Five-year follow-up of the Medicine, Angioplasty, or Surgery Study (MASS II): a randomized controlled clinical trial of 3 therapeutic strategies for multivessel coronary artery disease.
BACKGROUND
Despite routine use of coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI), no conclusive evidence exists that either modality is superior to medical therapy (MT) alone for treating multivessel coronary artery disease with stable angina and preserved ventricular function.


RESULTS
The primary end points were total mortality, Q-wave myocardial infarction, or refractory angina requiring revascularization. The study comprised 611 patients randomly assigned to undergo CABG (n=203), PCI (n=205), or MT (n=203). At the 5-year follow-up, the primary end points occurred in 21.2% of patients who underwent CABG compared with 32.7% treated with PCI and 36% receiving MT alone (P=0.0026). No statistical differences were observed in overall mortality among the 3 groups. In addition, 9.4% of MT and 11.2% of PCI patients underwent repeat revascularization procedures compared with 3.9% of CABG patients (P=0.021). Moreover, 15.3%, 11.2%, and 8.3% of patients experienced nonfatal myocardial infarction in the MT, PCI, and CABG groups, respectively (P<0.001). The pairwise treatment comparisons of the primary end points showed no difference between PCI and MT (relative risk, 0.93; 95% confidence interval, 0.67 to 1.30) and a significant protective effect of CABG compared with MT (relative risk, 0.53; 95% confidence interval, 0.36 to 0.77).


CONCLUSIONS
All 3 treatment regimens yielded comparable, relatively low rates of death. MT was associated with an incidence of long-term events and rate of additional revascularization similar to those for PCI. CABG was superior to MT in terms of the primary end points, reaching a significant 44% reduction in primary end points at the 5-year follow-up of patients with stable multivessel coronary artery disease.
Hueb
Whady
W
Heart Institute of the University of São Paulo, São Paulo, Brazil. whady.hueb@incor.usp.br
Lopes
Neuza Helena
NH
Gersh
Bernard J
BJ
Soares
Paulo
P
Machado
Luiz A C
LA
Jatene
Fabio B
FB
Oliveira
Sergio A
SA
Ramires
Jose A F
JA
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000368:Aged; D000787:Angina Pectoris / Q000188:drug therapy / Q000601:surgery / Q000628:therapy; D015906:Angioplasty, Balloon, Coronary / Q000706:statistics & numerical data; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D002317:Cardiovascular Agents / Q000627:therapeutic use*; D001026:Coronary Artery Bypass / Q000706:statistics & numerical data; D003327:Coronary Disease / Q000178:diet therapy / Q000188:drug therapy / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D023903:Coronary Restenosis / Q000453:epidemiology / Q000601:surgery / Q000628:therapy; D018752:Diet, Fat-Restricted; D018572:Disease-Free Survival; D004359:Drug Therapy, Combination; D004562:Electrocardiography; D023381:Endpoint Determination; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D009566:Nitrates / Q000627:therapeutic use; D011379:Prognosis; D012086:Reoperation; D015607:Stents; D016019:Survival Analysis; D016896:Treatment Outcome
D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D002121:Calcium Channel Blockers; D002317:Cardiovascular Agents; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D009566:Nitrates