Low Rate of Allosensitization Associated with the Syncardia Total Artifical Heart and the Heartmate II LVAD

Abstract

Purpose Significant rates of allosensitization have been associated with the use of durable mechanical circulatory support devices as a bridge to heart transplantation. Continuous flow devices have been demonstrated to have lower rates of allosensitization compared to older pulsatile devices. However, this is confounded by other factors such as the increased utilization of leuko-reduced blood transfusions. The aim of this study was to examine contemporary allosensitization rates in the Syncardia total artificial heart (TAH) and the Heartmate II LVAD (HMII). Methods and Materials A retrospective analysis of TAH and HMII implants performed at our institution between 10/2009 and 9/2012. During this time period, our blood bank switched to universal use of leuko-reduced blood products. Sensitization was defined by a cPRA > 10%. Sensitization following device implant was compared by Fisher’s exact test. Results Over the 3 year period, 42 TAH and 86 HMII implants were performed. PRA data post implantation was available for 36 TAH and 48 HMII implants. 7 (19%) TAH and 6 HMII (13%) were found to be sensitized following device implant (p=0.54). Of the 7 sensitized TAH patients, 5 were known to be sensitized prior to implantation. Of the 2 patients who developed sensitization following TAH implant, one was in the setting of a failed heart transplant. Of the 6 sensitized HMII patients, 2 were known to be sensitized prior to implantation. Baseline PRA data was unavailable for the other 4 patients. Of the 12 sensitized patients (one patient underwent both HMII and TAH implants), 4 have been transplanted, 2 died prior to transplantation, and 6 remain on device support. Conclusions Contemporary rates of allosensitization are lower than previously reported. Multiple factors affect allosensitization. Significant differences in allosensitization due to device type were not seen.