Responding a partial lead failure in an implantable cardioverter defibrillator

摘要

An implanted cardioverter defibrillator (ICD) delivers an electrical therapy signal to the heart of a patient. When ventricular fibrillation or another condition of the heart requiring high voltage therapy is sensed, the therapy signal is delivered to the heart. When a partial short-circuit or other low impedance condition occurs, an over-current protection circuit will stop delivery of a shocking pulse. The ICD will then reduce the voltage of the shocking pulse and try again to deliver electrical therapy. This process is repeated until a voltage level is found that is able to deliver the electrical therapy without causing an over-voltage condition. Alternate lead configurations may also be tried in an attempt to find a signal path that is not affected by the low impedance or short-circuit condition.