Abstract 14050: Endothelial Function in Humans Using a Strain-Gauge Plethysmography is a Predictor of Cardiovascular Events

Abstract

Background: It is clinically important to estimate the degree of endothelial dysfunction. Several methods have been used to assess endothelial function in humans. The vascular response to the intra-arterial infusion of vasoactive agents should be considered the gold standard in assessing endothelial function. The purpose of this study was to evaluate the confounding factor for assessment of endothelial function using a strain-gauge plethysmography and whether endothelial function in forearm circulation is a predictor of future cardiovascular events.

Methods and Results: We have evaluated the effects of intra-arterial infusion of infusion of nitric oxide agonist, acetylcholine, on forearm blood flow using a strain-gauge plethysmography in 1218 subjects (796 men and 422 women; mean age, 51±16 yr), including cardiovascular diseases. Univariate regression analysis revealed that vascular response to acetylcholine correlated with basal blood flow (r=0.36, P<0.001), age (r=0.42, P<0.001), male sex (r=0.31, P<0.001), body mass index (BMI) (r=0.25, P<0.001), systolic blood pressure (r=0.37, P<0.001), diastolic blood pressure (r=0.27, P<0.001), low-density lipoprotein (LDL) cholesterol (r=0.19, P<0.001), high-density lipoprotein (HDL) cholesterol (r=-0.17, P<0.001), triglycerides (r=0.23, P<0.001), glucose (r=0.20, P<0.001), and smoking (r=0.28, P<0.001). Multivariate analysis revealed that basal blood flow, age, male sex, BMI, systolic blood pressure, HDL cholesterol, and smoking were independent predictors of vascular response to acetylcholine. Median follow-up period was 8.3 years. The 8-year cardiovascular event free survival rates were significantly greater in subjects with low vascular response to acetylcholine (n=609) than in subjects with high vascular response to acetylcholine (n=609) (0.76 vs. 0.92, P<0.001).

Conclusions: These findings suggest that basal blood flow, male sex, age, obesity, blood pressure, HDL cholesterol levels, and smoking habitus are confounding factors for measurement of vascular response to acetylcholine and that endothelial function in forearm circulation is a predictor of future cardiovascular events.