Prolonged preservation of canine hearts followed by orthotopic heart transplantation
Kioka, Y.
Nihon Kyobu Geka Gakkai 34(12): 2082-2092
1986
ISSN/ISBN: 0369-4739 PMID: 3549928 Document Number: 273849
As the increase in heart transplantation successful techniques of the preservation are required for long distant donor heart transportation and histocompatibility tests. The purpose of this study is to compare the perfusion method with the immersion method for 24-hour heart preservation. Twenty-two canine hearts were rapidly excised after being flushed with 4.degree. C extracellular cardioplegic solution and were divided into 3 groups as follows; Group A: Seven hearts were orthotopically transplanted immediately after the excision. Group B: Seven hearts were transplanted after 24-hour immersion in nicardipine (1 mg/l) added to modified Collins' solution at 4.degree. C. Group C: Prior to transplantation eight hearts were perfused continuously with 4.degree. C oxygenated modified Collins' solution containing perfluorochemicals, nicradipine and albumin at a pressure of 15 mmHg for 24 hours. In Groups B and C, the ventricular pacing was discontinued when the heart rate reached 80/min. In all groups, two hours after the termination of cardiopulmonary bypass, hemodynamic studies and myocardial biopsies were performed. The mean perfusion flow of Group C remained constant for 15 hours and then gradually decreased. At the end of preservation, release of creatinine phosphokinase (p < 0.001) and lactate (p < 0.001) were significantly greater in Group B than those in Group C. All hearts started beating spontaneously but the time required between aortic declamping and resuming spontaneous contraction in Group B and C was longer than that in Group A with statistical significance (p < 0.001). One case in each of Group B and C was not weaned from the cardiopulmonary bypass. The others were able to maintain the recipient's circulation without any inotropic supports. There was no statistical difference between the post-transplanted hemodynamic indices (.+-. LV dp/dt Max., cardiac index, heart rate, stroke volume index, LV stroke work index) of the 3 groups. Electron microscopic examination revealed that the myocardial structures in Group A was almost normal. In Group B, there were intracellular edema, vacuolated sarcoplasmic reticulum and multifocal mitochondrial abnormalities, that is, swelling and disruption of cristae. In Group C, myocardial structural changes which were seen in Group B were not observed but pericapillary edema was present. This study suggested that the continuous oxygenated perfusion method for a prolonged period allowed preservation of the aerobic myocardial metabolism and that less ischemic damage was assured by enzyme leakage and ultrastructural assessment. As a method for prolonged preservation, the perfusion method was preferable to the immersion method.