Noninvasive Investigation of the Presence and Extent of Coronary Artery Disease by the Evaluation of Fingertip-Reactive Hyperemia

Objective: Fingertip-reactive hyperemia-peripheral artery tonometry (RH-PAT) is an emerging novel noninvasive method for evaluating endothelial function. We aimed to evaluate endothelial function with fingertip-reactive hyperemia by RH-PAT in symptomatic patients undergoing elective coronary angiography and to assess the relationship between the degree of endothelial dysfunction (ED) and the presence and the severity of coronary artery disease (CAD). Subjects and Methods: We assessed 92 patients. Before coronary angiography, endothelial function was measured by RH-PAT and reactive hyperemia index (RHI) was obtained. For each patient, the Gensini score was calculated according to the coronary angiographic findings to evaluate the severity of CAD. Results: In CAD (+) group, RHI (1.35 +/- 0.57 vs. 1.74 +/- 0.46, p = 0.001) mean values were lower than CAD (-) group. In multivariate logistic regression analysis, age, high-density lipoprotein, and RHI were found to be independent parameters predicting the presence of CAD. In multivariate linear regression analysis, RHI was found to be an independent predictor associated with the severity of CAD. In receiver operating characteristic curve analysis, RHI achieved an area under the curve of 0.763 (95% confidence interval 0.663-0.846, p = 0.001) for the ability to predict the presence of CAD. A cut-off value of 1.49 for an RHI predicted the presence of CAD with a sensitivity of 75% and a specificity of 72.9%. Conclusion: RH-PAT is an objective and highly reproducible test with superior diagnostic accuracy for the evaluation of ED. We found significant correlations between ED and the presence and the severity of CAD.