Secular trends in coronary atherosclerosis - Analysis in patients with valvular regurgitation

Background: Between 1980 and 1989, mortality due to coronary artery disease decreased considerably in the United States, suggesting a possible decrease in the prevalence of coronary atherosclerosis. We examined this possibility in patients with valvular regurgitation who, often in the absence of angina, underwent coronary angiography before valve-replacement surgery. Methods: We studied 601 patients with isolated, nonischemic valvular regurgitation who were operated on between 1980 and 1989 and who had undergone preoperative coronary angiography. From the angiograms we determined the prevalence of clinically significant coronary artery disease and of multivessel disease, assessed the mean degree of stenosis, and analyzed the trends in the data over the years of the study. Results: The prevalence of coronary artery disease (35 percent in 1980-1981, 37 percent in 1982-1983, 34 percent in 1984-1985, 37 percent in 1986-1987, and 35 percent in 1988-1989; P=0.97) did not change significantly during the study period. We found no significant change in the prevalence of multivessel disease (24 percent in 1980-1981 and 23 percent in 1988-1989, P=0.99) or in the mean (±SD) degree of stenosis (11±13 percent in 1980-1981 and 13±14 percent in 1988-1989, P=0.07). When these measures of coronary atherosclerosis were adjusted for age and sex, there were still no significant changes over time (P=0.39 for the prevalence of coronary artery disease, P=0.81 for that of multivessel disease, and P=0.57 for the mean degree of stenosis). The patients' mean total cholesterol level decreased from 219±48 mg per deciliter (5.66±1.24 mmol per liter) to 206±44 mg per deciliter (5.33±1.14 mmol per liter) between 1980 and 1989 (P=0.04). Conclusions: From 1980 to 1989, no significant change was observed in angiographic measures of coronary atherosclerosis in patients with nonischemic valvular regurgitation, in contrast to the marked decrease in mortality due to coronary disease in the general population. These findings suggest that the well documented reduction in mortality due to coronary disease may not be due to a reduction in the prevalence of coronary atherosclerosis.