EFFECT OF SIMVASTATIN ON CORONARY ATHEROMA - THE MULTICENTER ANTI-ATHEROMA STUDY (MAAS)

It has yet to be established whether substantial reduction of plasma l ipids will lead to retardation, and to what extent and how quickly, of diffuse and focal coronary atheroma. The Multicentre Anti-Atheroma St udy (MAAS) is randomised double-blind clinical trial of 381 patients w ith coronary heart disease assigned to treatment with diet and either simvastatin 20 mg daily or placebo for 4 years. Patients on simvastati n had a 23% reduction in serum cholesterol, a 31% reduction in low-den sity lipoprotein cholesterol, and a 9% increase in high-density lipopr otein cholesterol compared with placebo over 4 years. Quantitative cor onary angiography was done at baseline, and after 2 and 4 years. 167 p atients (89%) on placebo and 178 (92%) on simvastatin had baseline and follow-up angiograms. In the placebo group there were reductions in m ean lumen diameter (-0.08 mm) and in minimum lumen diameter (-0.13 mm) . Treatment effects were + 0.06 (95% Cl 0.02 to 0.10) and + 0.08 mm (0 .03 to 0.14) for mean and minimum lumen diameter, respectively (combin ed p = 0.006). Patients on placebo had an increase in mean diameter st enosis of 3.6% and the treatment effect of simvastatin was - 2.6% (- 4 .4 to - 0.8). Treatment effects were observed regardless of diameter s tenosis at baseline. On a per-patient basis, angiographic progression occurred less often in the simvastatin group, 41 versus 54 patients; a nd regression was more frequent, 33 versus 20 patients (combined p = 0 .02). Significantly more new lesions and new tote I occlusions develop ed in the placebo group, 48 versus 28, and 18 versus 8, respectively. There was no difference in clinical outcome. The numbers of patients w ho died or had a myocardial infarction were 16 and 14 in the placebo a nd simvastatin groups, respectively. In the placebo group more patient s underwent coronary angioplasty or re-vascularisation, 34 versus 23 o n simvastatin. The trial showed that 20 mg simvastatin daily over 4 ye ars reduces hyperlipidaemia and slows progression of diffuse and focal coronary atherosclerosis.