Bivalirudin use during radiofrequency catheter ablation procedures in two patients with a history of heparin-induced thrombocytopenia.

Current guidelines recommend using bivalirudin, a direct thrombin inhibitor,as a preferred alternative to unfractionated heparin in patients with heparin induced thrombocytopenia (HIT) for percutaneous coronary intervention, as well as for cardiac and vascular surgery. Anticoagulation during radiofrequency catheter ablation (RFA) procedures may be another potential use for bivalirudin in the setting of HIT. Radiofrequency catheter ablation procedures involving left atrial or left ventricular access are increasingly employed as a method to treat cardiac arrhythmias. Because stroke risk is a serious complication of RFA, anticoagulation is required during this procedure. We describe the first report, to our knowledge, of successful use of bivalirudin anticoagulation during RFA procedures in two patients with a history of clinically diagnosed HIT that precluded the use of unfractionated heparin or low-molecular-weight heparin. One of the patients underwent RFA for ventricular tachycardia, the other for pulmonary vein isolation for the treatment of atrial fibrillation. In both patients, bivalirudin was administered as a 0.75-mg/kg intravenous bolus, followed by a 1.75-mg/kg/hour infusion.Activated clotting time (ACT) was measured after the initial bolus in each patient. However, no dosage adjustment was made based on the ACT, and the infusion rate of bivalirudin remained fixed during the procedures. Both procedures were completed without any embolic events. No bleeding or clotting events were noted; one patient experienced minor access site oozing that was not felt to be clinically important. Bivalirudin is a therapeutic option for anticoagulation during left-sided catheter RFA procedures in patients with a history of HIT.