Multicenter cohort analysis of cardiac amyloidosis patients treated with heart transplant

Introduction and objectives: To describe the clinical characteristics of patients with cardiac amyloidosis who have undergone heart transplantation (HT). Methods: This retrospective multicenter study involving 14 referral centers included 113 patients with cardiac amyloidosis who underwent HT: 57 with transthyretin amyloidosis (ATTR) (22 with wild-type ATTR and 35 with variant ATTR) and 56 with light chain amyloidosis (AL). Results: Compared with patients with ATTR, patients with AL amyloidosis showed more severe hemodynamic compromise before HT, with a lower cardiac index (1.7 L/min/m2 [interquartile range, 1.4-2.0 L/min/m2] vs 1.9 L/min/m2 [interquartile range, 1.6-2.4 L/min/m2]; P = .027) and higher right atrial pressure. Post-transplant infections occurred in 23 patients with ATTR (40%) and 24 with AL (43%). New-onset neuropathy occurred in 11% of patients, while neuropathy progression was more frequent in ATTR compared with AL (23% vs 7.1%; P = .044). Median follow-up was 4.6 years in ATTR and 5.4 years in AL. Five-year survival was similar in both groups (77% in AL vs 83% in ATTR). Sepsis was the leading cause of death (n = 11, 29% of deaths). Among patients with ATTR, 9 received tafamidis before HT and 7 after HT. Eight patients with ATTR received patisiran post-HT (1 pre-HT), and 3 received diflunisal post-HT. In AL, 70% received bortezomib-based therapy while 28% received daratumumab-based therapy. In AL, hematologic responses improved after HT, with the complete response rate increasing from 42% before HT to 54% after HT. Conclusions: HT is an effective treatment for carefully selected patients with cardiac amyloidosis, with comparable unadjusted survival between AL and ATTR. These findings warrant confirmation in prospective studies.