Faculty Bibliography

BACKGROUND: Although continuous-flow left ventricular assist devices (LVAD) are durable and reliable, device replacement will be inevitable in some patients. We evaluated the incidence and outcomes of pump replacement procedures with the HeartMate II (Thoratec Corporation, Pleasanton, CA) LVAD. METHODS: Data were obtained from 1,128 patients implanted from March 2005 to January 2010 with the HeartMate II during the clinical trials for bridge to transplant and destination therapy. The operative mortality associated with the replacement procedure was determined. RESULTS: The mean duration of HeartMate II support was 568 +/- 535 days (cumulative duration: 1,755 patient-years, longest: 6.5 years). A total of 72 (6.4%) patients underwent 79 LVAD replacements (0.045 events/patient-year) of which 2 were in the initial operation and 77 in separate procedures. Reasons for replacement were percutaneous lead damage (36 events, 3.0%), device thrombosis (25 events, 2.1%), infection (7 events, 0.6%), and miscellaneous other (11 events, 0.9%). The median time to pump replacement was 428 days (range 0 to 1,474). Of the 77 replacement procedures, there were 5 (6.5%) operative deaths within 30 days. The causes of death were device thrombosis, right heart failure, multisystem organ failure, and bleeding. One year after exchange (median 2.1 years after initial implant), 30% had died, 5% were transplanted, and 65% were ongoing and alive. CONCLUSIONS: HeartMate II device failure requiring pump replacement is infrequent, but when required can be done safely. These data continue to provide encouraging evidence supporting HeartMate II use for long-term circulatory support.