Association between Brachial Flow-Mediated Dilation and Calcium Score in Patients with Symptomatic CAD.

Background: Endothelial function plays an important role in the protection of vessels from atherosclerosis. Detection of endothelial dysfunction by non-invasive methods (flow-mediated dilation) and its association with other imaging modalities (calcium score in coronary computed tomography [CT] angiography) is still controversial. In this study, we aim to investigate the association between endothelial function evaluated by flow-mediated dilation (FMD) and calcium score evaluated by coronary CT.

Methods: In this cross-sectional study, 124 patients with known coronary artery disease (CAD, positive calcium score) were enrolled. FMD as an indicator of endothelial function was evaluated in these participants. FMD less than 7.1%was considered abnormal. Correlation between calcium score and severity of calcification(calcium score above 100 considered as the cutoff point of the high score) and glow-mediated dilation was obtained using the linear regression model.

Results: The association between calcium score and FMD was strongly significant (P < 0.001). Among individuals with low calcium scores, only 15 (18.1%) had abnormal FMD findings, but the majority of individuals with high calcium scores (95.1%) had abnormal FMD findings.

Conclusions: Our findings provide strong evidence of association between FMD, a marker of vascular endothelial dysfunction, and intensity of coronary atherosclerosis, as assessed by the calcium score on the CCTA.