Outcomes with coronary artery bypass graft surgery versus percutaneous coronary intervention for patients with diabetes mellitus: can newer generation drug-eluting stents bridge the gap?

BACKGROUND: Coronary artery bypass graft surgery (CABG) compared with percutaneous coronary intervention (PCI) reduces mortality in patients with diabetes mellitus. However, prior trials compared CABG with balloon angioplasty or older generation stents, and it is not known if the gap between CABG and PCI can be reduced by newer generation drug-eluting stents.

METHODS AND RESULTS: PUBMED/EMBASE/CENTRAL search for randomized trials comparing mode of revascularization in patients with diabetes mellitus. Primary outcome was all-cause mortality. Secondary outcomes were myocardial infarction, repeat revascularization, and stroke. Mixed treatment comparison analyses were performed using a random-effects Poisson regression model. Sixty-eight randomized trials that enrolled 24 015 diabetic patients with a total of 71 595 patient-years of follow-up satisfied our inclusion criteria. When compared with CABG (reference rate ratio [RR]=1.0), PCI with paclitaxel-eluting stent (RR=1.57 [1.15-2.19]) or sirolimus-eluting stent (RR=1.43 [1.06-1.97]) was associated with an increase in mortality. However, PCI with cobalt-chromium everolimus-eluting stent (RR=1.11 [0.67-1.84]) was not associated with a statistically significant increase in mortality. When compared with CABG, there was excess repeat revascularization with PCI, which progressively declined from plain old balloon angioplasty (341% increase) to bare metal stent (218% increase) to paclitaxel-eluting stent (81% increase) and to sirolimus-eluting stent (47% increase). However, for PCI with cobalt-chromium everolimus-eluting stent (RR=1.31 [0.74-2.29]), the excess repeat revascularization was not statistically significant although the point estimate favored CABG. CABG was associated with numerically higher stroke.

CONCLUSIONS: In patients with diabetes mellitus, evidence from indirect comparison shows similar mortality between CABG and PCI using cobalt-chromium everolimus-eluting stent. CABG was associated with numerically excess stroke and PCI with cobalt-chromium everolimus-eluting stent with numerically increased repeat revascularization. This hypothesis needs to be tested in future trials.