From the Literature


Published: Jul 2015

Bleeding, recurrent venous thromboembolism, and mortality risks during warfarin interruption for invasive procedures.
Clark NP, Witt DM, Davies LE, et al.
JAMA Intern Med 2015;175:1163-1168.
Pub Med
NATA rating :


D. Faraoni


Preoperative management of patients treated with vitamin K antagonists who require elective surgical procedures has been debated over the last decade. In such situations, the balance between the procedure-related bleeding risk and the risk for recurrent thromboembolic complications should be carefully evaluated.

Clark et al. performed a retrospective cohort study including 1,178 patients who were receiving warfarin therapy for secondary prevention of venous thromboembolism (VTE) in whom warfarin was interrupted before invasive diagnostic or surgical procedures. The authors compared the incidences of perioperative bleeding and recurrent VTE when a bridging strategy was used or not.

Among the 1,178 patients who unbderwent a total 1,812 invasive procedures, the 30-day rate of clinically relevant bleeding was significantly higher in the bridging group (2.7%) compared with the control group (0.2%) (hazard Ratio: 17.2, 95%CI: 3.9-75.1, P = 0.01). Bleeding complications occurred most frequently in pacemaker or implantable cardiac defibrillator, urologic, and vascular procedures. On the other hand, the use of bridging therapy was not associated with any improvement in the incidence of recurrent VTE, with an incidence of only 0.2% (3/1,257) in the control group versus 0% (0/555) in the bridging group.

This large cohort study confirms that preoperative bridging therapy in patients receiving warfarin for secondary VTE prevention is associated with a significant increase in the incidence of bleeding complications without any benefit in terms of recurrent VTE. In this context, warfarin interruption may be safely considered without bridging. Further studies are needed to better define the benefit-to-risk balance in high-risk patients (e.g. those with atrial fibrillation or a prosthetic valve).

- David Faraoni