Effect of complete revascularization on 10-year survival of patients with stable multivessel coronary artery disease: MASS II trial.

Background: The importance of complete revascularization remains unclear and contradictory. This current investigation compares the effect of complete revascularization on 10-year survival of patients with stable multivessel coronary artery disease (CAD) who were randomly assigned to percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG).

Methods And Results: This is a post hoc analysis of the Second Medicine, Angioplasty, or Surgery Study (MASS II), which is a randomized trial comparing treatments in patients with stable multivessel CAD, and preserved systolic ventricular function. We analyzed patients who underwent surgery (CABG) or stent angioplasty (PCI). The survival free of overall mortality of patients who underwent complete (CR) or incomplete revascularization (IR) was compared. Of the 408 patients randomly assigned to mechanical revascularization, 390 patients (95.6%) underwent the assigned treatment; complete revascularization was achieved in 224 patients (57.4%), 63.8% of those in the CABG group and 36.2% in the PCI group (P=0.001). The IR group had more prior myocardial infarction than the CR group (56.2% × 39.2%, P=0.01). During a 10-year follow-up, the survival free of cardiovascular mortality was significantly different among patients in the 2 groups (CR, 90.6% versus IR, 84.4%; P=0.04). This was mainly driven by an increased cardiovascular specific mortality in individuals with incomplete revascularization submitted to PCI (P=0.05).

Conclusions: Our study suggests that in 10-year follow-up, CR compared with IR was associated with reduced cardiovascular mortality, especially due to a higher increase in cardiovascular-specific mortality in individuals submitted to PCI.

Clinical Trial Registration Information: URL: http://www.controlled-trials.com.

Registration Number: ISRCTN66068876.