Patent ID: 7373200

Claim:
A system for providing tachyarrhythmia therapy in the presence of a system fault, comprising: a ventricular sensing circuit; a shock pulse generator; a primary controller for controlling the operation of the shock pulse generator; fault monitoring circuitry; a safety core defibrillator which is configured to be activated upon detection of a system fault which initiates a system reset and halts the primary controller; wherein the safety core defibrillator is a hardware-based logic circuit which measures the intervals between successive ventricular senses and causes the shock pulse generator to deliver a shock pulse if the ventricular rate is above a specified threshold; and, wherein the safety core defibrillator is configured to be automatically disabled in the event of charge faults during operation in order to prevent therapy retries when the shock pulse output circuits has been damaged or in the event that the battery capacity is insufficient to delivery therapy.