Abstract 16929: Propensity-matched Analysis of Triple Oral Antithrombotic Therapy versus Dual Antiplatelet Therapy Following Percutaneous Coronary Intervention
Introduction: Triple oral antithrombotic therapy (TOAT) (aspirin, clopidogrel, and warfarin) is associated with an increased risk of bleeding. Despite this, the optimal management of patients with indications for warfarin following percutaneous coronary intervention (PCI) has not been established. We sought to compare long-term clinical outcomes between patients receiving TOAT with those receiving dual antiplatelet therapy (DAPT) (aspirin and clopidogrel) after PCI.
Hypothesis: Patients with clinical indications for warfarin have higher baseline risk which is largely responsible for the observed differences in outcomes between patients receiving TOAT vs. DAPT.
Methods: Retrospective analysis of prospectively collected data from 9,009 patients. The primary outcome was a composite of all-cause mortality, ischemic or embolic events (myocardial infarction or stroke), or bleeding. Secondary outcomes were death plus ischemic or embolic events, death plus bleeding, death, MI, stroke, and bleeding. A 2:1 propensity matched analysis was also performed.
Results: In 9,009 patients, 812 received TOAT and 8,197 received DAPT. Median follow-up was 61 months. The primary end point occurred in 2,749 patients. At 1 year, 22% of patients treated with TOAT had the primary endpoint versus 11% of DAPT patients (p<0.001). At 1 year, secondary end points of death or ischemic or embolic events (19% vs. 10%, p<0.001), and death or bleeding events (15% vs. 5%, p<0.001) also occurred with a higher frequency with TOAT. After propensity matched analysis the above differences were no longer significant with 1 year primary endpoint rates of 19% vs. 17% respectively (HR 1.95%, CI 0.88, 1.47; p = 0.33). Following propensity matching the only significant difference between TOAT and DAPT groups was minor bleeding (5% vs. 2%; HR 2.65, 95% CI 1.39, 5.03; p=0.003).
Conclusions: In a large single center registry with comprehensive follow up, patients treated with TOAT had higher rates of ischemic and bleeding events. However, when baseline risks are accounted for event rates are similar, other than minor bleeding, indicating patient risk characteristics are largely responsible for the observed differences in outcomes.
Author Disclosures: D.B. Spoon: None. R.J. Lennon: None. J.P. Slusser: None. D.R. Holmes: None. K.R. Bailey: None. V. Mathew: None. R.D. McBane: None. R. Gulati: None. G.S. Sandhu: None. C.S. Rihal: None.
- © 2015 by American Heart Association, Inc.