Abstract
A left superior vena cava persistence was found in a 61 year-old patient affected by dilated and hypokinetic cardiopathy with severe dysfunction of the left ventricle (left ventricular ejection fraction of 32%) and valvular disease. After a negative coronary angiography, he was implanted with a cardiac resynchronization therapy with defibrillation function device (CRT-D). The present case describes the successful implantation of a biventricular defibrillator in this challenging congenital abnormality of cardiac venous system.