Several observational and epidemiologic analyses suggest that moderate drin
king of alcohol (usually two drinks per day) may have beneficial effects on
the heart. Specifically it may reduce the incidence of ischemic heart dise
ase and improve the outcome after a myocardial infarction. The purpose of t
his study was to test the hypothesis that long-term, moderate consumption o
f alcohol has a direct cardioprotective effect, reducing myocardial infarct
size in rats subjected to ischemia/reperfusion. Two groups of rats were gi
ven alcohol in their drinking water at concentrations of 15% or 36%; contro
l rats received water (n = 10 for all groups). After 16 weeks of treatment,
the rats were anesthetized and subjected to 60 min of coronary artery occl
usion and reperfusion. The ischemic risk region (% LV) was not significantl
y different among groups. Infarct size (% risk zone) was 49 +/- 7%, 44 +/-
4%, and 50 +/- 8%, respectively (p = 0.79). Thus no significant differences
in infarct size between control and alcohol-fed rats were observed. There
was no correlation between alcohol level and infarct size in alcohol-treate
d rats (r = 0.20, p = 0.45). Arterial pressures were lower in the 36% group
at baseline and throughout the study compared with the control and 15% gro
ups, but heart rates were similar in all groups. Moderate consumption of al
cohol failed to alter infarct size compared with control and thus it is unl
ikely that alcohol drinking has a direct myocardial-protecting effect on th
e outcome of ischemia and reperfusion.