Improved survival in patients with acute myocarditis using external pulsatile mechanical ventricular assistance

Background: Acute myocarditis remains a disease with a variable clinical co urse, from full ventricular recovery to complete heart failure; to date, fe w cases have been reported that describe the efficacy of temporary mechanic al ventricular assistance for its treatment. Methods: We evaluated the voluntary world registry with the use of an exter nal pulsatile ventricular assist device (the ABIOMED BVS 5000 [BVS]) for ac ute myocarditis to determine the impact of mechanical ventricular assistanc e on outcome. Variables analyzed included patient demographics, serum chemi stries, and overall hemodynamics prior to BVS, while on BVS support, and af ter BVS explanation. Postoperative parameters included re-operation, bleedi ng, respiratory failure, renal failure, and infections, neurologic, or embo lic events. Results: Eighteen patients in the ABIOMED world registry underwent BVS impl antation for myocarditis; 11 (61.1%) had complete pre-operative and hemodyn amic data for analysis. Patients were supported for 13.2 +/- 17.0 days, aft er which time 7 (63.6%) patients survived to explanation of the device and 2 (18.2%) underwent transplantation. Elevated admission serum chemistries b lood ureanitrogen [BUN], creatinine, transaminases) and hemodynamics (centr al venous pressure [CVP], mean pulmonary arterial pressure [PAP], pulmonary capillary wedge pressure [PCW], cardiac index [CI], all normalized during the period of device support. Estimated ejection fractions in the 7 explant ed patients ranged between 50 to 60% at routine evaluation 3 years after de vice removal. Conclusions: Temporary mechanical ventricular assistance represents an effi cacious therapy for acute myocarditis in patients with hemodynamic decompen sation despite maximal medical therapy. Failure to achieve full ventricular recovery while on device support still allows for other surgical alternati ves, including implantation of a long-term implantable ventricular assist d evice, or cardiac transplantation.