Assessment of cardio-ankle vascular index in patients with cardiac syndrome-X: an observational study

Objective: Arterial stiffness is associated with major adverse cardiovascular events. Cardio-ankle vascular index (CAVI), a novel marker of arterial stiffness, which is weakly influenced by systolic blood pressure, is a sensitive marker the atherosclerosis and arteriolosclerosis. The aim of this study is to investigate arterial stiffness by CAVI in patients with cardiac syndrome X (CSX). Methods: The present study was observational and cross sectional, and involved 49 patients (26 male) with CSX (angina-like chest pain, positive electrocardiographic ischemic changes at treadmill exercise test, angiographically normal coronary arteries) and 54 healthy subjects (21 male). CAVI was measured by VaSera-1000 CAVI instrument. Statistical analysis was performed using the Chi-square, Student t-test, correlation analysis and logistic regression analysis. Results: The CAVI and pulse pressure were significantly increased in patients with CSX compared to control group (7.50 +/- 1.50, 6.49 +/- 0.77, p<0.001; 53.00 +/- 10.06, 47.39 +/- 8.17, p=0.002, consecutively). In contrast, there were no significant differences in the age, weight, height, body mass index, waist circumference, hip circumference, systolic blood pressure, diastolic blood pressure, mean blood pressure, glucose, low density lipoprotein level, high density lipoprotein level (HDL), triglyceride, estimated creatinine clearance, hemoglobin, left atrium diameter, left ventricular mass (LVM), LVM index and ejection fraction. CAVI was the only independent predictor of CSX in logistic regression analysis (OR=1.780, 95% CI: 1.157-2.737, p=0.009). Conclusion: CAVI is increased in syndrome X patients and is an independent predictor of this syndrome.