The report of Douketis et al1 on a cohort of patients at increased risk for arterial thromboembolism who require temporary interruption of warfarin sodium therapy and received bridging anticoagulation with low-molecular-weight heparin (LMWH) in the periprocedural period deserves comment. Of the 650 patients included, 414 patients could in fact have been classified as having low risk for thromboembolism2 (306 patients with atrial fibrillation without concomitant heart disease and 108 patients with a single mechanical heart valve in the aortic position). In this relatively low-risk group, complete withholding of perioperative anticoagulation rather than administration of LMWH would reduce the incidence of bleeding complications without introducing an unacceptable high risk for thromboembolism. Therefore, the prevention of thromboembolism with the administration of LMWH in this group of patients might be unnecessary. To optimize periprocedural anticoagulation in patients who receive lifelong anticoagulation with warfarin, a randomized controlled trial comparing different periprocedural anticoagulation protocols is needed.
van Dongen CJ, Vink R, Levi M. Low-Molecular-Weight Heparin as Bridging Anticoagulation. Arch Intern Med. 2004;164(22):2500-2509. doi:10.1001/archinte.164.22.2500-a