Reduced-dose warfarin or interrupted warfarin with heparin bridging for pacemaker or defibrillator implantation: A randomized trial.
Thromb Res. 2014 Aug 1;
Authors: Schulman S, Healey JS, Douketis JD, Delaney J, Morillo CA
BACKGROUND: Perioperative management with reduced-dose warfarin is of potential interest by eliminating the need for bridging while still maintaining a degree of anticoagulation. The outcomes of this regimen have not been well determined.
METHODS: In a randomized controlled trial we compared two regimens for management of anticoagulation with warfarin in patients with implantation of a pacemaker or defibrillator. Half dose of warfarin for 3-6days, depending on the baseline international normalized ratio (INR), before surgery aiming at an INR of ≤1.7 was compared with interrupted warfarin for 5days with preoperative bridging with low-molecular-weight heparin (LMWH) at therapeutic dose for 2.5days. Main safety outcome was pocket hematoma. Secondary outcomes were major bleeding, thromboembolism - all within 1month, days of hospitalization and number of patients requiring correction of INR with vitamin K.
RESULTS: The study was planned for 450 patients but it was discontinued prematurely due to a change in practice. Pocket hematoma occurred in 4 of 85 patients (5%) randomized to the bridged regimen and in 3 of 86 patients (3%) randomized to reduced-dose warfarin. One pocket hematoma in each group was severe. There were no major hemorrhages or thromboembolism within the 1-month window. Duration of hospitalization was similar in the two groups. Correction of INR the day before surgery with vitamin K had to be used for significantly more patients in the reduced-dose warfarin group (41%) than in the bridged regimen group (6%).
CONCLUSION: The reduced-dose warfarin regimen appeared to have similar safety after device implantation as interrupted warfarin with preoperative LMWH bridging. Due to premature discontinuation no firm conclusion can be drawn. The reduced-dose warfarin regimen often failed to achieve the intended preoperative INR. ClinicalTrials.gov Identifier: NCT 02094157.
PMID: 25127655 [PubMed - as supplied by publisher]