The combined effects of brain death and cardiac graft preservation on cardiopulmonary hemodynamics and function before and after subsequent heart transplantation.

BACKGROUND: The combined effects of brain death and graft preservation on right and left ventricular function and on pulmonary hemodynamics after subsequent heart transplantation have not been previously studied. METHODS: Fifty-seven dogs (25.5 +/- 0.3 kg) were divided into three groups and underwent a total of 20 brain death experiments and 16 orthotopic complete atrioventricular transplantations with the use of a validated brain death organ donor model, hypothermic heart preservation, and right and left ventricular functional analysis (preload-independent recruitable stroke work, Fourier analysis). In the first group, changes in cardiopulmonary function were assessed over a period of 6 to 7 hours after brain death. In the second group, the hearts were procured from a donor with brain death and immediately transplanted whereas in the third group cardiac graft preservation for a period of 4 hours followed harvest from a donor with brain death before heart transplantation and assessment of heart transplant function. RESULTS: After brain death alone, a significant increase in right and left ventricular end-diastolic pressures and a decrease in systemic and pulmonary resistance and pulmonary impedance occurred. Furthermore, right and left ventricular function decreased significantly by 35% and 19%, respectively, and subsequent transplantation did not cause further cardiac dysfunction. Preservation in combination with brain death led to further significant decreases in right ventricular function after subsequent transplantation compared with brain death alone, necessitating the use of dopamine to wean four animals from cardiopulmonary bypass. CONCLUSION: Brain death causes a significant loss of right and left ventricular function. These injuries are greater in the right ventricle and may contribute to early right ventricular failure after transplantation. Brain death and cardiac graft preservation have significantly additive deleterious effects on right ventricular function after transplantation.

Duke Scholars

Author Edward Po-Chung Chen Surgery, Cardiovascular and Thoracic Surgery