Patent ID: 8437842

Claim:
A method, comprising: obtaining a plurality of cardiac event intervals, at least a portion of the plurality of intervals corresponding to a tachycardia interval; sensing a first cardiac event having a morphology corresponding to a supraventricular beat; obtaining evidence of a rhythm breaking point preceding the first cardiac event; and detecting a non-treatable rhythm in response to the plurality of cardiac event intervals and the evidence of the rhythm breaking point, wherein obtaining evidence of a rhythm breaking point comprises: sensing a preceding cardiac event, the preceding cardiac event and the first cardiac event being consecutive cardiac events; measuring an interval between the first cardiac event and the preceding cardiac event; generating an event interval threshold; comparing the measured interval to the event interval threshold; and detecting a long pause in response to the interval being longer than the event interval threshold, the method further comprising: obtaining evidence of an undersensed cardiac event in response to detecting the long pause; and cancelling the long pause detection in response to obtaining the evidence of an undersensed cardiac event.