Systematic review: the comparative effectiveness of percutaneous coronary interventions and coronary artery bypass graft surgery

Abstract

Background: The comparative effectiveness of coronary artery bypass graft (CABG) surgery and percutaneous coronary intervention (PCI) for patients in whom both procedures are feasible remains poorly understood.

Purpose: To compare the effectiveness of PCI and CABG in patients for whom coronary revascularization is clinically indicated.

Data sources: MEDLINE, EMBASE, and Cochrane databases (1966-2006); conference proceedings; and bibliographies of retrieved articles.

Study selection: Randomized, controlled trials (RCTs) reported in any language that compared clinical outcomes of PCI with those of CABG, and selected observational studies.

Data extraction: Information was extracted on study design, sample characteristics, interventions, and clinical outcomes.

Data synthesis: The authors identified 23 RCTs in which 5019 patients were randomly assigned to PCI and 4944 patients were randomly assigned to CABG. The difference in survival after PCI or CABG was less than 1% over 10 years of follow-up. Survival did not differ between PCI and CABG for patients with diabetes in the 6 trials that reported on this subgroup. Procedure-related strokes were more common after CABG than after PCI (1.2% vs. 0.6%; risk difference, 0.6%; P = 0.002). Angina relief was greater after CABG than after PCI, with risk differences ranging from 5% to 8% at 1 to 5 years (P < 0.001). The absolute rates of angina relief at 5 years were 79% after PCI and 84% after CABG. Repeated revascularization was more common after PCI than after CABG (risk difference, 24% at 1 year and 33% at 5 years; P < 0.001); the absolute rates at 5 years were 46.1% after balloon angioplasty, 40.1% after PCI with stents, and 9.8% after CABG. In the observational studies, the CABG-PCI hazard ratio for death favored PCI among patients with the least severe disease and CABG among those with the most severe disease.

Limitations: The RCTs were conducted in leading centers in selected patients. The authors could not assess whether comparative outcomes vary according to clinical factors, such as extent of coronary disease, ejection fraction, or previous procedures. Only 1 small trial used drug-eluting stents.

Conclusion: Compared with PCI, CABG was more effective in relieving angina and led to fewer repeated revascularizations but had a higher risk for procedural stroke. Survival to 10 years was similar for both procedures.