This study examined if the use of simplified coronary sinus retroperfusion would lead to any reduction in the infarcted area associated with improved right and left ventricular function. Twelve mongrel dogs were entered in this study. Following anesthesia, a fast response thermistor was placed on the pulmonary artery via the jugular vein and aorta via the left ventricular apex. The left anterior descending artery (LAD) was separated from the vein, A retrograde cardioplegia catheter was inserted into the coronary sinus. Following these procedures, LAD was occluded for a period of 3.5 h. After 30 min ischemia, the aorta-coronary sinus connection was established. The animals were divided into two equal groups. One group was not treated and was considered the control group (six animals). In the remaining group (six animals), retroperfusion was used and was considered the retroperfusion group. At the end of the study, the left ventricular ejection fraction was 65+/-15% in the retroperfusion group and 48+/-5% in the control group (P < 0.05). The left ventricular stroke work index was 0.44+/-0.04 (g m/kg) in the retroperfusion group and 0.31+/-0.05 (g m/kg) in the control group (P < 0.05). Cardiac output was 1650+/-75 ml/min in the retroperfusion group and 1250+/-125 ml/min in the control group. The ratio of the infarct size to the area at risk was 49+/-5% in the control group and 7+/-3% in the retroperfusion group. In light of these studies, we conclude that simplified coronary sinus retroperfusion appears to be an effective method that must be taken into consideration. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.