Outcomes of Heart Transplantation (HT) in Patients with Total Artificial Heart (TAH) as Bridge to Transplantation (BTT)

Abstract

<h3>Purpose</h3> Majority of patients who are BTT with a TAH are INTERMACS profiles 1 & 2. Few center-based reports document outcomes after HT for patients with TAH, which range from inferior to similar survival compared to a non-BTT population. We report the outcomes of HT after TAH placement from a national registry. <h3>Methods</h3> This analysis examined HT outcomes in patients BTT with TAH compared to BiVAD and LVAD, in a linked cohort from the INTERMACS & SRTR databases (2006-15). Survival was determined for LVAD vs BiVAD vs TAH BTT cohort. Risk factors for mortality were explored using multi-phase hazard modeling. <h3>Results</h3> Among 3143 adults supported with MCS at HT and linked in the INTERMACS & SRTR databases, there were 176 TAH, 2762 LVAD and 205 BiVAD. TAH group mean age: 48.6 ± 13.1 years; males 86.4%; diagnosis: DCM 69.9%, ICM 19.3%; donor mean age: 30.2± 10.8 years. Donor age (<19, 19 - 40, >40 years) did not affect survival in the HT TAH (p = 0.2). Post-HT survival without risk adjustment with each MCS in Fig. After risk adjustment with multi-phase hazard model, LVAD alone was associated with less post-HT risk (HR=0.55 [95%CI]). TAH was not an independent risk factor compared to BiVAD, constant phase. HT survival at 1, 36, 60 months in TAH BTT vs ISHLT Registry was 89.2%, 69.8%, 61.3% vs 92%, 63.6%, 57.3%, respectively. Post-HT complications were LVAD vs BiVAD vs TAH: rejection 1^st year 21.2%, 26.4%, 15.5% (p=0.1); stroke 3.4%, 5.9%, 5.7% (p=0.07); infection 15.3%, 27.3%, 21.6% (p<0.0001). Kidney transplant (KT) rates were 1.9%, 2.9%, 12.5% respectively. <h3>Conclusion</h3> The LVAD, TAH and BTT cohorts show similar post-HT survival compared to the ISHLT. Donor age did not influence TAH BTT survival. TAH cohort had a higher incidence of H-KT. After risk adjustment: TAH & BiVAD post-HT survival were similar. Post-HT complications are similar among MCS groups, except higher infection risk with BiVAD. In patients with BiV failure, TAH is an option, with lower post-HT infection compared to BiVADs.