Increased ambulatory pulse pressure is a strong risk factor for coronary endothelial vasomotor dysfunction

This study was aimed to determine the relationship between pulse pressure (PP) and coronary vasomotor dysfunction, a predictor of coronary events. Pulse pressure is a strong risk factor for coronary artery disease (CAD). However, the mechanisms by which an increase in PP affiects the pathogenesis of CAD are unclear. Ambulatory blood pressure (13P) monitoring for 24 h was performed in 103 consecutive patients with normal coronary angiograms (51 hypertensive and 52 normotensive; age 42 to 70 years). The relationship between changes in coronary arterial diameter and blood flow during an intracoronary infusion of acetylcholine (ACh) (5, 10, 50 mu g/min), and BP parameters, and other traditional risk factors was evaluated using univariate and multivariate linear regression analyses. With multivariate analyses, the 24-h PP showed an inverse correlation with the epicardial coronary dilator response to ACh independently of other covariates including age, smoking, and 24-h systolic BP in normotensive as well as hypertensive patients. Furthermore, multivariate analysis showed that the 24-h PP was inversely and independently correlated with the increase in coronary blood flow in response to ACh. The dilator response of epicardial coronary arteries to nitrate was not significantly correlated with 24-h PP. Increased 24-h PP is independently associated with endothelial vasomotor dysfunction in conduit and resistance coronary arteries irrespective of the presence of hypertension. Increased ambulatory PP may have an intimate relation to coronary endothelial vasomotor dysfiinction. (c) 2005 by the American College of Cardiology Foundation.