodiments described below, the medical probe 22 may be used for diagnostic or therapeutic procedures, such as for mapping electrical potentials of a heart 28 of a patient 30. In the embodiments described herein, the medical probe 22 may also be referred to as a mapping catheter. Alternatively, the medical probe 22 may be used for other therapeutic and / or diagnostic purposes in the heart or other body organs, mutatis mutandis.

[0024] During a medical procedure, the medical professional 34 inserts the medical probe 22 into a biocompatible sheath 80 (FIG. 2) that has been previously positioned in a body cavity (e.g., a ventricle of the heart 28) of the patient, such that the distal end 26 of the medical probe enters the body cavity. By way of example, as shown in FIG. 2, the distal end 26 of the probe 22 includes a flexible spline 82 formed on the end of a tubular shaft 86. During a medical procedure, the medical professional 34 can position the spline 82 by extending the tubular shaft from the sheath 80.

[0025] The control console 24 is connected by a cable 32 to the body surface electrodes, which typically include an adhesive skin patch 36 that is affixed to the patient 30. The control console 24 includes a processor 38 that, in conjunction with a current tracking module 40, determines position coordinates of the inner distal end 26 of the heart 28 based on impedance measured between the adhesive skin patch 36 and an electrode 84 affixed to a spline 82 shown in FIG. 2. In embodiments described herein, the electrode 84 may also be configured to apply a signal to tissue within the heart 28 and / or measure certain physiological properties (e.g., local surface potentials) at locations within the heart. The electrode 84 is connected to the control console 24 by wires (not shown) that run through the medical probe 22.

[0026] Although the embodiments herein show a probe 20 comprising a multi-spline intracardiac catheter such as a Pentaray® NAV catheter, the use of other multi-electrode intracardiac catheters such as the Navistar® Thermocool® catheter is also considered to be within the spirit and scope of the present invention. Both the Pentaray® NAV and Navistar® Thermocool® catheters are manufactured by Biosense Webster Inc.

[0027] The processor 38 may include a real-time noise reduction circuit 42, typically configured as a field programmable gate array (FPGA), followed by an analog-to-digital (A / D) ECG (electrocardiograph) signal conversion integrated circuit 44. The processor may communicate signals from the A / D ECG circuit 42 to another processor and / or may be programmable to execute one or more algorithms disclosed herein, each of which includes steps described below. The processor uses features of the circuitry 42 and circuitry 44, as well as modules described in more detail below, to execute the one or more algorithms.

[0028] 1A, 1B, and 2 use impedance-based sensing to measure the position of the distal end 26, although other position tracking techniques may be used (e.g., techniques using magnetic-based sensors). Impedance-based position tracking techniques are described, for example, in U.S. Pat. Nos. 5,983,126, 6,456,864, and 5,944,022, the disclosures of which are incorporated herein by reference. Magnetic position tracking techniques are described, for example, in U.S. Pat. Nos. 5,391,199, 5,443,489, 6,788,967, 6,690,963, 5,558,091, 6,172,499, and 6,177,792, the disclosures of which are incorporated herein by reference. The position sensing methods described herein above are implemented in the above-mentioned CARTO® system and are described in detail in the above-cited patents.

[0029] The control console 24 also includes an input / output (I / O) communication interface 46 that enables the control console to transfer signals from and / or to the electrodes 84 and adhesive skin patch 36. Based on the signals received from the electrodes 84 and / or adhesive skin patch 36, the processor 38 may generate an electroanatomical local activation arrival time (LAT) map 48 that provides a measure of cardiac conduction velocity, as described in the description below with reference to FIG.

[0030] During a procedure, the processor 38 may present the electroanatomical LAT map 48 to the medical professional 34 on a display 50 and may store data representing the electroanatomical LAT map in a memory 52. ​​The memory 52 may include any suitable volatile and / or non-volatile memory, such as RAM or a hard disk drive. In some embodiments, the medical professional 34 may manipulate the map 48 using one or more input devices 54. In an alternative embodiment, the display 50 may include a touch screen, which may be configured to receive input from the medical professional 34 in addition to presenting the map 48.

[0031] 1B, memory 52 stores signals 60 received by processor 38, with each given signal 60 including an ordered pair of sampling times 61 indicating when the given signal was received, and electrical potentials 62 measured by adhesive skin patch 36 or a given electrode 84, as described below. In FIG. 1B, signals 60 and their respective sampling times 61 and electrical potentials 62 are differentiated by appending a letter to an identification number such that signals include signals 60A-60C, sampling times include sampling times 61A-61C, and electrical potentials include electrical potentials 62A-62C. In the embodiment described herein, signal 60A includes a body surface ECG signal received from patch 36, signal 60B includes a position signal received from patch 36 and indicating the respective positions 63 of electrodes 84, and signal 60C includes an intracardiac ECG signal received from electrode 84.

[0032] 1B, the memory 52 also stores a set of electrode position records 64, a set of intracardiac ECG recordings 65, and a set of ECG templates 66. Each electrode position record 64 includes an electrode identifier (ID) 67 that indicates a given electrode 84, a set of position signals 60B received from the adhesive skin patch 36 for the given electrode, and a set of locations 63 having a one-to-one correspondence with the electrodes 84. Each given location 63 typically includes a set of 3D coordinates generated from the corresponding electrical potentials 62B.

[0033] In some embodiments, the electrode position records 64 have a one-to-one correspondence with the electrodes 84, and the processor 38 can initialize a set of electrode position records 64 by storing in each electrode ID 67 a unique numeric value or text string that indicates the corresponding electrode 84.

[0034] Each intracardiac ECG recording 65 includes an electrode ID 68 that indicates a given electrode 84 and a set of intracardiac ECG signals 60C received from the indicated electrode. In some embodiments, the intracardiac ECG recordings 65 have a one-to-one correspondence with the electrodes 84, and the processor 38 can initialize a set of intracardiac ECG recordings 65 by storing in each electrode ID 68 a unique numeric value or text string that indicates the corresponding electrode 84.

[0035] Each ECG template 66 includes a set of cardiac cycle types 69 and corresponding template ECG signals 70, each of which includes a time 71 and a potential 72. Examples of cardiac cycle types 69 include, but are not limited to, normal sinus rhythm and non-sinus rhythms such as premature ventricular contractions (PVCs).

[0036] During operation, the processor 38 may receive the signal 60 and store the received signal in the memory 52 using the following embodiments. The processor 38 receives the set of body surface ECG signals 60A from the adhesive skin patch 36 and stores the received set of body surface ECG signals in the memory 52. The processor 38 receives a corresponding set of position signals 60B for each electrode 84 from the adhesive skin patch 36. Upon receiving a given set of position signals 60B for a given electrode 84, the processor 38 may use the embodiments described above to calculate the locations 63 corresponding to the electrical potentials 62B in the given set of position signals 60B. The processor 38 may then identify a given electrode position record 64 whose electrode ID 67 indicates the given electrode, and store the given set of position signals 60B and its corresponding locations 63 in the identified electrode position record. Processor 38 receives each set of intracardiac ECG signals 60C from electrodes 84. Upon receiving each given set of intracardiac ECG signals 60C from a given electrode 84, processor 38 may identify a given intracardiac ECG recording 65 whose electrode ID 69 indicates that given electrode, and store the given set of intracardiac ECG signals 60C in that identified intracardiac ECG recording.

[0037] The control console 24 may also include an electrocardiogram (ECG) module 56 that may be configured to generate an ECG chart 58 from the body surface ECG signal 60A. In some embodiments, the processor 38 presents the ECG chart 58 (i.e., along with the LAT map 48) on the display 50. In addition to presenting the ECG chart 58 on the display 50, the processor 38 may store the ECG chart in the memory 52. ​​Further details of the ECG chart 58 are described in the referenced description of FIG. 5 below.

[0038] mapping Figure 3 is a flow chart that generally illustrates a method for mapping a ventricle of heart 28, and Figure 4 is a detailed schematic diagram of splines 82 engaging endocardial tissue 110 within a ventricle, in accordance with an embodiment of the present invention. At a loading step 90, processor 38 loads into memory 52 a plurality of templates 60, including at least one template 60 for a sinus rhythm cardiac cycle and at least one template 60 for a non-cardiac cardiac cycle.

[0039] At an inserting step 92, the medical professional 34 inserts the distal end 26 into the ventricle such that the splines 82 engage the endocardial tissue 110, and at an operating step 94, the medical professional 34 moves the splines of the distal end along the endocardial tissue 110 for multiple cardiac cycles. As the medical professional 34 moves the splines along the endocardial tissue for multiple cardiac cycles, the processor 38 receives, at a receiving step 96, the body surface ECG signal 60A, the position signal 60B, and the intracardiac ECG signal 60C.

[0040] In an identification step 98, the processor 38 identifies three consecutive cardiac cycles consisting of two sinus rhythm cardiac cycles followed by one non-sinus rhythm cardiac cycle by comparing the received body surface ECG signal 60A to an ECG template 66. In some embodiments, comparing the body surface ECG signal 60A to the template 66 includes comparing the sampling time 61A and potential 62A of the body surface ECG signal to the time 71 and potential 72 of the template.

[0041] As described above, a first given template 66 may be defined for cardiac cycles in sinus rhythm and a second given template 66 may be defined for cardiac cycles in non-sinus rhythm, such as premature ventricular contractions. In an embodiment of the present invention, the processor 38 may identify three cardiac cycles by comparing the body surface ECG signal 60A to the templates 66 and detecting that the body surface ECG signal during the first two cardiac cycles matches the first given template 66 for cardiac cycles in sinus rhythm and that the body surface ECG signal during the subsequent third cardiac cycle matches the second given template 66 for cardiac cycles in non-sinus rhythm. Thus, the processor 38 may identify a first set of sampling times 61 for the first two cardiac cycles and a second set of sampling times 61 for the third cardiac cycle.

[0042] To match the surface ECG signal 60A to the given template 66 during a given cardiac cycle, the processor 38 may perform a comparison between the surface ECG signal and the given template and may detect a match by comparing the comparison to a predefined threshold and determining that there is a high correlation (i.e., within a defined threshold) between the surface ECG signal and the given template. For example, the processor 38 may use a correlation threshold of 0.95 when comparing the surface ECG signal 60A to the given template 66 for non-sinus rhythm cardiac cycles and a correlation threshold of 0.9 when comparing the surface ECG signal to the given template 62 for sinus rhythm cardiac cycles.

[0043] Figure 5 is a schematic, pictorial illustration of an ECG chart 58, according to one embodiment of the present invention. The ECG chart 58 comprises a trace including lines 120 plotting along a vertical axis 122 the electrical potentials 61A of a given set of body surface ECG signals 60A against time along a horizontal axis 124, where the electrical potentials 61A are measured as voltages V and time is measured in units of seconds S. In the example shown in Figure 5, the lines 120 depict the electrical potentials 61A of a given set of body surface ECG signals 60A measured during a series of successive cardiac cycles 126, 128 and 130, where the cardiac cycles 126 and 128 are in sinus rhythm and the cardiac cycle 130 includes a premature ventricular contraction (i.e., an example of a non-sinus rhythm cardiac cycle).

[0044] Returning to the flowchart, in a first generating step 100, processor 38 generates a physical map of the ventricle based on the 3D coordinates indicated by positions 63, which are described below in the description with reference to FIG. 6. In some embodiments, as described above, processor 38 uses the 3D coordinates indicated by positions 63 obtained from position signals 60B whose respective sampling times 61B were between two sinus rhythm cardiac cycles (i.e., ignores the 3D coordinates indicated by positions 63 obtained from position signals 60B whose respective sampling times 61B were between non-sinus rhythm cardiac cycles) to create a more stable physical map.

[0045] Since the heart 28 is typically in sinus rhythm most of the time, using a physical map with 3D coordinates indicated by positions 63 obtained from position signals 60B whose respective sampling times 61B were during normal sinus rhythm cardiac cycles may help to create a more useful physical map. For example, during an ablation procedure using an ablation catheter (not shown), if a non-sinus rhythm cardiac cycle contains PVCs, the heart 28 will typically be in sinus rhythm with intermittent short PVC bursts. Thus, if the processor 38 were to create a physical map with 3D coordinates indicated by positions 63 obtained from position signals 60B whose respective sampling times 61B were during PVC cardiac cycles, there would likely be a mismatch between the positions of the map points (PVC geometry) and the position of the distal end 26, since the position of the ablation catheter would be displayed as sinus rhythm most of the time. As a result, any area that is ablated may not be optimal for correcting the patient's arrhythmia. It is believed that the geometry of the heart during sinus rhythm is different compared to the geometry during a non-sinus rhythm cardiac cycle, such as PVCs.

[0046] In a further embodiment, processor 38 may generate the physical maps by creating a first physical map for the 3D coordinates indicated by positions 63 obtained from position signals 60B whose respective sampling times 61B were during a first (i.e., sinus rhythm) cardiac cycle, creating a second physical map for the 3D coordinates indicated by positions 63 obtained from position signals 60B whose respective sampling times 61B were during a second (i.e., sinus rhythm) cardiac cycle, and selecting either the first physical map or the second physical map as the physical map. Physical maps are described below in the description with reference to FIG. 6.

[0047] In some embodiments, processor 38 may generate a physical map only if the body surface ECG signals 60A, whose respective sampling times 61B were during a first sinus rhythm cardiac cycle and a second sinus rhythm cardiac cycle, match (i.e., within a specified threshold) a given template 66 for sinus rhythm cardiac cycles. In other words, processor 38 may generate a physical map only if the first map and the second map are substantially the same (i.e., match each other).

[0048] In a second generating step 102, processor 38 generates map 48 including regional activation times for non-sinus rhythm cardiac cycles overlaid on the physical map based on locations 63 (i.e., as indicated by the location signal) and corresponding electrical potentials 62C (i.e., as indicated by the intracardiac ECG signal) measured by electrodes 84. (Overlaying PVC electrical data on a sinus rhythm physical map is described in U.S. Patent Application Publication No. 2015 / 0073246, the disclosure of which is incorporated herein by reference.) In other words, map 48 reflects the geometry of heart 28 during sinus rhythm, but with regional activation times of the heart while experiencing PVCs.

[0049] Finally, in a rendering step 104, the processor 38 renders the map 48 on the display 50, and the method ends. To render the map 48, the processor 38 may render a physical map 140 on the display 50 and overlay the regional activation arrival times of non-sinus rhythm cardiac cycles indicated by each given intracardiac ECG signal 60C on the rendered physical map at map locations corresponding to the locations indicated by the corresponding position signals (i.e., where sampling times 61B and 61C match). An example of overlaying regional activation arrival times on a physical map is described below in the discussion with reference to FIG. 6.

[0050] Figure 6 is a schematic, pictorial diagram illustrating a portion of a LAT map 48 that includes a physical map 140 of the ventricles of heart 28, in accordance with an embodiment of the present invention. In Figure 6, local activation arrival time information of map 48 is incorporated into physical map 140 and encoded using patterns according to a key 142. These patterns mimic the false colors of an actual functional map. From left to right, the patterns in key 142 correspond to a range of early to late LAT times (i.e., relative to a reference time for a given cardiac cycle).

[0051] Thus, in map 48, a first region 144 has a relatively early LAT and is surrounded by region 146 having a relatively late local activation arrival time. In the embodiments described herein, regions 144 and 146 include map locations that correspond to 3D locations indicated by the received signals. In operation, processor 38 of region 144 can identify and flag region 144 (i.e., the region in map 48 having the earliest LAT) as a region for ablation. Alternatively, a medical professional can select and flag regions 144 and / or 146 using input device 54.

[0052] It will be understood that the above-described embodiments are given by way of example, and that the present invention is not limited to what has been particularly shown and described above, but rather, the scope of the present invention includes both combinations and subcombinations of the various features as hereinabove described, as well as variations and modifications thereof not disclosed in the prior art that would occur to one skilled in the art upon reading the foregoing description.

[0053] [Embodiment] (1) A method for mapping regional activation times during sinus and non-sinus cardiac cycles, comprising: receiving, by a processor, sets of signals during a plurality of cardiac cycles, each set of signals indicating, for a medical probe inserted into a cardiac chamber, a three-dimensional (3D) position of a distal end of the probe, electrical potentials measured at the 3D positions, and a respective time during a given cardiac cycle when the electrical potentials were measured; comparing the received electrical potential measurements and the respective times to a first template for sinus rhythm cardiac cycles and a second template for non-sinus rhythm cardiac cycles to identify a series of cardiac cycles including consecutive first, second, and third cardiac cycles, wherein the first and second cardiac cycles conform to the first template and the third cardiac cycle conforms to the second template; generating a physical map of the ventricle based on the 3D positions; and and rendering on a display an electroanatomical map including the regional activation times of the non-sinus rhythm cardiac cycle overlaid on the physical map based on the received 3D positions and the corresponding measured electrical potentials. (2) The method of embodiment 1, wherein the probe comprises an intracardiac catheter having multiple electrodes that simultaneously generate respective sets of the signals. (3) The method of embodiment 1, wherein the non-sinus rhythm cardiac cycle includes a premature ventricular contraction. (4) The method of embodiment 1, wherein generating the physical map includes generating the physical map based on the 3D positions indicated by the set of signals received during the first cardiac cycle and the second cardiac cycle. (5) The method of embodiment 4, wherein generating the physical map includes generating a first physical map based on the 3D positions indicated by the set of signals received during the first cardiac cycle and a second physical map based on the 3D positions indicated by the set of signals received during the second cardiac cycle, and selecting either the first physical map or the second physical map.

[0054] (6) The method of embodiment 5, wherein the second physical map follows the first physical map. (7) The method of embodiment 1, wherein rendering the electroanatomical map including the regional activation arrival times of the non-sinus rhythm cardiac cycles overlaid on the physical map includes overlaying the regional activation arrival times of the non-sinus rhythm cardiac cycles indicated by each given signal at map locations corresponding to the 3D locations indicated by the given signals. (8) The method of embodiment 1, wherein comparing the received measurements of the electrical potential and the respective times with a given template includes comparing a given signal indicative of the received measurements of the electrical potential and the respective times with the given template. (9) The method of embodiment 1, comprising identifying a region of the map having the earliest local activation time; and flagging the identified region for ablation on the display. (10) The method of embodiment 9, wherein identifying the region of the map having the earliest local activation time includes dividing the map into a plurality of regions based on their respective local activation times and identifying the region having the earliest local activation time.

[0055] (11) An apparatus for mapping regional activation times during sinus rhythm and non-sinus rhythm cardiac cycles, comprising: A display and 1. A processor comprising: receiving a set of signals during a plurality of cardiac cycles, each set of signals indicating, for a medical probe inserted into a cardiac chamber, a three-dimensional (3D) position of a distal end of the probe, electrical potentials measured at the 3D positions, and a respective time during a given cardiac cycle when the electrical potentials were measured; comparing the received electrical potential measurements and the respective times to a first template for sinus rhythm cardiac cycles and a second template for non-sinus rhythm cardiac cycles to identify a series of cardiac cycles including consecutive first, second, and third cardiac cycles, wherein the first and second cardiac cycles conform to the first template and the third cardiac cycle conforms to the second template; generating a physical map of the ventricle based on the 3D positions; and and rendering on the display an electroanatomical map including the regional activation times of the non-sinus rhythm cardiac cycle overlaid on the physical map based on the received 3D positions and corresponding measured electrical potentials. (12) The apparatus of embodiment 11, wherein the probe comprises an intracardiac catheter having multiple electrodes that simultaneously generate respective sets of the signals. (13) The device of embodiment 11, wherein the non-sinus rhythm cardiac cycle includes a premature ventricular contraction. (14) The apparatus of claim 11, wherein the processor is configured to generate the physical map by generating the physical map based on the 3D positions indicated by the set of signals received during the first cardiac cycle and the second cardiac cycle. (15) The apparatus of embodiment 14, wherein the processor is configured to generate a first physical map based on the 3D positions indicated by the set of signals received during the first cardiac cycle and a second physical map based on the 3D positions indicated by the set of signals received during the second cardiac cycle, and to generate the physical maps by selecting either the first physical map or the second physical map.

[0056] (16) The apparatus of embodiment 15, wherein the second physical map follows the first physical map. (17) The apparatus of claim 11, wherein the processor is configured to render the electroanatomical map including the regional activation arrival times of the non-sinus rhythm cardiac cycles overlaid on the physical map by overlaying the regional activation arrival times of the non-sinus rhythm cardiac cycles indicated by each given signal at a map location corresponding to the 3D location indicated by the given signal. (18) The apparatus of claim 11, wherein the processor is configured to: compare the received measurements of the electrical potential and the respective times with a given template, including comparing a given signal indicative of the received measurements of the electrical potential and the respective times with the given template. (19) The apparatus of claim 11, wherein the processor is further configured to identify a region of the map having an earliest local activation time and flag the identified region for ablation on the display. (20) The apparatus of claim 19, wherein the processor is configured to identify the region of the map having the earliest local activation time by partitioning the map into a plurality of regions based on their respective local activation times and identifying the region having the earliest local activation time.

[0057] (21) A computer software product for operation in conjunction with a medical probe for insertion into a body cavity, comprising a non-transitory computer-readable medium having stored thereon program instructions which, when read by a computer, cause the computer to: receiving a set of signals during a plurality of cardiac cycles, each set of signals indicating, for a medical probe inserted into a cardiac chamber, a three-dimensional (3D) position of a distal end of the probe, electrical potentials measured at the 3D positions, and a respective time during a given cardiac cycle when the electrical potentials were measured; comparing the received electrical potential measurements and the respective times to a first template for sinus rhythm cardiac cycles and a second template for non-sinus rhythm cardiac cycles to identify a series of cardiac cycles including consecutive first, second, and third cardiac cycles, wherein the first and second cardiac cycles conform to the first template and the third cardiac cycle conforms to the second template; generating a physical map of the ventricle based on the 3D positions; and and rendering on a display an electroanatomical map including the activation times of the non-sinus rhythm cardiac cycles overlaid on the physical map based on the received 3D positions and the corresponding measured electrical potentials.

Claims

1. 1. A method of operation of an apparatus for mapping regional activation times of sinus rhythm and non-sinus rhythm cardiac cycles, the apparatus comprising a processor, a medical probe, and a display, the method comprising: receiving a set of signals during a plurality of cardiac cycles from the medical probe inserted into a cardiac chamber, each set of signals indicating a three-dimensional (3D) position of a distal tip of the medical probe, electrical potentials measured at the 3D positions, and a respective time during a given cardiac cycle when the electrical potentials were measured; the processor comparing the received electrical potential measurements and the respective times to a first template for sinus rhythm cardiac cycles and a second template for non-sinus rhythm cardiac cycles to identify a series of cardiac cycles including consecutive first, second, and third cardiac cycles, the first and second cardiac cycles conforming to the first template and the third cardiac cycle conforming to the second template; generating a physical map of the ventricle based on the 3D positions; and the processor rendering on the display an electroanatomical map including the regional activation times of the non-sinus rhythm cardiac cycles overlaid on the physical map based on the received 3D locations and the corresponding measured electrical potentials; generating the physical map includes generating the physical map based on the 3D positions indicated by the set of signals received during the first cardiac cycle and the second cardiac cycle. method.

2. The method of claim 1 , wherein the medical probe comprises an intracardiac catheter having multiple electrodes that simultaneously generate respective sets of the signals.

3. The method of claim 1 , wherein the non-sinus rhythm cardiac cycle comprises a premature ventricular contraction.

4. 2. The method of claim 1, wherein generating the physical map includes generating a first physical map based on the 3D positions indicated by the set of signals received during the first cardiac cycle and a second physical map based on the 3D positions indicated by the set of signals received during the second cardiac cycle, and selecting either the first physical map or the second physical map.

5. The method of claim 4 , wherein the second physical map is identical to the first physical map.

6. 2. The method of claim 1, wherein rendering the electroanatomical map including the regional activation arrival times of the non-sinus rhythm cardiac cycles overlaid on the physical map comprises overlaying the regional activation arrival times of the non-sinus rhythm cardiac cycles indicated by each given signal at map locations corresponding to the 3D locations indicated by the given signals.

7. 2. The method of claim 1, wherein comparing the received measurements of electrical potential and the respective times with a given template comprises comparing a given signal indicative of the received measurements of electrical potential and the respective times with the given template.

8. the processor identifying a region of the map having an earliest local activation time; The method of claim 1 , further comprising the processor flagging the identified region for ablation on the display.

9. 9. The method of claim 8, wherein identifying the region of the map having an earliest local activation time comprises partitioning the map into a plurality of regions based on respective local activation times and identifying the region having the earliest local activation time.

10. 1. An apparatus for mapping regional activation times of sinus rhythm and non-sinus rhythm cardiac cycles, comprising: A display and 1. A processor comprising: receiving a set of signals during a plurality of cardiac cycles, each set of signals indicating, for a medical probe inserted into a cardiac chamber, a three-dimensional (3D) position of a distal tip of the medical probe, electrical potentials measured at the 3D positions, and a respective time during a given cardiac cycle when the electrical potentials were measured; comparing the received electrical potential measurements and the respective times to a first template for sinus rhythm cardiac cycles and a second template for non-sinus rhythm cardiac cycles to identify a series of cardiac cycles including consecutive first, second, and third cardiac cycles, the first and second cardiac cycles conforming to the first template and the third cardiac cycle conforming to the second template; generating a physical map of the ventricle based on the 3D positions; and and rendering on the display an electroanatomical map including the regional activation times of the non-sinus rhythm cardiac cycles overlaid on the physical map based on the received 3D positions and the corresponding measured electrical potentials; the processor is configured to generate the physical map by generating the physical map based on the 3D positions indicated by the set of signals received during the first cardiac cycle and the second cardiac cycle. Device.

11. The apparatus of claim 10 , wherein the medical probe comprises an intracardiac catheter having multiple electrodes that simultaneously generate respective sets of the signals.

12. The apparatus of claim 10 , wherein the non-sinus rhythm cardiac cycle comprises a premature ventricular contraction.

13. 11. The apparatus of claim 10, wherein the processor is configured to generate a first physical map based on the 3D positions indicated by the set of signals received during the first cardiac cycle and a second physical map based on the 3D positions indicated by the set of signals received during the second cardiac cycle, and to generate the physical maps by selecting either the first physical map or the second physical map.

14. The apparatus of claim 13 , wherein the second physical map is identical to the first physical map.

15. 11. The apparatus of claim 10, wherein the processor is configured to render the electroanatomical map including the regional activation arrival times of the non-sinus rhythm cardiac cycles overlaid on the physical map by overlaying the regional activation arrival times of the non-sinus rhythm cardiac cycles indicated by each given signal at a map location corresponding to the 3D location indicated by the given signal.

16. 11. The apparatus of claim 10, wherein the processor is configured to: compare the received measurements of electrical potential and the respective times with a given template, comprising comparing a given signal indicative of the received measurements of electrical potential and the respective times with the given template.

17. 11. The apparatus of claim 10, wherein the processor is further configured to identify a region of the map having an earliest local activation time and flag the identified region for ablation on the display.

18. 18. The apparatus of claim 17, wherein the processor is configured to identify the region of the map having the earliest local activation time by partitioning the map into a plurality of regions based on respective local activation times and identifying the region having the earliest local activation time.

19. 1. A computer software product for operation with a medical probe for insertion into a body cavity, the product comprising a non-transitory computer readable medium having stored thereon program instructions that, when read by a computer, cause the computer to: receiving a set of signals during a plurality of cardiac cycles, each set of signals indicating, for a medical probe inserted into a cardiac chamber, a three-dimensional (3D) position of a distal tip of the medical probe, electrical potentials measured at the 3D positions, and a respective time during a given cardiac cycle when the electrical potentials were measured; comparing the received electrical potential measurements and the respective times to a first template for sinus rhythm cardiac cycles and a second template for non-sinus rhythm cardiac cycles to identify a series of cardiac cycles including consecutive first, second, and third cardiac cycles, the first and second cardiac cycles conforming to the first template and the third cardiac cycle conforming to the second template; generating a physical map of the ventricle based on the 3D positions; and rendering on a display an electroanatomical map including regional activation times of the non-sinus rhythm cardiac cycles overlaid on the physical map based on the received 3D locations and the corresponding measured electrical potentials; generating the physical map includes generating the physical map based on the 3D positions indicated by the set of signals received during the first cardiac cycle and the second cardiac cycle.

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