Objective: Noninvasive flow-mediated vasodilation (FMD) is a widely used method to assess endothelial function, but its technical difficulty and problems remain obstacles for use in clinical practice. Reactive hyperemia-peripheral arterial tonometry (RH-PAT) was developed as a simpler and more reproducible method. We compared FMD and RH-PAT in patients with stable angina. Furthermore, the differences in these two techniques according to coronary artery disease (CAD) severity and complexity were also assessed.
Materials and methods: We consecutively enrolled 80 patients who underwent elective coronary angiography. Endothelial function was assessed before angiography using brachial artery FMD and RH-PAT. The complexity and extent of the coronary lesions were assessed angiographically. The extent of CAD was defined as the number of diseased coronary arteries (>70%) and complexity of CAD was assessed by the SYNTAX score algorithm.
Results: In the overall study group (61±9 years, 57% men), the mean FMD was 8.5±5.1% and the mean reactive hyperemia index (RHI) measured by RH-PAT was 1.7±0.4. A significant correlation was observed between FMD and RHI irrespective of sex, diabetes, or presence of CAD. FMD and RHI were significantly lower in patients with multivessel and complex CAD. A receiver-operating characteristic curve analysis showed that both techniques were comparable in terms of predicting the presence of CAD and complexity.
Conclusion: Assessment of RH-PAT could be a less operator-dependent and noninvasive method of evaluating vascular endothelial function in patients with stable angina.
Department of Internal Medicine, Kyung Hee University Hospital, Cardiovascular Division, Kyung Hee University, Seoul, Republic of Korea
Correspondence to Weon Kim, MD, PhD, Department of Internal Medicine, School of Medicine, Division of Cardiology, Kyung Hee University, #1 Hoeki-Dong, Dongdaemoon-Gu, Seoul 130-702, Republic of Korea Tel: +82 2 958 8170; fax: +82 2 958 8160; e-mail: email@example.com
Received December 1, 2013
Received in revised form January 8, 2014
Accepted January 19, 2014