Patent ID: 8437849

Claim:
An implantable cardioverter/defibrillator (ICD), comprising: a pacing circuit configured to deliver atrial and ventricular pacing pulses; a defibrillation circuit configured to deliver ventricular defibrillation pulses; a cardiac sensing circuit configured to sense cardiac signals; a rate detector configured to detect an atrial rate and a ventricular rate using the cardiac signals; a tachyarrhythmia detection and classification circuit coupled to the rate detector, the tachyarrhythmia detection and classification circuit including: a tachyarrhythmia detector configured to detect tachyarrhythmia using the ventricular rate and one or more tachyarrhythmia threshold rates; and a tachyarrhythmia classifier configured to classify the detected tachyarrhythmia as a ventricular tachyarrhythmia using one or more criteria including the ventricular rate being greater than the atrial rate and detect one or more indications for an atrial tachyarrhythmia; and a controller, coupled to the pacing circuit, the defibrillation circuit, and the tachyarrhythmia detection and classification circuit, the controller configured to control the delivery of the atrial and ventricular pacing pulses and the ventricular defibrillation pulses, the controller including: an atrial pacing initiator configured to initiate the delivery of the atrial pacing pulses in a selected atrial pacing mode during the detected tachyarrhythmia and prior to a scheduled delivery of the ventricular pacing pulses or the ventricular defibrillation pulses in response to the detected tachyarrhythmia being classified as the ventricular tachyarrhythmia and one or more indications for the atrial tachyarrhythmia being detected; and a ventricular pacing and defibrillation confirmation circuit configured to determine whether the scheduled delivery of the ventricular pacing pulses or the ventricular defibrillation pulses is to be initiated after the delivery of the atrial pacing pulses.