Peripheral arterial disease: Longer duration of dual antiplatelet therapy after stent placement improves outcomes

In a study published online by JAMA Cardiology, Marco Valgimigli, M.D., Ph.D., of Bern University Hospital, Bern, Switzerland, and colleagues assessed the efficacy and safety of prolonged (24 months) vs short (6 months or less) dual antiplatelet therapy in patients with peripheral arterial disease undergoing percutaneous coronary intervention. The study is being released to coincide with its presentation at the European Society of Cardiology Congress 2016.

Concomitant (accompanying) peripheral arterial disease (PAD) is increasingly recognized as an important risk factor among patients with coronary artery disease. Evidence suggests that extended duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI; a procedure used to open narrowed coronary arteries, such as stent placement) provides more effective protection against atherothrombotic events (formation of a blood clot) compared with short-term regimens, at the risk of more frequent bleeding.

This study, which assessed patients from tertiary care hospitals with stable coronary artery disease or acute coronary syndromes with or without concomitant PAD, was a subanalysis of the PRODIGY trial, which compared the safety and efficacy profile of prolonged vs short duration of DAPT in a population of patients undergoing coronary stenting.

The analysis included 246 and 1,724 patients with and without PAD, respectively. The authors write that the primary findings were that in patients undergoing PCI, concomitant PAD was associated with a 2-fold increased risk of ischemic events, whereas the risk of bleeding was unaffected; and prolonged DAPT duration of 24 months after PCI reduced the risk of death, heart attack, or cerebrovascular accident (stroke) compared with short DAPT of 6 months or less in patients with PAD. The improved efficacy of prolonged DAPT in patients with PAD was not offset by an increased risk of actionable (requiring clinical action) bleeding episodes. The researchers note that this finding requires further evaluation in adequately powered studies.