Application of th Total Artificial Heart as an Implantable Biventricular Assist Device by Left Thoracotomy in an Ovine Model / 대한흉부외과학회지

ABSTRACT

BACKGROUND: The purpose of this study was to investigate the possibility of using the moving-actuator type total artificial heart as a biventricular assist device(BVAD) and to establish a safe and effective animal model for the implantation of a BVAD. MATERIAL AND METHOD: Seven Corridale sheep were used in this study wherein left thoracotomy was performed. The left and right outflow cannulas were anastomosed to the descending thoracic aorta and the main pulmonary artery, and the left and right inflow cannulas were inserted to the left atrium and the right atrial appendage. The devices were positioned in the preperitoneal pocket in 4 sheep, in the left pleural cavity in 2 sheep, and externally in 1 sheep. The aPTT was maintained between the 2 and 2.5 times the range that of the baseline. RESULT: Cannulation was carried out successfully in all cases. There was no case of operative death or immediate postoperative death. Three sheep expired postoperatively on the 2nd day because of thromboembolism, an artificial ventilator accident, and device and respiratory failure. Three other sheep died postoperatively on the 4th day because of acute renal and respiratory failure following thromboembolism. One sheep survived for 28 days. Experimentation on this animal terminated due to an electrical short-circuit caused by motor wire erosion. Thrombi were found on the valves of 4 out of 7 animals, especially on the connection between valves and the device. However , there was no thrombus in the cannulas. CONCLUSION: In conclusion, left thoracotomy for insertion of 4 cannulas and placement of device in the preperitoneal space is the safe and effective operative technique in ovine for testing in-vivo biocompatibility of the BVAD. Furthermore, it may be possible to use a moving-actuator type total artificial heart as a BVAD if technical improvements for reducing thromboembolism are carried out.