346 - Patients with Prosthetic Valves and Need for Left Ventricular Assist Device

Abstract

Introduction: The use of left ventricular assist device (LVAD) in patients with prosthetic valves has been a subject of debate. The risk of thromboembolic (TE) events remains a concern especially if anticoagulation had to be interrupted in case bleeding occurs. Case Report: We report a case of a 63-year-old female with end-stage heart failure awaiting a heart transplant. She was admitted to the hospital for worsening chronic heart failure and was inotrope dependent. While awaiting heart transplant, a decision was made to implant a left ventricular assist device (LVAD) as a bridge to transplant. She had a mechanical mitral valve (mMVR) which was exchanged to a bioprosthetic valve at the time of LVAD implantation. Post-operative course was complicated by bleeding while she was on anticoagulation but she survived. Objectives and methods: We searched PubMed for case studies of patients with LVAD having bioprosthetic valves. We found retrospective studies and case reports from 1982 to 2010 on patients with LVAD and prosthetic valves. Only patients with permanent LVAD were analyzed (n = 37). These patients were further subgrouped into bioprosthetic mitral valve replacement (bMVR) and aortic valve replacement (bAVR); mechanical mitral valve replacement (mMVR) and aortic valve replacement (mAVR); and combined mechanical and bioprosthetic MVR and AVR. Moreover, we analyzed different eras of anticoagulation. Outcomes analyzed were TE events, bleeding and death. Results: Majority patients were bridged to warfarin as their anticoagulation regimen. Nine patients with mMVR had a mean LVAD support time of 168.2 days. Four patients with bMVR had a mean LVAD support time of 229.6 days. No clinical TE events or bleeds were reported in both these subgroups. Seven patients with mAVR had a mean LVAD support time of 47.57 days. Thrombus was found in one of the explanted heart, but no clinical TE events were reported. One patient had bleed. Eight patients with bAVR had a mean support time of 223.7 days. Thrombus was found underneath the aortic valve of the explanted heart of one patient. No bleeding or clinical TE events were noted. In the combination group, mean LVAD support time was 96.3 days. One patient had a bleeding complication. One patient had a TE event. Overall mortality was high in all subgroups ranging from 25% to 37.5% unrelated to TE event or bleed. Conclusion: Our analysis showed no significant TE events or bleeding complications in these patients. LVAD in patients with pre-existing prosthetic valves is worth consideration given the shortage of heart donors. We prefer exchanging the mechanical valve to a bMVR as it carries a lesser risk of TE events. However, one should be mindful of the overall high mortality rate in these patients. Larger studies need to be conducted to confirm these findings.