Ten-Year Follow-Up Survival of the Medicine, Angioplasty, or Surgery Study (MASS II)

Background— This study compared the 10-year follow-up of percutaneous coronary intervention (PCI), coronary artery surgery (CABG), and medical treatment (MT) in patients with multivessel coronary artery disease, stable angina, and preserved ventricular function. Methods and Results— The primary end points were overall mortality, Q-wave myocardial infarction, or refractory angina that required revascularization. All data were analyzed according to the intention-to-treat principle. At a single institution, 611 patients were randomly assigned to CABG (n=203), PCI (n=205), or MT (n=203). The 10-year survival rates were 74.9% with CABG, 75.1% with PCI, and 69% with MT ( P =0.089). The 10-year rates of myocardial infarction were 10.3% with CABG, 13.3% with PCI, and 20.7% with MT ( P <0.010). The 10-year rates of additional revascularizations were 7.4% with CABG, 41.9% with PCI, and 39.4% with MT ( P <0.001). Relative to the composite end point, Cox regression analysis showed a higher incidence of primary events in MT than in CABG (hazard ratio 2.35, 95% confidence interval 1.78 to 3.11) and in PCI than in CABG (hazard ratio 1.85, 95% confidence interval 1.39 to 2.47). Furthermore, 10-year rates of freedom from angina were 64% with CABG, 59% with PCI, and 43% with MT ( P <0.001). Conclusions— Compared with CABG, MT was associated with a significantly higher incidence of subsequent myocardial infarction, a higher rate of additional revascularization, a higher incidence of cardiac death, and consequently a 2.29-fold increased risk of combined events. PCI was associated with an increased need for further revascularization, a higher incidence of myocardial infarction, and a 1.46-fold increased risk of combined events compared with CABG. Additionally, CABG was better than MT at eliminating anginal symptoms. Clinical Trial Registration Information— URL: http://www.controlled-trials.com. Registration number: ISRCTN66068876.