Does therapeutic intervention achieve slowing of progression or bona fide regression of atherosclerotic lesions?

This review focuses on the regression of atherosclerosis in humans and expe rimental animals. It highlights the difficulties to determine unequivocally whether with a given therapeutic intervention, such as diet, drugs, or aph eresis, the progression of lesions was curtailed or bona fide regression of atherosclerotic lesions was achieved. It seems appropriate to mention that 2 very different ways to measure regression were used in experimental anim als and in humans. Regression in animals was determined mainly in the aorta or coronary arteries isolated at post mortem, and the criteria used were d egree of sudanophilia and/or aortic wall thickness and cellular composition or cholesterol content. In humans, the evaluation of regression relied mai nly on quantitative coronary angiography. The literature of the past decade is reviewed selectively but not exhaustively, and in some instances, a bri ef historical overview is given.