Abstract 16163: Low Dose Alteplase for Treatment of Pacemaker Lead Associated Thrombosis

Abstract

Multiple previously published case reports highlighted the thromboembolic risks associated with permanent transvenous pacemaker leads. Even though mostly clinically silent, pacemaker lead associated thrombosis has been linked to fatal outcomes via pulmonary or paradoxical embolism in the case of large mobile RA or RV thrombi formation. There is a lack of consensus on the optimal strategy for managing this condition. Oral and IV anticoagulation, thrombolysis, surgical and percutaneous thrombectomy have been attempted previously with mixed results. A 72 year old gentleman with a history of CAD requiring PCI, paroxysmal atrial fibrillation, and AV node ablation with subsequent biventricular pacemaker implant was admitted to our hospital with a few weeks of worsening dyspnea, now present at rest. Surface echocardiogram showed multiple mobile echo densities in the right ventricle and right atrium, attached to the pacemaker leads, confirmed by TEE, most likely thrombi. The venous duplex was positive for right lower extremity DVT. Bilateral pulmonary emboli with mild right-sided heart strain were noted on CTA chest. The patient was initially treated with IV unfractionated heparin. We subsequently decided to start low-dose tPA infusion for 24 hrs, similar to current off-label protocols for mechanical prosthetic valves or bioprosthetic valve thrombosis. After an initial IV bolus of 5 mg, 1 mg/hour of alteplase was continued for 24 hours. Our team has decided to use percutaneous thrombectomy as a last resort.Follow-up ECHO immediately post tPA infusion showed complete thrombi resolution. The patient was asymptomatic at this point. He was discharged the following day on Lovenox and Coumadin. To our knowledge, this is the first case demonstrating complete resolution of pacemaker lead-associated thrombi by using a 24 hr low dose tPA infusion in addition to IV anticoagulation. This can be entertained as a simple conservative initial strategy in stable patients with pacemaker lead/catheter-associated intracardiac thrombi.