Cardiac Resynchronization by Restoration of Native Ventricular Activation

Abstract

A 56-year-old woman was transferred to our institution for evaluation of New York Heart Association class IV congestive heart failure that was refractory despite treatment with furosemide, carvedilol, digitalis, spironolactone, and valsartan. She was bedridden before her transfer and was referred for consideration of cardiac transplantation. Prior treatment at another institution included bypass of the left anterior descending coronary artery, a left internal mammary graft for unstable angina, and implantation of a dual-chamber cardioverter/defibrillator for ventricular tachycardia. The device was programmed for DDDR pacing, with rate limits of 80 to 130 bpm and an atrioventricular (AV) delay of 160 ms. In this setting, the patient had been paced in the right ventricle 100% of the time for 6 months before she presented at our institution. Deterioration of her condition began after cardioverter/defibrillator placement and persisted despite increasing pharmacotherapy. At the time of hospital admission, she was in florid congestive heart failure and had hypotension, elevated jugular venous pressure, bilateral lung crepitations, a murmur of mitral regurgitation, and pitting edema of the lower extremities. The initial ECG (at hospital admission) showed AV sequential pacing at 80 bpm …