The influence of non-coronary collateral blood supply on the electively arrested heart during ischemia and reperfusion

To study the influence of non-coronary collateral blood circulation (NCCBC) on the integrity of the ischemic myocardium a right-sided thoracotomy was performed on 15 anesthetized dogs. Following a total cardiopulmonary bypass (CPB), ventricular fibrillation was induced, during which 2,000 ml calcium-free cardioplegic solution LK 352 was given at the aortic root over an 8–10-min period. Precautions were taken to prevent retrograde blood flow into the coronary system via the coronary sinus. After 90 min of ischemia, ten of the dog hearts were reperfused with systemic blood for the next 30 min. Transmural biopsies were taken from the apex of the left ventricle at the following intervals: (1) before CPB, (2) immediately after the infusion of LK 352, (3) following 90 min of ischemia, (4) after 5 min, (5) after 15 min, and finally (6) after 30 min of reperfusion and were then studied ultrastructurally. The presence of NCCBC was documented by the observation of erythrocyte-filled blood vessels in the biopsies corresponding to nos. 2 and 3 of the above.