The Evolving Long-Term Outcome of Heart Transplantation in Amyloid Patients

Abstract

Purpose Both amyloid light chain (AL) amyloidosis and transthyretin-related (TTR) amyloid are expanding indications for heart transplantation (HTx). In the past, AL amyloid, in particular, had been a contraindication to HTx given its systemic nature and the increased risk for mortality. Modern treatments including proteasome inhibitors have allowed amyloid patients to receive heart transplants at an increasing rate. We sought to assess long-term post-transplant outcome in amyloid patients in the current era. Methods Between 2010 and 2015, we assessed 27 patients (5 AL, 10 TTR-wildtype (wt), 12 TTR-mutant (m)) who underwent heart transplant for cardiac amyloidosis at our single center. A non-amyloid restrictive cardiomyopathy control population was included (n=18). Endpoints included 3-year outcomes including survival, freedom from CAV (as defined by stenosis ≥ 30% by angiography), freedom from non-fatal major adverse cardiac events (NF-MACE: myocardial infarction, new congestive heart failure, percutaneous coronary intervention, implantable cardioverter defibrillator/pacemaker implant, stroke), and freedom from any-treated rejection, acute cellular rejection, and antibody-mediated rejection. Results There was no significant difference between the AL amyloid, TTR-wt, TTR-m, and restrictive non-amyloid patients with respect to 3-year survival and 3-year freedom from CAV, NF-MACE, and rejection (see table). Endomyocardial biopsies post-transplant did not show amyloid. (see Table) Conclusion In the current era, both AL and TTR amyloid patients have acceptable mid-term outcome after heart transplantation. Larger numbers and longer followup are needed to confirm these findings.