His-purkinje system capture detection

Patent metadata

Field	Value
Publication number	US-2020406041-A1
Application number	US-202016901110-A
Country	US
Kind code	A1
Filing date	Jun 15, 2020
Priority date	Jun 25, 2019
Publication date	Dec 31, 2020
Grant date	—

Abstract

A medical device is configured to sense a cardiac electrical signal and determine from the cardiac electrical signal at least one of a maximum peak amplitude of a positive slope of the cardiac electrical signal and a maximum peak time interval from a pacing pulse to the maximum peak amplitude. The device is configured to determine a capture type of the pacing pulse based on at least one or both of the maximum peak amplitude and the maximum peak time interval.

First claim

What is claimed is:

1 . A medical device, comprising:
a sensing circuit configured to sense a first cardiac electrical signal; a control circuit configured to:
determine, from the first cardiac electrical signal, at least one of a maximum peak amplitude of a positive slope of the first cardiac electrical signal and a maximum peak time interval from a pacing pulse to the maximum peak amplitude of the positive slope; and
determine a capture type of the pacing pulse as being one of non-selective His-Purkinje system capture or ventricular myocardial capture based on at least one of the maximum peak amplitude and the maximum peak time interval.

2 . The device of claim 1 , wherein the control circuit is further configured to:
determine a ratio of the maximum peak time interval to the maximum peak amplitude; compare the ratio to a threshold ratio; determine the capture type as non-selective His-Purkinje system capture in response to the ratio being less than or equal to the threshold ratio; and determine the capture type as only ventricular myocardial capture in response to the ratio being greater than the threshold ratio.

3 . The device of claim 2 , further comprising:
a therapy delivery circuit configured to deliver a test pacing pulse at a test pulse energy; wherein the control circuit is configured to establish the threshold ratio by:
determining a reference maximum peak amplitude of a positive slope of the first cardiac electrical signal and a reference maximum peak time interval from the test pacing pulse to the reference maximum peak amplitude;
determine a reference ratio of the reference maximum peak time interval to the reference maximum peak amplitude; and
establish the threshold based on the reference ratio.

4 . The device of claim 1 , wherein the control circuit is configured to determine the maximum peak amplitude by determining a maximum positive peak amplitude that corresponds to a maximum positive slope of a negative portion the first cardiac electrical signal.

5 . The device of claim 1 , wherein the control circuit is configured to:
determine at least one evoked response signal feature from the first cardiac electrical signal; compare the at least one evoked response signal feature to a selective His-Purkinje system capture threshold requirement; responsive to the at least one evoked response signal feature meeting the selective His-Purkinje system capture threshold requirement, detect selective His-Purkinje system capture by a pacing pulse; and responsive to the at least one evoked response signal feature not meeting the selective His-Purkinje system capture threshold requirement, analyze the first cardiac electrical signal for determining a capture type of a pacing pulse as being one of non-selective His-Purkinje system capture or ventricular myocardial capture.

6 . The device of claim 5 , wherein the control circuit is configured to determine the at least one evoked response signal feature by determining a feature of a negative portion of the evoked response signal in the first cardiac electrical signal.

7 . The device of claim 5 , wherein the control circuit is configured to determine the at least one evoked response signal feature from the first cardiac electrical signal by:
detecting a maximum positive peak of the first cardiac electrical signal; determining a post-peak slope of the first cardiac electrical signal following the maximum positive peak; comparing the post-peak slope to a slope threshold; and determining the capture type of a pacing pulse as selective His-Purkinje system capture in response to the post-peak slope being greater than the slope threshold.

8 . The device of claim 1 , further comprising a therapy delivery circuit configured to generate pacing pulses;
wherein the control circuit is configured to adjust a pacing pulse output setting of the therapy delivery circuit based on the determined capture type.

9 . The device of claim 1 , further comprising a therapy delivery circuit configured to generate pacing pulses;
wherein the control circuit is configured to control the therapy delivery circuit to generate pacing pulses according to a capture threshold test in response to determining the capture type as being ventricular myocardial capture.

10 . The device of claim 1 , wherein:
the sensing circuit is configured to sense a second cardiac electrical signal different than the first cardiac electrical signal; and the control circuit is configured to:
generate a differential signal from the first cardiac electrical signal;
determine a plurality of evoked response signal features from at least two of the first cardiac electrical signal, the differential signal, and the second cardiac electrical signal;
compare a plurality of different combinations of the plurality of evoked response signal features to respective threshold requirements, wherein comparing each one of the plurality of different combinations to the respective threshold requirements comprises comparing at least two of the plurality of evoked response signal features to respective threshold requirements; and
detect selective His-Purkinje system capture by a pacing pulse in response to at least one of the plurality of combinations of at least two of the plurality of evoked response signal features meeting the respective threshold requirements.

11 . A method, comprising:
sensing a first cardiac electrical signal; determining at least one of a maximum peak amplitude of a positive slope of the first cardiac electrical signal and a maximum peak time interval from a pacing pulse to the maximum peak amplitude; and determining a capture type of the pacing pulse as being one of non-selective His-Purkinje system capture or ventricular myocardial capture based on at least one of the maximum peak amplitude and the maximum peak time interval.

12 . The method of claim 11 , further comprising:
determining a ratio of the maximum peak time interval to the maximum peak amplitude; comparing the ratio to a threshold ratio; determining the capture type as non-selective His-Purkinje system capture in response to the ratio being less than or equal to the threshold ratio; and determining the capture type as only ventricular myocardial capture in response to the ratio being greater than the threshold ratio.

13 . The method of claim 12 , further comprising:
generating a test pacing pulse at a test pulse energy; establishing the threshold by:
determining a reference maximum peak amplitude of a positive slope of the first cardiac electrical signal and a reference maximum peak time interval from the test pacing pulse to the reference maximum peak amplitude;
determining a reference ratio of the reference maximum peak time interval to the reference maximum peak amplitude; and
establishing the threshold ratio based on the reference ratio.

14 . The method of claim 11 , wherein determining the maximum peak amplitude comprises determining a maximum peak amplitude that corresponds to a maximum positive slope of a negative portion the first cardiac electrical signal.

15 . The method of claim 11 , further comprising:
determining at least one evoked response signal feature from the first cardiac electrical signal; comparing the at least one evoked response signal feature to a selective His-Purkinje system capture threshold requirement; responsive to the at least one evoked response signal feature meeting the selective His-Purkinje system capture threshold requirement, detecting selective His-Purkinje system capture by a pacing pulse; and responsive to the at least

Assignees

• Medtronic Inc

Inventors

• Cao Jian
• Demmer Wade M
• Lybarger Maureen E
• Mattson Elizabeth A
• Sheldon Todd J
• Yang Zhongping
• Zhou Xiaohong

Classifications

• G06F2218/00

  Aspects of pattern recognition specially adapted for signal processing · CPC title

• G16H50/20

  for computer-aided diagnosis, e.g. based on medical expert systems · CPC title

• A61N1/3756

  Casings with electrodes thereon, e.g. leadless stimulators · CPC title

• A61N1/3714

  Atrial capture · CPC title

• A61N1/3706

  Pacemaker parameters (stimulation threshold A61N1/371) · CPC title