LIMITATIONS OF ANGIOGRAPHY FOR ANALYZING CORONARY ATHEROSCLEROSIS PROGRESSION OR REGRESSION

Purpose: To analyze the utility and limitations of serial coronary angiography for determining atherosclerosis progression and regression. Data Sources: A MEDLINE search of the English-language literature (1966 to January 1994) using the keywords atherosclerosis regression, atherosclerosis progression, lipid reduction therapy, and coronary angiography. Study Selection: Selected articles on the effects of cholesterol reduction and lifestyle modification on angiographic coronary artery disease, on the animal models of atherosclerosis progression and regression, and on the limitations of coronary angiography. Data Extraction: Independent extraction by two authors. Results: Although several studies have reported that the rate of atherosclerosis progression, defined by serial coronary angiography, can be reduced and that luminal diameter can be improved somewhat by aggressive lipid modification, the reported changes are small (0.3 mm or 10% change) and have required a prolonged study duration (range, 1 to 10 years). More importantly, angiography simply does not measure atherosclerosis and cannot assess lesion composition. Angiography also underestimates the extent of atherosclerosis, especially in angiographically normal segments. In addition, difficulties with data acquisition, such as substantial variabilities in serial measurements of percent diameter stenosis and minimal luminal diameters, require large sample sizes to show statistically significant regression, even with computerized quantification. Conclusions: Given its current limitations, serial coronary angiography is not a satisfactory means of detecting atherosclerosis progression or regression.