Abstract 13580: Effect of Angiotensin Receptor Blockade on the Coronary Plaque Component in Patients With Stable Angina: Virtual Histology Intravascular Ultrasound Study
Background: The renin-angiotensin system is associated with the pathogenesis of atherosclerosis. Angiotensin II type 1 receptor blockers (ARB) inhibit the rennin-angiotensin system. However, the effect of ARB on coronary atherosclerosis has not been clarified. [Purpose] We investigated the effects of ARB on the coronary plaque component in stable angina patients using virtual histology intravascular ultrasound (VH-IVUS). [Method] Four hundred and eighty-two consecutive patients with stable angina who underwent coronary stent implantation after VH-IVUS were enrolled in this study. The patients were divided into two groups; patients treated with ARB (ARB group, n=177) and without ARB (non-ARB group, n=305). The ARB was administered for at least 6 months. The patients who were treated with both ARB and angiotensin converting enzyme inhibitors were excluded. The baseline patient characteristics (age, gender, diabetes mellitus, hypertension, current smoke, LDL-cholesterol, HDL-cholesterol, proportion of treated with statins) and VH-IVUS analysis of the culprit lesions were compared between the two groups. The coronary plaque histological composition was classified as fibrous, fibro-fatty (FF), dense-calcium and necrotic core (NC) by VH-IVUS. Furthermore, the predictors for the FF and NC ratios were assessed using multivariate logistic regression analysis.
Results: The age (70±9y.o vs. 68±10y.o, p=0.01) and proportion of hypertension (81% vs. 59%, p<0.0001) were higher in the ARB group. The FF ratio (9±8% vs. 12±10%, p=0.02) was lower, but the NC ratio (23±11% vs. 20±12%, p=0.02) was higher in the ARB group, compared with the non-ARB group. The other parameters were not different between the two groups. In the multivariate analysis, ARB (odds ratio 1.6, 95% confidence interval 1.0–2.4, p=0.03), female gender (p=0.006) and diabetes mellitus (p=0.008) were independent predictors for FF≤9%. On the other hand, ARB was not a predictor, but only diabetes mellitus (p=0.007) was a predictor for NC≥23%. These results suggest that ARB may reduce the FF component in the culprit coronary plaque. [Conclusion] ARB may influence the coronary plaque component in stable angina patients.
- © 2010 by American Heart Association, Inc.