DAPT Study Subanalysis Focuses on EES Subgroup

Treating eligible patients with everolimus-eluting stents alongside long-term DAPT may be a viable strategy for secondary prevention of stent thrombosis, according to findings presented in a Featured Clinical Research session yesterday and simultaneously published online ahead of print in JACC: Cardiovascular Interventions.

Using data from the DAPT Study, James B. Hermiller Jr., MD, of St. Vincent Hospital/The Heart Center of Indiana in Indianapolis, and colleagues examined the interplay between stent type and DAPT duration. Out of 22,866 DES-treated patients in the trial, 4,703 received EES and were randomized at 12 months to aspirin plus either continued thienopyridine (n = 2,345) or placebo (n = 2,358). Baseline characteristics were well matched between groups and, at 30 months, follow-up data were available on approximately 95% of patients.

Within the EES subgroup, patients on extended DAPT had reduced risk for stent thrombosis and MI compared with those on aspirin/placebo but also were at an increased risk for bleeding. Their mortality risk also was elevated, particularly deaths from noncardiovascular causes (Figure).

“Cancer-related death – not related to bleeding – accounted for the majority of the mortality difference observed in the DAPT Study, possibly related to imbalance of patients with cancer at enrollment,” Hermiller said.

Importantly, there are several limitations to the current subanalysis, he cautioned. These include it being post hoc and not powered for treatment comparisons as well as the fact that the DAPT Study did not randomize according to DES type.

Clinical implications

In response to a question posed by session moderator Spencer B. King III, MD, of Emory University in Atlanta, Ga. on the take-home message of the subanalysis, Hermiller said these results suggest that longer-term DAPT may be more appropriate for EES-treated patients who are at high risk for thrombosis but at low risk for bleeding, such as those with ACS or diabetes.

“I do think a long [course of] DAPT becomes … a secondary preventive strategy more than a strategy to prevent stent thrombosis,” Hermiller said. “Stent thrombosis rates are so low, this is really more a medical therapy and secondary preventive therapy today.”

Disclosures:

• Hermiller reports receiving grant/research support and consultant/honoraria fees from Abbott Vascular, Boston Scientific Corporation, Edwards Lifesciences, Medtronic and St. Jude Medical.
• King reports no relevant disclosures.