Antiplatelet Therapy Duration Following Bare Metal or Drug-Eluting Coronary Stents

Abstract

Importance Despite antirestenotic efficacy of coronary drug-eluting stents (DES) compared with bare metal stents (BMS), the relative risk of stent thrombosis and adverse cardiovascular events is unclear. Although dual antiplatelet therapy (DAPT) beyond one year provides ischemic event protection following DES, ischemic event risk is perceived to be less following BMS and the appropriate duration of DAPT following BMS is unknown. Objective To compare: (1) rates of stent thrombosis and major adverse cardiac and cerebrovascular events (MACCE; composite of death, myocardial infarction, or stroke) after 30 vs. 12 months of thienopyridine in patients treated with BMS taking aspirin; and (2) treatment duration effect within the combined cohorts of randomized DES or BMS-treated patients as prespecified, secondary analyses of the Dual Antiplatelet Therapy Study. Design, Setting, Participants International, multicenter, randomized, double-blinded, placebo-controlled trial, comparing extended (30 months) thienopyridine versus placebo in aspirin-treated patients who completed 12 months of DAPT without bleeding or ischemic events post-stenting. Study initiation August 2009 with last follow-up visit May 2014. Exposure/Intervention Continued thienopyridine or placebo at months 12-30 after stenting, in 11648 randomized patients treated with aspirin, of whom 1687 received BMS and 9961 DES. Main Outcome and Measures Stent thrombosis, MACCE, moderate/severe bleeding. Results Among 1687 BMS-treated patients randomized to continued thienopyridine vs. placebo, rates of stent thrombosis were 0.5% vs. 1.11%, (N=4 vs. 9, hazard ratio 0.49, 95% CI 0.15-1.64, P=0.24), MACCE 4.04% vs. 4.69%, (N=33 vs. 38, hazard ratio 0.92, 95% CI 0.57-1.47, P=0.72) and moderate/severe bleeding 2.03% vs. 0.90% (N=16 vs. 7, P=0.07), respectively. Among all 11,648 randomized patients (both BMS- and DES-treated), stent thrombosis rates were 0.41% vs. 1.32%, (N=23 vs. 74, hazard ratio 0.31, 95% CI 0.19-0.50, P<0.001), MACCE 4.29% vs. 5.74% (N=244 vs. 323, hazard ratio 0.73, 95% CI 0.62-0.87, P<0.001), and moderate/severe bleeding 2.45% vs. 1.47% (N=135 vs. 80, P<0.001). Conclusions and Relevance Among patients undergoing coronary stenting with BMS and who tolerated 12 months of thienopyridine, continuing thienopyridine for an additional 18 months compared with placebo did not result in statistically significant differences in rates of stent thrombosis, MACCE, or moderate/severe bleeding. However, the BMS subset may have been underpowered to identify such differences and further trials are suggested. (DAPT ClinicalTrials.gov number NCT00977938).

Diabetes Mellitus and Prevention of Late Myocardial Infarction After Coronary Stenting in the Randomized Dual Antiplatelet Therapy Study

“…The DAPT Study, the design of which has been previously described, 18 compared 30 versus 12 months of thienopyridine therapy (clopidogrel or prasugrel) when prescribed in addition to aspirin following coronary stenting with either DES 17 or bare metal stents 19 for the prevention of stent thrombosis or major adverse cardiovascular and cerebrovascular events, a composite of all-cause mortality, MI, or stroke (MACCE; ClinicalTrials.gov NCT00977938). Each participating institution's ethics committee approved the study, and each patient gave written informed consent.…”

Duration of Dual Antiplatelet Therapy: A Systematic Review for the 2016 ACC/AHA Guideline Focused Update on Duration of Dual Antiplatelet Therapy in Patients With Coronary Artery Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

“…), using datasets whenever possible that excluded patients receiving BMS. Of note, several RCTs contained summary statistics for patients treated with BMS or DES, but 2 RCTs presented separate summaries for patients receiving DES only, 14,15,23,29 and these were used in the present analysis.…”

Endoscopy in patients on antiplatelet or anticoagulant therapy, including direct oral anticoagulants: British Society of Gastroenterology (BSG) and European Society of Gastrointestinal Endoscopy (ESGE) guidelines

“…If, after discussion with a cardiologist, DAPT needs to be modified for a non-cardiac procedure during the 12 months following coronary stent insertion, then only the P2Y12 inhibitor should be discontinued (for 5 days prior to the procedure)-the aspirin should be continued; 6. The situation is further complicated by recent data (DAPT trial) 51 which suggests that certain patients may benefit from an extension of their DAPT till at least 30 months. This study reported fewer ischaemic events in patients receiving DAPT up till 30 months than those discontinuing at 12 months, but at the cost of a higher risk of (non-fatal) bleeding; 7.…”