Association of endothelial function and limb artery indices with coronary artery stenosis severity in patients with hypertension.

Background: Hypertension is one of the major risk factors for cardiovascular events. This study aims to analyse the association of endothelial function and limb artery indices with coronary artery stenosis (CAS) severity in hypertension based on easily accessible and detailed clinical information, and to help accurately identify high-risk groups and avoid missed diagnosis and misdiagnosis.
Methods: Admission data of 1,375 consecutive hypertensive patients complicated with suspected coronary atherosclerotic heart disease (CHD) from September 2020 to August 2021 in China-Japan Friendship Hospital were retrospectively assessed. All candidates underwent coronary angiography for screening. A total of 600 eligible patients were classified in the CHD group ( n  = 359) and non-CHD group ( n  = 241) based on their coronary angiography results. Subjects in the CHD group were further assigned to 'high stenosis' ( n  = 178) and 'low stenosis' ( n  = 181) subgroups based on the median value of Gensini score. Endothelial function and limb artery indicators, including brachial artery flow-mediated vasodilatation (FMD), ankle-brachial index (ABI) and brachial-ankle pulse velocity (baPWV), were examined and compared between subgroups. Multivariate logistic regression analysis and multiple linear regression analysis were carried out to select independent risk factors of CAS severity in hypertension. A predictive equation was conducted according to the results of multivariate logistic regression analysis to make clinical practice easier. As the receiver operating characteristic (ROC) curve had been plotted, the predictive ability of endothelial function and limb artery indicators in CAS severity in hypertension was detected by the area under the curve (AUC).
Results: In patients with hypertension, the FMD ( p  = 0.023), ABI ( p  < 0.001) and baPWV ( p  < 0.001) of CHD patients appeared substantially different from the non-CHD patients. Furthermore, the ABI ( p  < 0.001) and baPWV ( p  = 0.032) both independently associated with CAS severity in hypertensive patients with CHD. Based on the results of multivariate logistic regression analysis with CAS severity as a dependent variable, a predictive equation of baPWV, ABI and FMD was developed: combined coefficient = Logit( p )=5.531-0.218*FMD-7.019*ABI + 0.244*baPWV. From the combined coefficients of baPWV, ABI and FMD, the largest AUC was 0.800, suggesting a powerful predictive value of CAS severity in hypertensive patients, followed by ABI (AUC = 0.747, 95%CI 0.693-0.796), baPWV (AUC = 0.704, 95%CI 0.648-0.756) and FMD (AUC = 0.588, 95%CI 0.529-0.645).
Conclusion: This study shows that baPWV, ABI and FMD are independent risk factors for CHD, of which, baPWV and ABI are strongly associated with CAS severity in hypertensive patients. The predictive ability of CHD in hypertensive patients may be enhanced through combining the three endothelial function and limb artery indicators. The results may help to facilitate clinical decision-making during treatment and management of coronary artery disease.