Intermittent coronary sinus occlusion after coronary arterial ligation results in venous retroperfusion.

Coronary sinus occlusion retards necrosis of ischemic myocardium. To test the hypothesis that coronary sinus occlusion induces retrograde venoarterial flow, the coronary arteriovenous pressure gradient and the coronary arterial oxygen saturation were measured distal to a left anterior descending coronary artery ligature in dogs. In parallel, we constructed a mathematical model of known coronary physiology to characterize pressure and flow patterns during coronary sinus occlusion. In dogs, coronary sinus occlusion produced a systolic pressure gradient between the coronary artery and the coronary sinus of -20 +/- 9 mm Hg (higher venous pressure, p less than 0.0001) and a positive diastolic gradient of 3 +/- 5 mm Hg (lower venous pressure p less than 0.01). An average reduction in the oxygen saturation in the ligated coronary artery of 20 +/- 13% was also observed (p less than 0.005) consequent to admixture of venous (desaturated) blood. By graded inflation of the coronary sinus balloon, it was demonstrated ...