Evaluation of Safety of Warfarin in Combination with Antiplatelet Therapy for Patients Treated with Coronary Stents for Acute Myocardial Infarction

Abstract

The safety and efficacy of treating recently stented patients on combination antiplatelet therapy with warfarin for clinical indications in unknown. Therefore, we examined the use of warfarin in a population of patients with myocardial infarction (MI) treated with coronary stenting. We performed a retrospective analysis comparing patients who underwent successful coronary stenting for acute MI and were discharged on either warfarin and combination platelet therapy for clinical indications or combination antiplatelet therapy alone. There was a nonsignificant trend toward reinfarction at 6 and 12 months in warfarin-treated patients. Warfarin-treated patients had significantly higher rates of transfusion compared to nonwarfarin-treated patients at 12 months (21% vs 0%, P=0.028). There were no significant predictors of reinfarction in 6 and 12 months in multivariate analysis. These data demonstrate that warfarin anticoagulation, in combination with successful coronary stenting for acute MI and antiplatelet therapy, does not reduce risk of reinfarction but is associated with increased rates of transfusion.

Incidence and Prevention of Ischemic Stroke following Myocardial Infarction: Review of Current Literature

“…AF, prosthetic heart valves, venous thromboembolism and LVMT) already on DT can be a problem, as the risk of bleeding from prolonged therapy with aspirin, clopidogrel and warfarin is poorly understood. Two retrospective studies [46, 47] have attempted to analyze the safety and efficacy of triple therapy and found higher rates of bleeding or need for transfusion. Another large population-based observational cohort study [48] from Canada studied 21,443 elderly survivors of acute MI over a 4-year period for any hospitalization for bleeding and found a trend toward increased bleeding with triple therapy.…”

Antithrombotic Regimens for Patients Taking Oral Anticoagulation After Coronary Intervention: A Meta‐analysis of 16 Clinical Trials and 9185 Patients

“…From 625 initial citations, 16 eligible studies including a total of 9185 patients were identified in the present meta‐analysis,4, 5, 6, 7, 12, 14, 15, 19, 20, 21, 22, 23, 24, 25, 26, 27 with 5680 patients in the triple therapy group and 3505 in the dual therapy group (Figure 1). …”

“…Finally, 12 studies were identified in the DAPT subgroup,4, 5, 6, 7, 19, 20, 21, 22, 23, 24, 25, 26 with the other 4 studies included in the OAC/C subgroup 12, 14, 15, 27…”

Minimizing the Risks of Anticoagulants and Platelet Inhibitors

“…Observational data demonstrate a higher rate of bleeding with triple therapy than with antiplatelet therapy alone. 38 Warfarin is still the most effective agent in many settings, so its use in combination with other antithrombotics is often unavoidable. 39 …”