Patent ID: 8185198

Claim:
A method of identifying treatable cardiac conditions in an implantable cardiac stimulus device (ICSD), the ICSD comprising a plurality of electrodes for implantation in a patient and operational circuitry electrically coupled to the electrodes and configured to perform analysis of cardiac signals to identify malignant conditions, the method comprising: monitoring a signal captured between the electrodes; observing a plurality of events in the monitored signal; performing waveform appraisal on each observed event; certifying at least some of the observed events for use in event classification; marking at least one of the observed events as a suspect event, such that all events are either certified or marked as suspect; performing event classification using the certified observed events to determine whether the certified observed events suggest a need for cardiac electrical therapy to generate a number of classification outcomes; tracking classification outcomes using an X-out-of-Y counter; and determining whether the X-out-of-Y counter exceeds a threshold and, if so, declaring a malignant condition; wherein the X-out-of-Y counter uses only certified observed events, and any suspect events are excluded from the X-out-of-Y counter, such that the at least one observed event that is marked as a suspect event is not counted in either X or Y of the X-out-of-Y counter.