Antiplatelet Therapy and Adverse Hematologic Events During Heart Mate II Support

Circ Heart Fail. 2016 Jan;9(1):e002296. doi: 10.1161/CIRCHEARTFAILURE.115.002296.

Abstract

Background: Hematologic adverse events are common during continuous flow left ventricular assist device support; yet, their relation to antiplatelet therapy, including aspirin (ASA) dosing, is uncertain.

Methods and results: A single-center retrospective review of all patients supported by a continuous flow left ventricular assist device (Heart Mate II) from June 2006 to November 2014 was conducted. Patients were categorized into 3 groups: (1) ASA 81 mg+dipyridamole 75 mg daily (n = 26) with a target international normalized ratio (INR) of 2 to 3 from June 2006 to August 2009; (2) ASA 81 mg daily (n = 18) from September 2009 to August 2011 with a target INR of 1.5 to 2; and (3) ASA 325 mg daily from September 2011 to November 2014 with a target INR of 2 to 3 (n = 70). Hemorrhagic and thrombotic outcomes were retrieved ≤ 365 days after implantation. Cumulative survival free from adverse events was calculated using Kaplan-Meier curves and Cox proportional hazard ratios were generated. Hemorrhagic events occurred in 6 patients on ASA 81 mg+dipyridamole (26%; 0.42 events per patient year; mean INR at event, 2.2), 4 patients on ASA 81 mg (22%; 0.38 events per patient year; mean INR at event, 2.0), and in 38 patients on ASA 325 mg (54%; 1.4 events per patient year; mean INR at event, 2.2); P = 0.004. Patients on ASA 325 mg had a higher adjusted hazard ratio of 2.9 (95% confidence interval, 1.2-7.0 versus ASA 81 mg+dipyridamole; P = 0.02) and 3.4 (95% confidence interval, 1.2-9.5 versus ASA 81 mg; P = 0.02) for hemorrhagic events. Thrombotic events rates were not different between groups.

Conclusions: High-dose ASA in Heart Mate II patients treated concomitantly with warfarin is associated with an increased hazard of bleeding but does not reduce thrombotic events.

Keywords: aspirin; hemorrhage; international normalized ratio; intracranial hemorrhage; thrombus.

Publication types

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

MeSH terms

  • Adult
  • Aged
  • Anticoagulants / adverse effects
  • Aspirin / adverse effects*
  • Chi-Square Distribution
  • Dipyridamole / adverse effects*
  • Disease-Free Survival
  • Drug Therapy, Combination
  • Female
  • Heart Failure / blood
  • Heart Failure / diagnosis
  • Heart Failure / physiopathology
  • Heart Failure / therapy*
  • Heart-Assist Devices / adverse effects*
  • Hemorrhage / chemically induced*
  • Hemorrhage / diagnosis
  • Hemorrhage / epidemiology
  • Humans
  • International Normalized Ratio
  • Kaplan-Meier Estimate
  • Linear Models
  • Male
  • Middle Aged
  • Multivariate Analysis
  • New York City / epidemiology
  • Platelet Aggregation Inhibitors / adverse effects*
  • Prevalence
  • Proportional Hazards Models
  • Prosthesis Design
  • Retrospective Studies
  • Risk Assessment
  • Risk Factors
  • Thrombosis / diagnosis
  • Thrombosis / epidemiology
  • Thrombosis / prevention & control*
  • Time Factors
  • Treatment Outcome
  • Ventricular Function, Left
  • Warfarin / adverse effects

Substances

  • Anticoagulants
  • Platelet Aggregation Inhibitors
  • Warfarin
  • Dipyridamole
  • Aspirin