[Extended hypothermic heart-lung preservation system for cardiopulmonary preservation with retrograde coronary sinus perfusion and lung immersion].

One major restriction of clinical heart-lung transplantation has been the inability to provide extended hypothermic organ preservation. We examined whether core-cooling, retrograde heart perfusion and lung immersion could provide adequate cardiopulmonary preservation. Hence, donor dogs were placed on cardiopulmonary bypass, and rapidly cooled to 15 degrees C. Then heterotopic heart unilateral left lung transplantations were performed. In control group I (n = 5), hearts and lungs were harvested following core-cooling and cardioplegic arrest, and transplanted immediately. In experimental group II (n = 5), heart-lung blocks were similarly excised but stored at 4 degrees C for 12 hours and then transplanted. During preservation, the lungs were immersed in the extracellular solution. For the heart, non-recirculating retrograde coronary sinus perfusion was performed with oxygenated intracellular solution containing perfluorochemicals. Myocardial function determined by the ratio of end-systolic pressure to end-systolic dimension in the experimental group was similar to that in controls. Although pulmonary vascular resistance and extravascular lung water of the experimental group was higher than those in control group, arterial oxygenation was similar in both groups. Thus, extended heart-lung preservation with core-cooling, retrograde heart perfusion and lung immersion technique could be achieved for heart-lung transplantation.