US 7,024,243 B1 · System and methods for preventing, detecting, and terminating pacemaker mediated tachycardia in biventricular implantable cardiac stimulation device

Abstract

Various techniques are described for preventing pacemaker mediated tachycardia (PMT) within biventricular pacing systems and for detecting and terminating PMT should it nevertheless arise. In a first prevention technique, refractory periods applied to the atrial channel are synchronized to begin with a second of a pair of ventricular pacing pulses to more effectively prevent T-wave oversensing on the atrial channel. In a second prevention technique, the sensitivity of the atrial channel is reduced during T-waves also to prevent T-wave oversensing. In a third prevention technique, template matching is performed on the ventricular channels to prevent T-wave oversensing. In a fourth prevention technique, T-wave detection windows are applied to both the ventricular and atrial channels subsequent to any paced or sensed events. In a first detection technique, PMT is detected based upon a degree of variation within V-pulse to P-wave pacing intervals. In a second detection technique, PMT is detected based upon a degree variation within ventricular pacing intervals. In either case, if the degree of variation is too low, indicative of PMT, ventricular refractory periods are expanded to terminate the PMT.

Claims7

Dependent claims

In an implantable cardiac stimulation device having a biventricular pacing system and a PMT detection and termination system for implant within a patient, a method comprising:

delivering a pair of biventricular pacing pulses to the left and right ventricles of the heart of the patient using the biventricular pacing system;
detecting PMT using the PMT detection and termination system;
and
controlling the biventricular pacing system using the PMT detection and termination system to terminate the PMT;
wherein detecting PMT comprises:
detecting intervals between ventricular pulses (V-pulses) and subsequent atrial depolarization signals within the atrial and ventricular channel signals;
determining a degree of variation within the intervals;
and
identifying PMT based on the degree of variation in the intervals;
and
wherein identifying PMT based on the degree of variation in the biventricular pacing intervals further comprises:
determining, based on the V-pulse to atrial depolarization signal intervals, when a next expected atrial depolarization signal should occur;
delivering a pacing pulse to the atria prior to the next expected atrial depolarization signal timed to render the atria refractory during the next expected atrial depolarization signal;
and
if an atrial depolarization signal nevertheless occurs at the expected time, verifying that PMT is occurring;
otherwise concluding that PMT has not occurred.

13 more elements

Dependencies are inferred from the claim text.

System and methods for preventing, detecting, and terminating pacemaker mediated tachycardia in biventricular implantable cardiac stimulation device

Life of this patent

System and methods for preventing, detecting, and terminating pacemaker mediated tachycardia in biventricular implantable cardiac stimulation device

Life of this patent

Abstract

Claims7