Intermittent coronary sinus occlusion in dogs: Reduction of infarct size 10 days after reperfusion

Intermittent balloon occlusion of the coronary sinus was applied to 11 open chest dogs subjected to 3 hours of ligation of the left anterior descending coronary artery followed by 8 to 12 days of reperfusion. Anticoagulants were not given during the reperfusion period. Risk region was assessed by planimetry of autoradiographs made from ventricular slices. Infarct size was equivalent when assessed by planimetry of ventricular slices before and after staining with triphenyltetrazolium chloride. In the seven survivors, 30 ± 8% of the risk region was in-farcted. Seven of 11 control dogs survived (p = NS); 75 ± 4% of the risk region was infarcted in the control animals (p < 0.01 versus treated survivors). Light microscopic inspection of specimens stained with hematox-ylin-eosin confirmed the border between necrotic and preserved myocardium. Thrombus was observed in the coronary sinus in all survivors in the treatment group. These findings confirm earlier short-term studies that demonstrated a potent anti-ischemic effect of intermittent coronary sinus occlusion. At the same time, coronary sinus thrombosis warrants caution in the application of this technique to myocardial ischemia in humans.