Extended treatment with dual antiplatelet therapy reduced the risk of ischemic events and bleeding after PCI in patients with and without peripheral arterial disease, according to findings presented at the American Heart Association Scientific Sessions.
“PAD in patients requiring PCI results in a high risk of adverse events,” Eric A. Secemsky, MD, MSc, of Massachusetts General Hospital, said during his presentation. “We conducted this analysis to determine whether patients with PAD in the DAPT study experienced different ischemic event reductions and bleeding risks with extended duration of DAPT.”
The DAPT study, which was presented at the AHA Scientific Sessions in 2014, demonstrated that patients treated with DAPT for 30 months after drug-eluting stent implantation had a reduced risk of stent thrombosis and major adverse cardiac and cerebrovascular events compared with patients treated with DAPT for 12 months, although the risk of bleeding increased. The study included 25,682 patients who underwent PCI with coronary stenting. Following 12 months of thienopyridine plus aspirin, 11,648 patients were randomized to thienopyridine plus aspirin vs. placebo plus aspirin for 18 months. Study endpoints included ischemic events (myocardial infarction or definite/probable stent thrombosis) and bleeding (GUSTO moderate or severe).
Among all enrolled patients, 1,745 (6.8%) had PAD. These patients were older and presented with more cardiac risk factors, including diabetes, hypertension and prior MI, although they were less likely to present with MI at the time of the index PCI, according to the study results. In addition, “patients with PAD more often presented with stable angina, more often had disease involving the left main coronary artery, or the venous graft, and more often had lesions, including in-stent restenosis, and heavily calcified lesions,” Secemsky said.
Patients with PAD experienced greater rates of ischemic events (6.2% vs. 2.7%; P < .01) and bleeding (5.7% vs. 2.5%; P < .01) in the first 12 months, according to the findings from Secemsky and colleagues. Among patients randomized to treatment with either thienopyridine plus aspirin or placebo plus aspirin, 649 (5.6%) had PAD. Between 12 and 30 months, randomized patients with PAD experienced higher rates of ischemic events (6.0% vs. 2.9%; P < .01) and bleeding (4.9% vs. 1.7%; P < .01) compared to patients without PAD. For individuals with and without PAD, continued treatment with thienopyridine was associated with consistent decreases in ischemic events (PAD: 4.7% vs. 7.3%; HR, 0.63; 95% CI, 0.32-1.22; no PAD: 2.0% vs. 3.8%; HR, 0.53; 95% CI, 0.42-0.66; interaction: P = .70), but increased rates of bleeding (PAD: 6.3% vs. 3.5%; HR, 1.82; 95% CI, 0.87-3.83; no PAD: 2.2% vs. 1.3%; HR, 1.66; 95% CI, 1.23–2.24; interaction: P = .28).
“PAD is associated with higher risks of bleeding and ischemic events after coronary stenting, both at 12 months and 12 to 30 months,” Secemsky said. “We saw an overall similar magnitude of risk reduction with thienopyridine treatment. Patients with PAD experienced consistent ischemic benefits and bleeding risks with 30 months of DAPT compared to those without PAD.” – by Julia Ernst, MS
Secemsky E, et al. Abstract 168. Presented at: American Heart Association Scientific Sessions; Nov. 12-16, 2016; New Orleans.
Disclosures: Secemsky reports no relevant financial disclosures. Please see the full study for a list of all other authors’ relevant financial disclosures.