Influence of Serum Cholesterol and Cholesterol Subfractions on Restenosis After Successful Coronary Angioplast A Quantitative Angiographic Analysis of 3336 Lesions

Background Previous reports have suggested that hyperlipidemia may be associated with increased restenosis after successful coronary angioplasty. These studies have been compromised, however, by their retrospective nature, the small numbers involved, differences in the definition of restenosis, and inadequate quantitative angiographic follow-up at a prespecified time interval. The objective of the study was to examine the relation between serum cholesterol and long-term restenosis after coronary angioplasty, using quantitative angiography, at a predetermined time interval. Methods and Results The study population comprised 2753 patients (3336 lesions) prospectively enrolled and successfully completing four major restenosis trials. Cineangiographic films were processed and analyzed at a central angiographic core laboratory with the use of an automated interpolated edgedetection technique. Serum total cholesterol was measured at trial entry and at 6 months. Hypercholesterolemia was defined as total cholesterol >7.8 mmol . L` at trial entry. Two approaches were used to assess restenosis: first, a categorical approach using the cutoff point of >50% diameter stenosis at follow-up and second, a continuous approach examining changes in minimal luminal dimensions, the absolute loss (change in minimum luminal diameter after PTCA to followup, in mm) and relative loss (absolute loss corrected for vessel size), which may give a better understanding of the underlying pathological process involved. One hundred sixty patients with 191 lesions (5.73%) had hypercholesterolemia (total cholesterol, >7.8 mmol . L-; mean+SD, 8.46±0.75 mmol * L-l) and