The Bypass Angioplasty Revascularization in Type 1 and Type 2 Diabetes Study: 5-year follow-up of revascularization with percutaneous coronary intervention versus coronary artery bypass grafting in diabetic patients with multivessel disease

Abstract

Objectives: The aim of the Bypass Angioplasty Revascularization in Type 1 and Type 2 Diabetes study was to assess percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) as treatments for multivessel coronary artery disease in diabetic patients.

Background: CABG is generally regarded as the treatment of choice for multivessel coronary artery disease in diabetes. PCI is an alternative therapy. The Bypass Angioplasty Revascularization in Type 1 and 2 Diabetes study compared long-term outcomes of CABG with PCI in diabetic patients treated during the bare-metal stent era.

Methods: We collected data prospectively on consecutive diabetic patients undergoing index angiography in a single tertiary centre from January 1998 to December 2001. Multivessel coronary artery disease was defined as more than 50% luminal stenosis in two or more vessels. Exclusion criteria included left main stem disease and previous revascularization.

Results: Two hundred and thirty-five eligible patients underwent CABG and 237 PCI. Median follow-up was 5.4 years. There were 46 (19%) deaths in the CABG group and 43 (18%) deaths in the PCI group (P = 0.64). Cox regression analysis revealed baseline glomerular filtration rate (hazard ratio 0.979, P = 0.001), age (hazard ratio 1.034, P = 0.033), urgent procedure (hazard ratio 1.97, P = 0.008) and myocardial infarction within 4 weeks (hazard ratio 2.494, P = 0.041) to be important predictors of outcome. At 5 years, there was no mortality difference (hazard ratio 1.0) following adjustment for baseline characteristics, and the Kaplan-Meier survival curves were similar. A subanalysis of patients with three-vessel disease revealed similar outcomes with both PCI and CABG.

Conclusion: In the Bypass Angioplasty Revascularization in Type 1 and Type 2 Diabetes study, diabetic patients with multivessel coronary artery disease had similar long-term mortality whether treated with CABG or PCI, the revascularization determined by the physician's choice. This was despite the frequent use of a strategy of selective revascularization in the PCI arm. Randomized trials comparing PCI and CABG specifically in diabetes, that is, Coronary Artery Revascularization in Diabetes and Future Revascularization Evaluation in Diabetes Mellitus: Optimal Management, will show whether drug-eluting stents further enhance PCI outcomes over the long term.