Reinitiation of Anticoagulation After Temporary Withdrawal of Vitamin K Antagonist

Summary

It is not known how to best restart warfarin after temporary withdrawal. Participants will be randomized to two groups. Group 1 will restart warfarin at their usual maintenance dose, group 2 will restart warfarin at double their maintenance dose for two days followed by their usual maintenance dose. The main outcome parameter will be the number of patients who are back in therapeutic INR (international normalized ratio) range 4, and 9 days after restarting anticoagulation with warfarin. Thromboembolic and/or bleeding events will be recorded as additional parameters. These data will be collected by a standardized telephone interview at 1 month. In addition, the investigators will evaluate a possible prothrombotic state by measuring the potential of thrombin generation and D-dimers in the subset of patients visiting HHS-General Hospital for their INR tests.

Timeline

Start

2011-04

Primary completion

2013-12

Completion

2013-12

Publications

• Background Schulman S, El Bouazzaoui B, Eikelboom JW, Zondag M. Clinical factors influencing the sensitivity to warfarin when restarted after surgery. J Intern Med. 2008 Apr;263(4):412-9. doi: 10.1111/j.1365-2796.2007.01913.x. Epub 2008 Jan 16.
• Results Schulman S, Hwang HG, Eikelboom JW, Kearon C, Pai M, Delaney J. Loading dose vs. maintenance dose of warfarin for reinitiation after invasive procedures: a randomized trial. J Thromb Haemost. 2014 Aug;12(8):1254-9. doi: 10.1111/jth.12613. Epub 2014 Jun 25.

Drugs

Indications