Analysis and detection for arrhythmia drivers

Patent metadata

Field	Value
Publication number	US-9427169-B2
Application number	US-201414273458-A
Country	US
Kind code	B2
Filing date	May 8, 2014
Priority date	May 8, 2013
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

Systems and methods are provided to detect and analyze arrhythmia drivers. In one example, a system can include a wave front analyzer programmed to compute wave front lines extending over a surface for each of the plurality of time samples based on phase information computed from electrical data at nodes distributed across the surface. A trajectory detector can be programmed to compute wave break points for each of the wave front lines and to determine a trajectory of at least one rotor core across the surface. A stability detector can be programmed to identify at least one stable rotor portion corresponding to subtrajectories of the determined trajectory.

First claim

What is claimed is:

1. A non-transitory computer-readable medium having instructions executable by a processor, the instructions programmed to perform a method comprising:
determining a pair of wave break points for each identified wave front line at a given time sample of a plurality of time samples;
for each other of the plurality of time samples:
evaluating a spatial distance for a given wave break point relative to each active trajectory in a previous time sample to identify a closest active trajectory, each respective trajectory in the previous time sample being an active trajectory if updated within a predetermined time period from a current time sample time, wherein evaluating comprises comparing the spatial distance relative to a predetermined threshold distance to identify the closest active trajectory;
appending the given wave break point to update the closest active trajectory if the spatial distance is less than the predetermined threshold distance; and
repeating the evaluating and the appending for each wave break point over the plurality of time samples to generate a set of at least one rotor trajectory.

2. The medium of claim 1 , wherein the method further comprises:
computing a duration for each rotor trajectory in the set of at least one rotor trajectory; and
removing a given rotor trajectory from the set of at least one trajectory if the computed duration for the given rotor trajectory does not have at least a predetermined duration to provide an adjusted set of at least one rotor trajectory.

3. The medium of claim 1 , further comprising beginning a new trajectory with the given wave break point if the evaluating indicates that the closest trajectory for a current time sample is greater than the predetermined threshold distance or if the closest active trajectory already has been updated for the current time sample.

4. The medium of claim 1 , further comprising determining whether each trajectory is active or inactive for a current time sample based on whether or not each respective trajectory was updated within a threshold number of one or more previous time samples relative to the current time sample.

5. The medium of claim 1 , wherein the wave front lines are generated by:
computing phase values for a plurality of nodes distributed across a geometric surface based on data representing the electrical activity for the plurality of nodes over time;
evaluating the computed phase values for each of the nodes at a given time to identify each pair of adjacent nodes having phase values that encompass a predetermined phase threshold; and
determining at least one location on the geometric surface, corresponding to a wave front at the given time, based on the evaluating; and
wherein determining the pair of wave break points for a current time sample is computed for each non-spatially looping wave front line generated for the current time sample.

6. The medium of claim 1 , wherein the method further comprises:
computing a stability value for each of the least one rotor trajectory based on at least one of a temporal, angular and spatial characteristic for each respective rotor trajectory; and
identifying at least one stable subtrajectory of each of the least one rotor core trajectory based on the stability value relative to a stability threshold value.

7. The medium of claim 6 , wherein for each rotor trajectory in the set of at least one rotor trajectory, the method further comprises executing at least two of:
computing a distance parameter representing a spatial distance traversed by each respective trajectory,
computing a duration parameter for each respective trajectory, and
computing at least one angular statistics parameter for a rotor corresponding to each respective trajectory;
wherein the at least one stable subtrajectory is determined based on filtering applied to the executed at least two computations.

8. The medium of claim 7 , wherein the at least one angular statistics parameter further comprises at least one of a rotation rate for the rotor, an angular acceleration for the rotor, a number of rotations for the rotor, a rotation cycle length for the rotor, and a direction of rotation for the rotor for a plurality of time samples.

9. The medium of claim 6 , further comprising generating a graphical map of the at least one stable subtrajectory on a graphical representation of the geometric surface.

10. The medium of claim 6 , wherein the at least one stable subtrajectory comprise at least two stable subtrajectories, the method further comprising computing an indication of connectivity between the at least two stable subtrajectories based on a number of at least one wave front line linking the at least two stable subtrajectories.

11. The medium of claim 10 , wherein the method further comprises determining that a pair of the stable subtrajectories are stably connected based on the indication of connectivity exceeding a time-based threshold.

12. The medium of claim 6 , further comprising calculating statistics data describing electrical activity for a set of selected neighboring nodes around the identified at least one stable subtrajectory.

13. The medium of claim 12 , wherein the method further comprises computing an index representing a sustainability of at least one arrhythmia driver residing within at least one spatial region on the geometric surface, wherein the index comprises an integer or fractional value to quantify the sustainability of the at least one arrhythmia driver.

14. The medium of claim 12 , wherein the index is computed based on an average number of rotations by one or more rotors residing within the spatial region on the geometric surface.

15. The medium of claim 1 , further comprising generating a graphical map comprising a graphical representation of the given trajectory on a graphical representation of the geometric surface.

16. The medium of claim 1 , wherein the method further comprises controlling at least one therapy delivery parameter based on stored arrhythmia driver data corresponding to the set of at least one rotor trajectory.

17. A system comprising: memory to store machine readable instructions and data, the data comprising store electrical data representing electrical activity for a plurality of nodes distributed across a geometric surface over a plurality of time samples; at least one processor to access the memory and execute the instructions, the instructions comprising: an arrhythmia driver analyzer comprising: a wave front analyzer programmed to compute wave front lines extending over a surface for each of the plurality of time samples based on phase information computed from electrical data at nodes distributed across the surface for each of the plurality of time samples; a trajectory detector programmed to compute wave break points for each of the wave front lines and to determined a trajectory of at least one rotor core across the surface based on applying temporal and spatial constraints to the wave break points through a sequence of the time samples, the determined trajectory being stored as arrhythmia driver data in the memory, wherein applying the spatial constraints to the wave break points comprises: comparing a spatial distance for a given wave break point relative to another wave break point through the sequence of the time samples relative to a predetermined threshold distance; and appending the other wave break point to the given wave break point through the sequence of time samples to define the trajectory of the at least one rotor core if the spatial distance is less than the predetermined thres

Assignees

• Cardioinsight Technologies Inc

Inventors

• Zeng Qingguo
• Jia Ping
• Bokan Ryan
• George Brian P
• Ramanathan Charulatha
• Vasudevan Venkatesh
• Strom Maria

Classifications

• A61N2007/0043

  intra-cavitary · CPC title

• A61N1/056

  Transvascular endocardial electrode systems · CPC title

• A61B2034/105

  Modelling of the patient, e.g. for ligaments or bones · CPC title

• G16H50/50

  for simulation or modelling of medical disorders · CPC title

• A61B2018/0212

  using an instrument inserted into a body lumen, e.g. catheter · CPC title