Patent ID: 7477942
Filing Date: 2009-01-13
Classification: A61N

Abstract:
1. A method for delivering anti-tachyarrhythmia therapy, comprising: generating an electrogram signal representing electrical activity in a ventricle; detecting ventricular senses and measuring a time interval between ventricular senses (RR intervals) to determine a current ventricular rate; detecting a ventricular tachyarrhythmia when the ventricular rate exceeds a specified tachycardia detection rate (TDR); upon detection of a ventricular tachyarrhythmia, delivering anti-tachycardia pacing (ATP) therapy if the ventricular rate is below a fibrillation detection rate (FDR); wherein a specified rate stability criterion requires a predetermined degree of regularity in the intervals between successive ventricular beats; wherein a specified monomorphic morphology criterion requires a predetermined degree of similarity in the electrogram waveforms of successive ventricular beats; upon detection of a ventricular tachyarrhythmia and if the ventricular rate is above the FDR, determining if a specified number of beats during the tachyarrhythmia meet the specified rate stability criterion and the specified monomorphic morphology criterion; if the specified rate stability and monomorphic morphology criteria are met, delivering anti-tachycardia pacing (ATP) therapy; and, if the specified rate stability and monomorphic morphology criteria are not met, delivering shock therapy.