Dual chamber pacing system and method utilizing detection of ventricular fusion for adjustment of the atrial-ventricular delay as therapy for hypertrophic obstructive cardiomyopathy

摘要

A dual chamber pacemaker (6) for providing ventricular pace pulses synchronized with atrial senses or paces, and having specific control for optimizing the AV escape interval and resultant AV delay for purposes of therapy for a patient with hypertrophic obstructive cardiomyopathy (HOCM). The pacemaker has an algorithm (Fig. 4) for varying the AV escape interval (442, 443) and detecting when the AV delay is lengthened to the point of evoking a fusion beat (437, 438), thereby providing an accurate indication of a patient's underlying PR interval without significant loss of pacing capture. By monitoring T-wave detection (435) and drop in amplitude of the evoked T-wave (438), an algorithm is enabled for optimizing the pacemaker AV delay within a range of values just less than the longest value for obtaining pre-excitation by the delivered pace pulse.