Antitachycardia Pacing Pulse from a Subcutaneous Defibrillator

• US 20120316613A1
• Filed: 06/07/2012
• Published: 12/13/2012
• Est. Priority Date: 06/09/2011
• Status: Active Grant

• Current Assignee: Cameron Health Inc (Boston Scientific Corporation)
• Original Assignee: Cameron Health Inc (Boston Scientific Corporation)
• Inventors: Keefe, James M., Sanghera, Rick
• Granted Patent: US 9,849,291 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• CPC Class Codes: A61N 1/0504 Subcutaneous electrodes
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/39622 Pacing therapy

Abstract

Devices and methods for single therapy pulse (STP) therapy for tachyarrythmia are disclosed. The STP therapy can be delivered from a far-field position to allow a “global” capture approach to pacing. Due to the global capture in STP, a series of pulses, which is indicative of conventional anti-tachycardia pacing (ATP) delivered by transvenous systems, becomes unnecessary. One to four pulses at most are needed for STP, and after delivery of the one to four pulses, therapy delivery can be interrupted to determine whether the previously delivered therapy has been successful.

Claims

1. A method of treating a patient in an implantable cardiac rhythm management device (CRMD) comprising a canister housing circuitry for performing data analysis and therapy delivery, coupled to a lead electrode having electrodes for body implantation suitable for sensing electrical signals, the method comprising:

receiving cardiac signals from the patient using one or more of the electrodes on the lead;

identifying that a tachycardia is occurring based on the received cardiac signals showing a cardiac rate in excess of a rate threshold;

determining that the tachycardia is not supraventricular in nature and declaring a treatable episode of tachycardia;

determining that the tachycardia is monomorphic;

delivering one to four synchronized pacing pulses to the patient using far-field electrodes;

calculating the cardiac rate of the patient following the delivery of the one to four synchronized pacing pulses;

determining that the cardiac rate dropped in response to the one to four synchronized pacing pulses; and

terminating the episode.

2. The method of claim 1 wherein the CRMD is a subcutaneous-only CRMD and the far-field electrodes used for therapy delivery are subcutaneously placed electrodes.

3. The method of claim 1 wherein the CRMD is a transvenous CRMD having at least one transvenous lead, and the far-field electrodes used for therapy delivery include a transvenous coil electrode and an electrode disposed on the canister.

4. The method of claim 1 wherein the rate threshold is in the range of 120-220 beats per minute.

5. An implantable cardiac rhythm management device (CRMD) comprising a canister housing operational circuitry for performing data analysis and therapy delivery, coupled to a lead electrode assembly having electrodes for body implantation suitable for sensing electrical signals, wherein the operational circuitry is configured to perform a method comprising:

the operational circuitry receiving cardiac signals from the patient using one or more of the electrodes on the lead;

the operational circuitry identifying that a tachycardia is occurring based on the received cardiac signals showing a cardiac rate in excess of a rate threshold;

the operational circuitry determining that the tachycardia is not supraventricular in nature and declaring a treatable episode of tachycardia;

the operational circuitry determining that the tachycardia is monomorphic;

the operational circuitry delivering one to four synchronized pacing pulses to the patient using far-field electrodes defined by the lead electrode assembly and/or canister;

the operational circuitry calculating the cardiac rate of the patient following the delivery of the one to four synchronized pacing pulses;

the operational circuitry determining that the cardiac rate dropped in response to the one to four synchronized pacing pulses; and

the operational circuitry terminating the episode and storing data related to the episode in memory.

6. The CRMD of claim 5 wherein the CRMD is a subcutaneous-only CRMD and the lead electrode assembly is designed for subcutaneous placement, such that the far-field electrodes are designed for subcutaneous placement.

7. The CRMD of claim 5 wherein the CRMD is a transvenous CRMD and the lead electrode assembly is configured for transvenous placement and includes a coil electrode such that far-field electrodes used for therapy delivery include the coil electrode and an electrode disposed on the canister.

8. The CRMD of claim 5 wherein the operational circuitry is configured such that the rate threshold is in the range of 120-220 beats per minute.

9. A method of treating a patient with an implantable cardiac stimulus device comprising:

identifying, by analysis of the patient'"'"'s cardiac signal, an elevated rate condition;

using only subcutaneously disposed electrodes, delivering a single termination pulse therapy to terminate the elevated rate condition if the elevated rate condition meets first predetermined conditions;

or

delivering a defibrillation therapy to terminate the elevated rate condition if the elevated rate condition meets second predetermined conditions;

wherein;

the single termination pulse therapy is delivered at a first energy level and the defibrillation therapy is delivered at a second energy level and the first energy level is less than the second energy level, and

the first predetermined conditions require monomorphic morphology of the cardiac signal, while the second predetermined conditions do not require monomorphic morphology of the cardiac signal.

10. The method of claim 9 wherein the first energy level is configured to capture the myocardium in a region of a reentrant circuit, and the second energy level is configured to depolarize a majority of the myocardium.

11. The method of claim 9 wherein the first energy level is less than 1% of the second energy level.

12. The method of claim 11 wherein the defibrillation therapy delivers energy is in the range of about 10-100 joules, and the single termination pulse therapy delivers energy in the range of about 10 to 1000 millijoules.