LEFT VENTRICULAR PACING PROTECTION IN THE CONTEXT OF MULTI-SITE LEFT VENTRICULAR PACING

• US 20140100625A1
• Filed: 12/11/2013
• Published: 04/10/2014
• Est. Priority Date: 12/20/2010
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Stahmann, Jeffrey E., Gilkerson, James O., Siejko, Krzysztof Z., Yu, Yinghong
• Granted Patent: US 9,149,641 B2
• Time in Patent Office: Days
• US Class Current: 607/18
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/36842 Multi-site stimulation in the same chamber
• CPC Class Codes: A61N 1/36843 Bi-ventricular stimulation

Abstract

In a pacing mode where the left ventricle is paced upon expiration of an escape interval that is reset by a right ventricular sense, there is the risk that the left ventricular pace may be delivered in the so-called vulnerable period that occurs after a depolarization and trigger an arrhythmia. To reduce this risk, a left ventricular protective period (LVPP) may be provided. Methods and devices for implementing an LVPP in the context of multi-site left ventricular pacing are described.

Claims

1. A cardiac pacing device, comprising:

pulse generation circuitry for generating pacing pulses;

sensing circuitry for sensing cardiac electrical activity;

a controller for detecting cardiac events that define pacing timing intervals and for controlling the delivery of pacing pulses in accordance with a programmed mode;

a switch matrix operable by the controller for connecting the pulse generation circuitry and sensing circuitry to selected electrodes in order to form selected sensing and pacing channels;

wherein the controller is programmed to;

sense cardiac activity through right ventricular and left ventricular sensing channels;

schedule delivery of paces through left ventricular pacing channels to a plurality of left ventricular pacing sites during a cardiac cycle interval that is reset by a right ventricular sense;

initiate a pace-initiated left ventricular protective period after a left ventricular pace to any of the left ventricular pacing sites, wherein during the pace-initiated left ventricular protective period the first scheduled pace to each of the plurality of left ventricular pacing sites is delivered and subsequent left ventricular paces to the plurality of left ventricular pacing sites are inhibited.

2. The device of claim 1 wherein the controller is further programmed to:

sense cardiac activity through a left ventricular sensing channel;

initiate a sense-initiated left ventricular protective period after a left ventricular sense during which all paces to the left ventricle are inhibited.

3. The device of claim 1 wherein the controller is further programmed to:

define selected refractory periods for sensing channels such that when a sensing channel is refractory either the sensing channel is disabled or sensed activity is ignored for purposes of cardiac event detection;

initiate post-pace refractory periods for both the right and left ventricular sensing channels when the first ventricular pace is delivered during a cardiac cycle; and

,

initiate a sense-initiated left ventricular protective period after a left ventricular sense during which all paces to the left ventricle are inhibited.

4. The device of claim 3 wherein the controller is further programmed to:

if a non-refractory left ventricular sense occurs during a pace-initiated or sense-initiated left ventricular protective period, restart and extend the left ventricular protective period as a sense initiated left ventricular protective period.

5. The device of claim 3 wherein the sensing circuitry configurable into a plurality of left ventricular sensing channels and wherein the controller is further programmed to:

if a non-refractory left ventricular sense occurs during a pace-initiated or sense-initiated left ventricular protective period in a selected left ventricular sensing channel, restart and extend the left ventricular protective period as a sense-initiated left ventricular protective period.

6. The device of claim 5 wherein the controller is further programmed to

if a non-refractory left ventricular sense occurs during a pace-initiated or sense-initiated left ventricular protective period in a left ventricular sensing channel other than the selected one, not restart and extend the left ventricular protective period as a sense-initiated left ventricular protective period.

7. The device of claim 3 wherein the controller is further programmed to, after a left ventricular pace during a pace-initiated left ventricular protective period, restart and extend the pace-initiated left ventricular protective period.

8. The device of claim 3 wherein, after a left ventricular pace during a pace-initiated left ventricular protective period, the controller is further programmed to not restart the pace-initiated left ventricular protective period.

9. The device of claim 1 wherein the controller is programmed to shorten the pace-initiated left ventricular protective periods with increasing heart rate.

10. The device of claim 2 wherein the controller is programmed to shorten each of the pace-initiated and sense-initiated left ventricular protective periods with increasing heart rate.

11. A method for operating a cardiac pacing device, comprising:

sensing cardiac activity through right ventricular and left ventricular sensing channels,

scheduling delivery of paces through left ventricular pacing channels to at least two left ventricular sites designated LV1 and LV2 during a cardiac cycle interval that is reset by a right ventricular sense;

initiating a first left ventricular protective period for site LV1 after a left ventricular pace to site LV1 or after a left ventricular sense during which further paces to site LV1 are inhibited;

initiating a second left ventricular protective period for site LV2 after a left ventricular pace to site LV2 or after a left ventricular sense during which further paces to site LV2 are inhibited.

12. The method of claim 11 further comprising scheduling delivery of paces through left ventricular pacing channels to one or more additional left ventricular sites and initiating a separate left ventricular protective period for each additional site after a pace to that site or a left ventricular sense.

13. The method of claim. 11 further comprising:

sensing cardiac activity at sites LV1 and LV2 through separate sensing channels;

initiating the left ventricular protective period for site LV1 only after a left ventricular pace to site LV1 or after a left ventricular sense at site LV1;

initiating the left ventricular protective period for site LV2 only after a left ventricular pace to site LV2 or after a left ventricular sense at site LV2.

14. The method of claim 11 wherein further comprising scheduling delivery of paces through left ventricular pacing channels to one or more additional left ventricular sites and initiating a separate left ventricular protective period for each additional site only after a pace to that site or a left ventricular sense at that site.

15. The method of claim 11 further comprising shortening each of the left ventricular protective periods with increasing heart rate.

16. A method for operating a cardiac pacing device, comprising:

sensing cardiac activity through a right ventricular sensing channel;

scheduling delivery of paces through left ventricular pacing channels to a plurality of left ventricular pacing sites during a cardiac cycle interval that is reset by a right ventricular sense;

initiate a pace-initiated left ventricular protective period after a left ventricular pace to any of the left ventricular pacing sites, wherein during the pace-initiated left ventricular protective period the first scheduled pace to each of the plurality of left ventricular pacing sites is delivered and subsequent left ventricular paces to the plurality of left ventricular pacing sites are inhibited.

17. The method of claim 16 wherein further comprising:

sensing cardiac activity through a left ventricular sensing channel;

initiating a sense-initiated left ventricular protective period after a left ventricular sense during which all paces to the left ventricle are inhibited.

18. The method of claim 17 further comprising:

defining selected refractory periods for sensing channels such that when a sensing channel is refractory either the sensing channel is disabled or sensed activity is ignored for purposes of cardiac event detection;

initiating post-pace refractory periods for both the right and left ventricular sensing channels when the first ventricular pace is delivered during a cardiac cycle;

if a non-refractory left ventricular sense occurs during a pace-initiated or sense-initiated left ventricular protective period, restarting and extending the left ventricular protective period as a sense-initiated left ventricular protective period.

19. The method of claim 16 further comprising, after a left ventricular pace during a pace-initiated left ventricular protective period, restarting and extending the left ventricular protective period as a pace-initiated left ventricular protective period.

20. The method of claim 17 further comprising shortening each of the pace-initiated and sense-initiated left ventricular protective periods with increasing heart rate.