Abstract
A 60-year-old man with arrhythmogenic right ventricular cardiomyopathy was readmitted to exchange the battery of his implantable cardioverter-defibrillator (ICD). When a dual-chamber ICD was implanted 6 years ago, induced ventricular fibrillation (VF) was terminated successfully by a 20-joule shock. Since (1) he had been treated with a dual-coil shock lead (Sprint Fidelis) and (2) preoperative venography showed mild collateral flow to the left subclavian vein, a single-coil lead (Sprint Quattro) was also implanted. However, the single-coil defibrillation system was unable to terminate the induced VF with a 25-joule shock, and a maximum shock of 35 joules was required to resume sinus rhythm. Therefore, dual defibrillation shock pathways were created using the additional connection of the superior vena cava coil of the Fidelis lead to the ICD. As a result, induced VF was terminated successfully by 15∼25 joules, and the shock impedance was decreased from 63 to 39 ohms. Using a combined connection between two implanted leads and an ICD generator is uncommon, but it can help some patients, as in our case.