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Background: In this report we describe the in vivo evaluation of a device and ventriculocoronary artery bypass procedure that creates a permanent transmyocardial channel between the left ventricle and a coronary artery., Methods: The transmyocardial device, an L-shaped titanium tube with a meshed distal tip and an exterior polyester cuff, was implanted from the base of the left ventricle to the proximal left anterior descending coronary artery in 11 healthy juvenile domestic pigs using a beating-heart approach. Flow rates were measured at implant. Patency was assessed at explant for surviving animals at 2 (n = 3) and 4 weeks (n = 4)., Results: Flow through the transmyocardial device after implantation was 74% of base line. Forward flow occurred during systole. Luminal patency was 100% at 2 weeks and 75% at 4 weeks. Histologic analysis showed little to no intimal proliferation at the coronary interface., Conclusions: This short-duration study shows promise for perfusing ischemic myocardium with systolic flow. The transmyocardial titanium conduit and treated coronary artery patency was good at 2 and 4 weeks and warrants further studies.

Background: The data presented are a brief summary of The International Registry for Mechanical Ventricular Assist Pumps and Artificial Hearts and a summary of the personal experience of the Minnesota Thoracic Associates at the Minneapolis Heart Institute with the use of the Sams centrifugal pump from May 1985 to September 1994., Methods: Ventricular support with the use of centrifugal pumps for postcardiotomy shock consisted of cannulation of the left atrium and aorta for left ventricular support and the right atrium and pulmonary artery for right ventricular support, or the combination of the two for biventricular support., Results: The average survival and discharge rate recorded by the National Registry for postcardiotomy syndrome was 25.3%. Our experience at Minnesota Thoracic Associates was 54%. The National Registry reported 45.7% of the patients being weaned from the device or receiving transplants and 25.3% of the patients ultimately discharged from the hospital. Sixty-five percent of the patients in our experience either were weaned from the device or received a transplant for an overall discharge rate of 42%. The average effective hospital cost per survivor was almost $400,000.00., Conclusions: It is our belief that when considering the cost analysis of temporary devices, one must conclude that a more economical approach for the treatment of end-stage cardiac disease would be aggressive development of a permanent ventricular assist device.

From October 1985 through December 1989, 92 heart transplant procedures were performed in 89 patients. Nine patients (aged 19 to 66 years; 7 male, 2 female) required mechanical circulatory support after transplantation because of primary idiopathic organ failure (n = 2), implant difficulty (2), poor organ quality (2), or acute right heart failure (3). Devices used included the intraaortic balloon pump (6), centrifugal right ventricular assist device (2), left ventricular assist (1), biventricular assists (2), and total artificial heart (1). Two patients required multiple devices. One patient underwent retransplantation. Implant time ranged from 1 to 18 days. One early death occurred owing to right heart failure 6 days after transplantation, 7 hours after removal of a right ventricular assist device, for an overall mortality of 11%. The remaining 8 patients are alive 4 months to 28 months after transplantation. The actuarial 1-year survival of 89% +/- 10% compares well with the survival of 87% +/- 4% for the entire transplant group. All surviving patients are in functional class I. Echocardiographic examination in all patients revealed left ventricular ejection fraction to be normal in 7 and depressed in 1. Extending the criteria for organ donors or difficulty with the implant procedure can lead to early organ failure, which may be reversible with circulatory assistance allowing excellent survival.