Cardiac Resynchronization Therapy Device Implantation in Patients with Therapeutic International Normalized Ratios

Background: Many patients who need cardiac resynchronization therapy (CRT) require chronic anticoagulation. Current guidelines recommend discontinuation of warfarin and the initiation of anticoagulant “bridging” therapy during these procedures. We evaluated the safety of CRT‐device (CRT‐D) implantation without interruption of warfarin therapy. Methods: A total of 123 consecutive patients requiring CRT‐D therapy were enrolled, 49 identified as high risk for thromboembolic events who received either intravenous heparin, low molecular weight heparin, or warfarin therapy. The control group comprised 74 patients with low risk of thromboembolic events who required only cessation of warfarin perioperatively. Patients were evaluated at discharge and 15 and 30 days postoperatively for pocket hematomas, thromboembolic events, and bleeding. Patients’ length of stay was also catalogued. Results: Patients in the bridging arm had a significant increase in the rate of pocket hematomas (4.1%[control] vs 5.0%[warfarin] vs 20.7%[bridging], P = 0.03) and subsequent longer length of stay (1.6 ± 1.6 [control] vs 2.9 ± 2.7 [warfarin] vs 3.7 ± 3.2 [bridging], P < 0.001). Hematoma formation postoperatively was not different among patients undergoing an upgrade procedure versus those without preexisting cardiac rhythm devices (12% vs 6.2%, P = NS). Patients with a prosthetic mechanical mitral valve had a higher incidence of pocket hematoma formation (1.8% vs 20%, P = 0.03). Conclusions: Our findings suggest that implantation of CRT‐Ds without interruption of warfarin therapy in patients at high risk of thromboembolic events is a safe alternative to routine bridging therapy. This strategy is associated with reduced risk of pocket hematomas and shorter length of hospital stay. (PACE 2010; 400–406)