Preservation of myocardial metabolism in acute coronary artery occlusions with retrograde coronary sinus perfusion and iloprost

Abstract

A total of 12 healthy mongrel dogs were subjected to the study. The left anterior descending artery was occluded. The occlusion was done for 15 min. At the end of this period, without removing the occlusion, the heart was retroperfused for 3 h. Then, occlusion was removed and reperfusion was supplied. Animals were divided into two equal groups. Six animals received iloprost and the other six control did not receive any additional treatment. In the iloprost group, the drug was administered into the coronary sinus. After 15 min following occlusion, iloprost was infused at a rate of 50 μg/min continuously. Cardiac output (CO), mean arterial pressure (MAP), mean pulmonary arterial pressure (MPAP), heart rate (HR), pulmonary capillary wedge pressure (PCWP), right atrium pressure (RAP), myocardial oxygen extraction (MOE) and myocardial lactate extraction (MLE) parameters were examined in the two groups, before and during retroperfusion and during the reperfusion (1–4 h). Iloprost retroperfusion (50 μg/min) was started at the fifteenth minute of occlusion and continued till the end of the observation period (3 h). The measured hemodynamic data showed that the hearts treated with iloprost had satisfactory preservation of cardiac function. At the end of the reperfusion period cardiac output was 1.5 ± 0.06 L/min in the control and 1.7 ± 0.04 L/min in the iloprost group ( P < 0.05). At the end of the reperfusion period, tumor necrosis factor level was raised significantly in the control group ( P < 0.05). Myocardial lactate release was also high in the control group ( P < 0.05). CPK-MB release was low in the iloprost group ( P < 0.05). We conclude that retrogradely administered iloprost reduced the risk of myocardial injury and it is probable that this drug effectively distributes to the area of myocardium at risk.