How many transvenous coils are optimal for defibrillators: One, two, or none?

Abstract

This year marks the 20th anniversary of the transvenous defibrillation lead. Until 1993, implantable cardioverter-defibrillator (ICD) implantation required thoracotomy for the placement of epicardial or extrapericardial patches, sometimes with transvenous pace/sense leads or shocking coils. The early transvenous defibrillation leads consisted of sensing electrodes and 2 coils tunneled to an abdominal pulse generator. Adequate defibrillation was often a challenge, but this problem was markedly reduced with 2 major technological advances: biphasic waveforms and downsizing of pulse generators to allow for pectoral implantation using the pulse generator as part of the shock pathway as an active “can.”