The Relationship Between Ankle-Brachial Index and Number of Involved Coronaries in Patients with Stable Angina

BACKGROUND Atherosclerosis is the commonest cause of vascular disease which can involve peripheral and/or cardiac vessels. This study was conducted to evaluate the possible link between Ankle-Brachial Index (ABI) and coronary vessel involvement in patients with stable angina. METHODS This cross-sectional study was conducted in 2008 on 120 individuals who were hospitalized in Chamran Heart Center and underwent coronary angiography. A questionnaire was completed to obtain demographic information, history of previous heart disease and smoking. Body height and weight, as blood pressure on hand and foot were measured. The patients underwent angiography and the extent of coronary involvement (> 75%) was determined. After12-14-hour of fasting, blood sugar was obtained to measure total cholesterol, triglyceride, low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). The Ankle Brachial Pressure Index (ABI) was calculated as the ratio of the blood pressure in the ankles to the blood pressure in the arms. The data were analyzed by SPSS-15 using ANOVA, T-Student test, Spearman's rank correlation coefficient, and discriminant analysis. RESULTS Samples were 46 women (38.33%) and 74 men (61.67%) with a mean age of 55.50 ± 10.49. Mean and SD of ABI in men and women was 0.72 ± 0.20 and 0.80 ± 0.19 with no significant difference (P=0.012). The correlation between ABI and extent of coronary involvement was 0.47 (P < 0.0001). The group with lower ABI had the highest levels of coronary involvement (triple vessel, P < 0.05). CONCLUSION ABI had a significant relationship with the degree of coronary involvement and a significant predictive value. Therefore ABI seems to be a reliable indicator of high coronary risk.