Background and purpose: Flow-mediated dilatation (FMD) measurement in brachial artery (BA) is a method of assessing endothelial cell function and predicting atherosclerotic coronary artery disease. We investigated the predictive value of FMD for the presence of coronary artery disease (CAD) in a low-risk group of patients.

Materials and methods: A prospective study was performed in 397 patients (mean age 53.2±9 years including 194 men) with chest pain who were admitted for coronary angiography. FMD was measured in the BA before coronary angiography using two-D high-resolution ultrasound. SPSS V.17 was used for data analysis.

Results: Coronary angiography was normal in 151 patients but single vessel coronary artery disease (SVD) and multi-vessel coronary artery disease (MVD) were found in149 and 97, respectively. FMD was significantly higher in individuals with normal coronary arteries compared to those with coronary artery disease (11.1±2.5% vs. 6.8±3.1%; P<0.001). Patients with MVD showed lower FMD than those with SVD (4.2±2.2% vs. 8.6±2.2%; P<0.001). Logistic regression analysis showed that impaired FMD was independently associated with the presence of CAD (R= 0.74; P<0.001). The area under curve for FMD was 0.86 (95% CI 0.83-0.9; P<0.001).

Conclusion: Endothelial cell produces nitric oxide (NO) which plays a major role in vascular physiology. Measurement of NO is not possible, therefore, endothelial cell function is measured indirectly using FMD. According to this study FMD is suggested as an acceptable diagnostic tool to predict arteriosclerosis in low risk patients particularly when screening is conducted among this population.