Implantation of pacemakers and implantable cardioverter defibrillators in orally anticoagulated patients.

The safety of pacemaker and defibrillator implantations in orally anticoagulated patients using standard techniques has not been thoroughly evaluated. This article describes a prospectively collected experience in such patients. Patients presenting for device implantation who were treated with warfarin were allowed to continue therapy provided that the INR was < 3.5. Implantations involved cannulation of the left axillary vein. Except for defibrillator leads, 7 Fr introducers were used, and all were leads actively fixated. The study included 47 patients who underwent implantation of permanent pacemakers (n = 39), defibrillators (n = 5), or biventricular pacemakers (n = 3). The mean INR was 2.3. The primary indication for anticoagulation was a mechanical cardiac prosthesis in 11 (24%) patients. Atrial fibrillation was present in 33 patients. There were no instances of major bleeding or hematomas requiring evacuation. One patient had a small soft hematoma, which resolved spontaneously. At 6 weeks, all patients had well-healed scars with satisfactory pacing and sensing thresholds. In experienced centers, patients requiring treatment with warfarin may undergo implantation of pacemakers or defibrillators with minimal risk despite continuation of anticoagulation.