Detection and monitoring of asymptomatic atherosclerosis in clinical trials.

Methods are currently available to noninvasively detect and evaluate asymptomatic atherosclerosis in the carotid artery, and provide a unique opportunity to monitor the effect of medical intervention during the early stages of atherosclerotic progression. When using high-resolution B-mode ultrasound to monitor lesion change over time, it is the reproducibility of measurements at the arterial wall and lumen that defines the confidence of establishing rates of disease progression. Previous studies have demonstrated that, in a research environment using standardized protocols for scanning and interpretation, the absolute difference between blinded replicate measurements of arterial wall thicknesses at sites of lesion is less than 0.2 mm. The Multicenter Isradipine Diuretic Atherosclerosis Study will use high-resolution B-mode ultrasound to determine the effect of isradipine and hydrochlorothiazide on the rate of progression of carotid artery atherosclerosis in hypertensive subjects. Methods for scanning and interpretation of arterial wall thickenings are presented.