Dabigatran versus vitamin k antagonist: an observational across-cohort comparison in acute coronary syndrome patients with atrial fibrillation

J Thromb Haemost. 2018 Mar;16(3):465-473. doi: 10.1111/jth.13931. Epub 2018 Jan 19.

Abstract

Essentials Acute coronary syndrome (ACS) with atrial fibrillation (AF) is a therapeutic challenge. Dual and triple antithrombotic therapy showed a similar thrombotic risk in ACS patients with AF. The omission of aspirin during the first month did not increase the rate of ischemic events. Replacement of vitamin K antagonist by dabigatran leads to an increased thrombotic risk.

Summary: Background Dual antithrombotic therapy comprising a vitamin K antagonist (VKA) plus clopidogrel reduces the incidence of major bleeding compared with triple therapy (VKA + clopidogrel + aspirin) in acute coronary syndrome (ACS) patients with atrial fibrillation (AF), with a similar thrombotic risk. The oral thrombin inhibitor dabigatran (150 mg twice a day) showed superiority over VKA in non-valvular AF, but data supporting its use in AF patients presenting with ACS are limited. Objective We sought to evaluate the efficacy of dabigatran vs. VKA in the management of AF patients undergoing percutaneous coronary intervention for an ACS. Methods In this open-label study, 133 consecutive patients received dabigatran plus clopidogrel. Another cohort of 133 patients treated with VKA plus clopidogrel was used as the control group. Results After propensity score adjustment, the cumulative incidence of major adverse cardiovascular events over 24 months was higher with dabigatran vs. VKA (adjusted hazard ratio, 2.28; 95% confidence interval, 1.46-3.56). Similar rates of major bleeding were found (adjusted hazard ratio, 1.17; 95% confidence interval, 0.46-2.96). Conclusions In AF patients presenting with ACS, replacement of VKA by dabigatran concurrently with clopidogrel is associated with an increased thrombotic risk, without a reduction in major bleeding.

Keywords: acute coronary syndrome; atrial fibrillation; oral thrombin inhibitor; vitamin K antagonist.

Publication types

  • Comparative Study
  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Coronary Syndrome / complications
  • Acute Coronary Syndrome / drug therapy*
  • Administration, Oral
  • Aged
  • Aged, 80 and over
  • Anticoagulants / administration & dosage
  • Aspirin / administration & dosage
  • Atrial Fibrillation / complications
  • Atrial Fibrillation / drug therapy*
  • Blood Platelets / cytology
  • Clopidogrel / administration & dosage
  • Cohort Studies
  • Coronary Angiography
  • Dabigatran / administration & dosage*
  • Female
  • Glomerular Filtration Rate
  • Hemorrhage / prevention & control
  • Humans
  • Incidence
  • Ischemia
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Outcome Assessment, Health Care
  • Patient Safety
  • Phenindione / administration & dosage
  • Phenindione / analogs & derivatives
  • Propensity Score
  • Proportional Hazards Models
  • Risk
  • Treatment Outcome
  • Vitamin K / antagonists & inhibitors*

Substances

  • Anticoagulants
  • Vitamin K
  • Phenindione
  • Clopidogrel
  • fluindione
  • Dabigatran
  • Aspirin