One-Year CARDia Results Look at PCI in Diabetic Patients

November 25, 2009—In an expedited publication online ahead of print in the Journal of the American College of Cardiology, Akhil Kapur, MBChB, MD, et al published 1-year results from the United Kingdom–based CARDia (Coronary Artery Revascularization in Diabetes) trial.

According to the investigators, CARDia is the first randomized trial of coronary revascularization in diabetic patients. The investigators reported that the 1-year results did not show that percutaneous coronary intervention (PCI) is noninferior to coronary artery bypass grafting (CABG). However, the CARDia trial did show that multivessel PCI is feasible in patients with diabetes. Longer-term follow-up and data from other trials will be needed to provide a more precise comparison of the efficacy of these two revascularization strategies, the investigators concluded.

The purpose of this study was to compare the safety and efficacy of PCI with stenting against CABG in patients with diabetes and symptomatic multivessel coronary artery disease. The background of the study is that CABG is the established method of revascularization in patients with diabetes and multivessel coronary disease, but with advances in PCI, there is uncertainty as to whether CABG remains the preferred method of revascularization.

As detailed by the investigators, the primary outcome was a composite of all-cause mortality, myocardial infarction (MI), and stroke, and the main secondary outcome included the addition of repeat revascularization to the primary outcome events. A total of 510 diabetic patients with multivessel or complex single-vessel coronary disease from 24 centers were randomized to PCI plus stenting (and routine abciximab) or CABG. The primary comparison used a noninferiority method with the upper boundary of the 95% confidence interval (CI) not to exceed 1.3 to declare PCI noninferior. Bare-metal stents were used initially, but a switch to Cypher sirolimus-eluting stents (Cordis Corporation, Bridgewater, NJ) was made when these became available.

At 1-year of follow-up, the composite rate of death, MI, and stroke was 10.5% in the CABG group and 13% in the PCI group (hazard ratio [HR], 1.25; 95% CI, 0.75–2.09; P = 0.39), all-cause mortality rates were 3.2% in both groups, and the rates of death, MI, stroke, or repeat revascularization were 11.3% and 19.3% (HR, 1.77; 95% CI, 1.11–2.82; P = .02), respectively. When the patients who underwent CABG were compared with the subset of patients who received drug-eluting stents (69% of patients), the primary outcome rates were 12.4% and 11.6% (HR, 0.93; 95% CI, 0.51–1.71; P = 0.82), respectively.