786-5 Risk Factor Modification Improves Flow-Mediated Brachial Artery Vasoactivity but not Cold Pressor Vasoactivity in Men with Coronary Artery Disease

Coronary risk factors are associated with impaired endothelium-mediated vasoactivity in the peripheral and coronary circulation. To determine the effect of risk factor modification (RFM) on brachial artery vasoactivity, we studied 23 men with coronary artery disease (CAD). Using 7.5MHz ultrasound, brachial artery diameter changes (%Δ Diam) in response to flow mediated (FM) and cold pressor (CP) stimuli were measured in 13 men 1 week after the initial presentation of ischemic heart disease and in another 10 men 1 year after aggressive risk factor modification, (smoking cessation, lipid lowering).Chronically managed patients had significantly lower total cholesterol and smoking frequency.Acute vs.Chronic CADAge (yrs):4646Chol(mg/dl):219171*HDL(mg/dl):3632Smoking:63%6%*BP(mmHg):123/71130/80FM (% Δ Diam):4.8%10.9*CP (% Δ Diam):-2.4%-2.3%*p<0.01FM vasoactivity normalized with risk factor modification and was similar to our controls 11.5±7.0%. CP response remained abnormal despite chronic RFM. This suggests that FM vasoactivity is dependent on risk factor status, but CP vasoactivity may be dependent on the presence of CAD