Anticoagulation Duration for DES Implantation Evaluated in ISAR-TRIPLE Study

September 15, 2014—The ISAR-TRIPLE study investigating different durations of triple therapy for anticoagulation after drug-eluting stent (DES) implantation demonstrated that 6 weeks of drug therapy was not superior to 6 months of therapy with regard to net clinical outcomes. The ISAR-TRIPLE findings were presented at the 26th annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium in Washington, DC.

The background of the study is that a sizeable number of patients taking oral anticoagulation (OAC) undergo coronary stenting and require dual-antiplatelet therapy (DAPT) in addition to OAC. Such triple therapy confers an elevated bleeding risk. Shortening the duration of DAPT may reduce the excess bleeding risk; however, it may also have a negative impact on the risk of thrombotic complications.

According to the TCT press release, ISAR-TRIPLE is the first trial to examine the restriction of DAPT after DES implantation in the setting of concomitant aspirin and OAC with Vitamin K antagonists. The prospective, open-label trial randomized 614 patients in a 1:1 fashion to either 6 weeks or 6 months of clopidogrel therapy, in addition to aspirin plus an oral anticoagulant. The primary endpoint was a composite of death, myocardial infarction, definite stent thrombosis, stroke, or TIMI major bleeding at 9 months. The secondary endpoints included the composite ischemic endpoint as well as bleeding complications.

After 9 months, the primary endpoint occurred in 9.8% of patients in the 6-week group and 8.8% of patients in the 6-month group (P = .63). The composite of cardiac death, myocardial infarction, stent thrombosis, or ischemic stroke occurred at a similar rate in both the 6-week and 6-month groups (4% vs 4.3%, respectively; P = .87). A total of 5.3% of patients in the 6-week group experienced major bleeding, compared to 4% in the 6-month group (P = .44).

“The shortening of triple therapy neither reduced the incidence of TIMI major bleeding nor increased the incidence of the composite of ischemic events,” commented lead investigator Nikolaus Sarafoff, MD, in the TCT press release. “These results suggest that physician should weigh the trade-off between ischemic and bleeding risk when choosing the shorter or longer duration of triple therapy.” Dr. Sarafoff is from Deutsches Herzzentrum, Munich and Klinikum der Universität Munich in Germany.