Patent ID: 6889077

Claim:
An implantable cardiac stimulation device that applies defibrillating electrical energy to at least one atrium of a heart at a time which avoids inducing ventricular fibrillation of the heart, the device comprising: an atrial fibrillation detector that detects atrial fibrillation of the heart; a pacing pulse generator that applies a pacing pulse to at least one of the ventricles responsive to the atrial fibrillation detector detecting atrial fibrillation of the heart; a timer that times a time period through an evoked response end a T-wave caused by the pacing pulse, the time period completing a predetermined time period after the T-wave ends; and a defibrillation pulse generator that applies the defibrillating eletrical energy to the at least one atrium of the heart responsive to the timer completing the timing of the time period.