Thromboembolic prophylaxis protocol with warfarin after radiofrequency catheter ablation of infarct-related ventricular tachycardia.

Abstract

Ablation in the left ventricle (LV) is associated with a risk of thromboembolism. There are limited data on the use of specific thromboembolic prophylaxis strategies postablation. We aimed to evaluate a thromboembolic prophylaxis protocol after ventricular tachycardia (VT) ablation. The index procedures of 217 patients undergoing ablation for infarct-related VT with open irrigated-tip catheters were included. Patients with large LV endocardial ablation area (>3cm between ablation lesions) were started on low-dose, slowly escalating unfractionated heparin (UFH) infusion 8hours after access hemostasis, followed by 3months of anticoagulation. Patients with less extensive ablation were treated only with antiplatelet agents postablation. Postablation bridging anticoagulation was used in 181 (83%) patients. Of them, 11 (6%) patients experienced bleeding events (1 required endovascular intervention) and 1 (0.6%) experienced lower extremity arterial embolism requiring vascular surgery. Systemic anticoagulation was prescribed in 190 (89%) of 214 patients discharged from the hospital (warfarin in 98%), while the rest received single- or dual-antiplatelet therapy alone. Patients treated with an anticoagulant had significantly longer radiofrequency time compared to patients treated with antiplatelet agents only. One (0.5%) of the patients treated with oral anticoagulation experienced major bleeding 2 weeks postablation. No thromboembolic events were documented in either the anticoagulation or the "antiplatelet only" group postdischarge. A slowly escalating bridging regimen of UFH, followed by 3months of oral anticoagulation, is associated with low thromboembolic and bleeding risks after infarct-related VT ablation. In the absence of extensive ablation, antiplatelet therapy alone is reasonable.