SYNTAX: Major adverse cardiac, cerebrovascular event rate higher with PCI vs. CABG in diabetes

Patients with diabetes and left main or three-vessel disease who were treated with paclitaxel-eluting stents had an increased risk for major adverse cardiac and cerebrovascular events compared with patients treated with coronary artery bypass graft surgery, according to one-year results of the diabetes subgroup analysis of the SYNTAX trial.

SYNTAX researchers randomly assigned patients with (n=452) and without (n=1,348) diabetes who had main or three-vessel disease to receive paclitaxel-eluting stents (Taxus, Boston Scientific) or CABG. Most (94%) of the patients with diabetes had type 2 diabetes; 40.3% were insulin users and 59.7% were oral therapy users.

Subgroup

At one year, patients with diabetes assigned to paclitaxel-eluting stents had a higher rate for major adverse cardiac and cerebrovascular events compared with patients assigned CABG. Revascularization did not impact the rate for mortality/stroke/MI for patients with (10.3% CABG vs. 10.1% PES; P=.96) or without diabetes (6.8% CABG vs. 6.8% PES; P=.97). However, diabetes significantly increased the risk for mortality following both treatments.

Patients with diabetes had significantly increased morbidity after both paclitaxel-eluting stents and CABG. Patients without diabetes assigned to CABG had a 3.7-fold higher risk for stroke compared with those assigned to paclitaxel-eluting stents (2.2% vs. 0.5%, P=.006). Further, the risk for mortality was higher following paclitaxel-eluting stents for patients with diabetes and highly complex lesions compared with CABG (4.1% vs. 13.5%; P=.04).

Researchers reported a higher rate for repeat revascularization with paclitaxel-eluting stents for patients both with (6.4% vs. 20.3%; P=.001) and without diabetes (5.7% vs. 11.1%; P=.001).

According to the researchers, the higher one-year major adverse cardiac and cerebrovascular event rate among patients with diabetes and left main or three-vessel disease treated with paclitaxel-eluting stents may be driven by an increase in repeat revascularization.

Although further research is needed, “these results may extend the evidence base for drug-eluting stents (particularly PES) in select diabetic and non-diabetic patients with left main or three-vessel disease,” they wrote.

“On the basis of the SYNTAX trial findings, have drug-eluting stents removed the ‘death penalty’ associated with diabetes and multivessel percutaneous coronary intervention?” Harold L. Dauerman, MD, of the division of Cardiology at the University of Vermont College of Medicine, wrote in an accompanying editorial.

Dauerman said these findings present percutaneous coronary intervention as a “viable general option.” However, there are several caveats such as: multivessel PCI for patients with diabetes performed without DES may be associated with increased mortality; patients with diabetes who undergo PCI with DES are at higher risk for repeat revascularization with PCI vs. CABG; and clinical action is needed before the five-year follow-up data are released.

“Reversal of the BARI trial mortality signal moves the diabetic revascularization choice away from the black-or-white, life-or-death decision the BARI trial once described; instead, we can move diabetes, CABG and PCI back into the typical gray areas of clinical decision making that characterize routine practice,” Dauerman wrote. – by Jennifer Southall

Banning AP. J Am Coll Cardiol 2010;doi:10.1016/j.jacc.2009.09.057.

Dauerman HL. J Am Coll Cardiol. 2010;doi:10.1016/j.jacc.2009.09.056.