Use of the Abiomed BVS System 5000 as a bridge to cardiac transplantation

Abstract

The Abiomed BVS System 5000 (Abiomed Cardiovascular, Inc., Danvers, Mass.) is a gravity-filled, pneumatically driven external prosthetic ventricle that has been implanted as a circulatory support device in six patients 9 to 58 years of age, presenting with a refractory heart failure nonamenable to any type of corrective operation. Three (including a 9-year-old girl) had an end-stage nonobstructive myocardiopathy, and two (including one patient who had had a massive recent myocardial infarction) had an ischemic heart disease. When first seen, the 58-year-old patient had an acute rejection and graft failure occurring 2 months after a first transplantation. All patients showed evidence of a low-output state (cardiac index less than 1.5 L/min/m2), with renal failure (mean urinary output, less than 27 ml/min) and hypoxia (mean arterial oxygen pressure = 56 torr under 80% forced inspiratory oxygen), despite maximum pharmacologic support (dobutamine, 16 to 18 gamma/kg/min; dopamine, 3 to 18 gamma/kg/min; adrenaline, 0.2 to 0.7 gamma/kg/min; furosemide, 7 to 17 gamma/kg/min). The device was implanted through a midline sternotomy and under peripheral normothermic bypass. Five patients received a biventricular support, and one a single left prosthetic ventricle. The cannulation included a right-angled cannula in both the left and right atrium and a suture of the arterial Dacron tubes onto the ascending aorta and main pulmonary artery. After careful deairing of the tubing and ventricles, the console was activated and the bypass progressively discontinued. Heparin infusion was begun 3 hours after chest closure and was continued for the duration of assist pumping, which was 2 to 11 days (mean duration, 7.43 days). The system could provide a complete support of the circulation with both right and left ventricular index remaining stable at 2.4 to 3 L/min/m2. After a dramatic improvement at the time of the system activation, the urinary output remained adequate, thus allowing for a decreasing need for diuretic therapy. In two cases, including one of isolated left ventricular assist pumping, the circulation could be totally supported during 11 hours and 23 hours, respectively, of refractory ventricular tachycardia. Four of six patients were shortly weaned from inotropic agents. Hematologic studies showed a moderate decrease of the coagulation factors level during the first 6 hours of circulatory support, and this remained stable and within normal limits thereafter. There have been three cases of bleeding complications necessitating surgical revision on the sixth hour, the twelfth hour, and the sixth day, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)