In two studies on the same group of patients we evaluated noninvasive methods of assessing
atherosclerosis and determined the effect of the new
calcium channel-blocking agent
monatepil on the progression of early
atherosclerosis in humans. Computed tomography (CT) of the lower abdominal aorta and ultrasonography of the carotid arteries were used as noninvasive methods to determine the extent of
atherosclerosis. To evaluate the CT images, we developed a new medical image analysis program. This enabled aortic calcification volume (ACV) to be quantified using plain CT images, and aortic wall volume (AWV) and aortic wall and calcification volume (AWCV) to be quantified from contrast CT images. Interobserver coefficients of variation of ACV, AWV, and AWCV (n = 8) were 4.7, 2.4, and 5.0%, respectively. In the
monatepil study, the effect of the
drug on serum
lipid profiles was evaluated. Preliminary results show that shortly after
monatepil administration, total serum
cholesterol levels decreased significantly from 253.8 +/- 35.6 to 244.8 +/- 38.6 mg/dL (P < .009) and
triglyceride levels tended to decrease. A positive correlation between the change in total
cholesterol and changes in mean platelet volume was found (P = .028). Fasting immunoreactive
insulin levels decreased in the four patients in which they were determined. Although this is a preliminary study, results indicate that CT of the lower abdominal aorta in combination with our new analysis program may be a precise, reproducible means of assessing early
atherosclerosis. We have also shown that
monatepil significantly decreases total
cholesterol levels. However, the long-term effects of
monatepil on the progression of
atherosclerosis remain to be determined.