Patent ID: 7113824

Claim:
A method, comprising: sensing atrial events and ventricular events; determining ventricular interval rates from pairs of consecutively sensed ventricular events in a detection window, the detection window including a predetermined series of the most recent consecutive ventricular events; comparing each of the ventricular interval rates in the detection window to a lower rate threshold value for each of two or more rate zones; classifying a ventricular interval rate of the ventricular interval rates as a fast ventricular interval for a rate zone of the two or more rate zones when the ventricular interval rate is equal to or greater than the lower rate threshold value of the rate zone; declaring the detection window satisfied when a first predetermined percentage of the ventricular interval rates in the detection window are classified as fast ventricular intervals for the rate zone of the two or more rate zones; starting a first time interval once the detection window is declared satisfied, the first time interval having a duration allowing monitoring and analysis of cardiac rhythms for assessing an origin of the fast ventricular intervals; and determining whether to inhibit ventricular tachycardia therapy at the end of the first time interval based on the analysis of cardiac rhythms.