Organ-specific bleeding patterns of anticoagulant therapy: lessons from clinical trials

Thomas Vanassche; Jack Hirsh; John W. Eikelboom; Jeffrey S. Ginsberg

doi:10.1160/th14-04-0346

Thrombosis and Haemostasis, Table of Contents

Thromb Haemost 2014; 112(05): 918-923
DOI: 10.1160/th14-04-0346

Theme Issue Article

Schattauer GmbH

Organ-specific bleeding patterns of anticoagulant therapy: lessons from clinical trials

Authors

Thomas Vanassche

¹Population Health Research Institute, Thrombosis and Atherosclerosis Research Institute, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada
Jack Hirsh

¹Population Health Research Institute, Thrombosis and Atherosclerosis Research Institute, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada
John W. Eikelboom

¹Population Health Research Institute, Thrombosis and Atherosclerosis Research Institute, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada
Jeffrey S. Ginsberg

¹Population Health Research Institute, Thrombosis and Atherosclerosis Research Institute, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada

Abstract

Summary

Anticoagulants are effective at preventing and treating thrombosis, but can cause bleeding. For decades, vitamin K antagonists (VKAs) have been the only available oral anticoagulants. The development of non-VKA oral anticoagulants (NOACs), which inhibit either factor Xa or thrombin stoichiometrically, has provided alternatives to VKAs for several indications. The results of recent large-scale randomised controlled trials comparing NOACs with VKAs for the prevention of stroke in patients with non-valvular atrial fibrillation (AF) have produced some unexpected results. As a group, NOACs showed similar efficacy as warfarin, but a reduced risk of major bleeding. The reduction in bleeding with NOACs was greatest with intracranial hemorrhage. In contrast, the relative risk of gastro-intestinal bleeding was increased with some NOACs. In this review, we explore the potential mechanisms as well as the implications of these organ-specific bleeding patterns.

Keywords

Venous thrombosis - stroke prevention - thrombosis

Full Text

References

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