The effect of aggressive and moderate lowering of LDL-cholesterol and low dose anticoagulation on plasma lipids, apolipoproteins and lipoprotein families in post coronary artery bypass graft trial

The reported results (The Post Coronary Artery Bypass Graft Trial Investiga tors. The effect of aggressive lowering of low-density lipoprotein choleste rol levels and low-dose anticoagulation on obstructive changes in saphenous -vein coronary-artery bypass grafts. New Engl J Med 1997;336:153-162) of th e Post Coronary Artery Bypass Graft (Post CABG) trial have shown that aggre ssive lowering was more effective than moderate lowering of low density lip oprotein (LDL) cholesterol in reducing the progression of atherosclerosis i n saphenous-vein grafts (27 vs. 39%; P < 0.001); low dose warfarin had no e ffect on the progression of atherosclerosis. The present report describes t he effect of long-term (an average of 4.3 years) aggressive treatment with high (40-80 mg/day) and moderate treatment with low (2.5-5 mg/day) doses of lovastatin on lipids, apolipoproteins (apo) and apoA-and apoB-containing l ipoprotein families. To achieve the target LDL-cholesterol levels (60-85 mg /dl for aggressive group and 134-140 mg/dl for moderate group), cholestyram ine (8 g/day) was given to 25% of subjects on aggressive and 5% of subjects on moderate treatment. Although with both treatment strategies there were significant decreases (P < 0.001) in the levels of total cholesterol, LDL-c holesterol, apoB, LDL-apoB and cholesterol-rich Lp-B family, percent change s in the levels of these variables were greater in the aggressive- than in the moderate-treatment groups. These treatments had only marginal effects i n increasing the levels of high density lipoprotein cholesterol, apoA-I and Lp-A-I and Lp-A-I:A-II families. The long-term aggressive treatment exerte d no effect on the concentrations of triglycerides, apoC-III, apoC-III in V LDL + LDL and triglyceride-rich Lp-B, families. Neither treatment affected the levels of Lp(a). The potentially modifying influence of warfarin and ap oE phenotypes on lovastatin-induced changes in lipoprotein variables was fo und to be of little significance. It is likely that the beneficial effect o f lovastatin in reducing the progression of atherosclerosis in grafts is me diated through its specific lowering effect on cholesterol-rich Lp-B partic les, (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.