Cardiac resynchronization therapy in patients with absent right but persistent left superior vena cava.

Abnormalities of the vena cava system are usually asymptomatic and are found incidentally during pacemaker implantation or catherization. We report a case of dilative cardiomyopathy requiring cardiac resynchronization defibrillator therapy (CRT-D). During the operation, a persistent left superior vena cava with an absent right vena cava was discovered. During open chest surgery, we implanted a CRT-D with epicardial patches and pacing leads, which is a simple technique for safe and reliable biventricular defibrillator therapy in these patients.