EFFECT OF ETHANOL ON MYOCARDIAL INFARCT SIZE IN A CANINE MODEL OF CORONARY-ARTERY OCCLUSION-REPERFUSION

This study was conducted to determine if elevated blood alcohol prior to acute coronary artery occlusion affects myocardial infarct size in an in vivo canine model. Seven pentobarbital anesthetized open-chest d ogs received 10 min iv infusion of ethanol (0.08 g/kg/min). Ten min af ter ethanol, the left anterior descending coronary artery (LAD) was oc cluded distal to its first major branch for 60 min. The LAD was then r eperfused for 5 h. Following electrically induced ventricular fibrilla tion, the area at risk of infarction was delineated with dye. The area of infarction was identified by staining with triphenyl tetrazolium c hloride. Eleven untreated control experiments were also conducted. Mea n blood ethanol concentration was 155 +/- 26 mg/dl just prior to LAD o cclusion and 47 +/- 3 mg/dl after 4 h reperfusion. Ethanol infusion ha d no effect on systemic hemodynamic variables during ischemia. In etha nol treated animals, the area at risk was 19.7 +/- 3.0% of the left ve ntricle, and the infarct size was 20.9 +/- 4.8% of the area at risk. I n control experiments, the area at risk was 23.0 +/- 4.1% Of the left ventricle (p > 0.05), and the infarct size was 21.6 +/- 3.8% of the ar ea at risk (p > 0.05). Collateral blood flow to ischemic region did no t differ between the two groups, and the relationships between infarct size and collateral flow were similar for control and untreated heart s. Acute ethanol exposure prior to coronary artery occlusion and subse quent reperfusion does not affect myocardial infarct size in the heart of the anesthetized dog.