The authors conclude from their findings that there is a net clinical benefit in favour of a strategy of forgoing bridging, as compared with perioperative bridging with low-molecular-weight heparin, in patients requiring temporary interruption of their warfarin treatment for an elective procedure. These results are consistent with previous non-randomised comparisons of these strategies.
The rationale for the use of bridging anticoagulation therapy has been based on the assumption that the associated higher bleeding risk would be offset by a lower risk of perioperative arterial thromboembolism (ATE). The findings of this and previous research suggest the perioperative risk of ATE in patients with atrial fibrillation during interruption of warfarin treatment may have been overstated and may not be mitigated by bridging anticoagulation.
The authors do however go on to acknowledge the limitations of their study – for example the population did not include patients undergoing procedures associated with a higher risk of ATE (e.g. major cancer surgery) and patients with mechanical heart valves were excluded. In addition the overall rate of ATE was lower than expected, and therefore it may not have been adequately powered to detect any benefit associated with bridging (the selected non-inferiority margin [1%] turned out to be large in relation to the actual observed event rate).