Patent ID: 7363080

Claim:
A system for providing bradycardia therapy in the presence of a system fault, comprising: a ventricular sensing circuit; a pacing pulse generator; a primary controller for controlling the operation of the pacing pulse generator in accordance with a programmed pacing mode; fault monitoring circuitry; a safety core pacemaker which is activated upon detection of a system fault which initiates a system reset and halts the primary controller; wherein the safety core pacemaker is a hardware-based logic circuit which comprises an escape interval timer which upon expiration causes the pacing pulse generator to deliver a ventricular pacing pulse and which is reset by a ventricular pace or sense; wherein the primary controller is configured to disable the safety core pacemaker when the primary controller successfully completes its reset sequence; and, wherein the safety core pacemaker is configured to operate in parallel to the primary controller using an escape interval set to the maximum pacing interval that is allowed for the system when the safety core pacemaker is disabled by the primary controller.