SIMPLIFIED RETROPERFUSION SYSTEM PRESERVES THE MYOCARDIAL-FUNCTION DURING ACUTE CORONARY-ARTERY OCCLUSION

It is known that coronary venous retroperfusion restores the blood flo w to the ischemic myocardium, resulting in reduction of infarct size a nd improvement in left-ventricular pump function. In this study, we us ed an animal model to investigate the effects of a simplified coronary venous retroperfusion system on myocardial hemodynamics. Twenty dogs were entered in this study. All dogs underwent fifteen minutes occlusi on of the left anterior descending artery. For the rest of the experim ent the dogs were randomized into two groups: the control group (n = 1 0) underwent a further 2 hours left anterior descending artery occlusi on, then clamps were released and the animals were observed for 6 hour s. In the retroperfusion group (n = 10) a simple aortocoronary sinus c onnection was made and retrograde perfusion achieved with an outflow o f 43 +/- 6 ml/min. Retrograde coronary sinus perfusion was maintained for three hours and then the dogs were observed for six hours. Tissue adenosine triphosphate levels were 6 +/- 3 mu mol/g in the control gro up and 12 +/- 2 mu mol/g in the retroperfusion group (p < 0.05) 6 hour s after reperfusion. Creatine phosphokinase levels were 99 +/- 11 IU/L in the control group and 42 +/- 8 IU/L in the retroperfusion group 6 hours after reperfusion (p < 0.05). Cardiac index was 63 +/- 4ml/kg/mi n in the control group and 79 +/- 2ml/kg/min in the retroperfusion gro up 6 hours after retroperfusion (p < 0.05). Left-ventricular stroke-wo rk index at a pulmonary capillary artery wedge pressure of 20 mmHg was 0.54 +/- 0.06 g.m/kg in the retroperfusion group and 0.29 +/- 0.03 g. m/kg in the control group 6 hours after reperfusion (p < 0.05). It is concluded that myocardial hemodynamic and biochemical function can be preserved by simplified coronary sinus retroperfusion.