The benefit was mainly attributable to a reduction in repeat revascularization procedures in the first year, the researchers say.
The study also found that treatment with the glycoprotein IIb/IIIa inhibitor abciximab reduced early stent thrombosis, but at the expense of more bleeding complications.
“This study does not support routine use of abciximab in addition to aspirin, clopidogrel, and heparin; although acute stent thrombosis in the first 30 days was reduced, this was accompanied by more bleeding complications, and overall outcome at one year was not influenced,” the researchers conclude.
The DEBATER study results are available online now in JACC: Cardiovascular Interventions.
By way of background, the authors note that U.S. and European guidelines recommend primary PCI with stenting in the setting of STEMI, based on studies that have demonstrated the usefulness of BMS in this setting. Although drug-eluting stents have been used widely in unstable angina and in acute MI, their routine use in STEMI remains “a point of debate,” they note. Likewise, the benefits of abciximab in STEMI remain unclear, particularly when clopidogrel is used.
Dr. Nico H. Pijls from Catharina Hospital Eindhoven, the Netherlands, and colleagues designed the DEBATER trial to investigate the superiority of SES over BMS in unselected patients with STEMI undergoing primary PCI and the superiority of abciximab over no abciximab in the clopidogrel era.
A total of 907 patients referred to Catharina Hospital were randomized to SES or BMS, and to abciximab or no abciximab in a prospective, randomized, open 2 X 2 factorial trial.
All patients received aspirin (300 mg chewed or 500 mg IV), clopidogrel (600 mg) and a fixed bolus of IV unfractionated heparin (5,000 IU) in the ambulance. Before angiography, all patients received an additional IV bolus of heparin (5,000 IU). After primary PCI, aspirin 80 mg per day was given indefinitely, and clopidogrel was prescribed (75 mg/day) for at least one month after BMS and 6 to 12 months after SES. Patients allocated to abciximab received a 0.25 mg/kg bolus after stent placement followed by an infusion of 0.125 mcg/kg/min for 12 hours.
The investigators report that, at one year, the rate of major adverse cardiac and cardiovascular events (the primary outcome) was lower in the SES arm (16.5% vs 25.8%; p=0.001), mainly driven by fewer repeat revascularization procedures (9.8% vs 16.8%; p =0.003). The cumulative incidence of death and MI were not significantly different (5.2% vs 5.8%; p=0.68).
At 30 days, the rate of the composite of death, target vessel MI, target vessel revascularization, and bleeding was lower in the abciximab arm (8.2% vs 12.4%; p=0.04), driven mainly by less target vessel revascularization due to less stent thrombosis (1.2% vs 7.4%; p<0.001). However, bleeding complications occurred significantly more often in the abciximab arm (5.7% vs 2.8%; p=0.03).
The researchers say the broad inclusion criteria, reflecting patients seen in everyday practice is a strength of the study. Another strength is randomizing patients before angiography was performed.
They note that the DEBATER study was conducted at a single high-volume center performing roughly 1500 primary PCIs annually. “Our results may not apply to low-volume centers and regions lacking a well-organized referral system,” they say.