RESUMEN
OBJECTIVE: This study aims to investigate the trends, outcomes, and risk factors for mortality after redo orthotopic heart transplantation. METHODS: The United Network for Organ Sharing registry was used to identify adult orthotopic heart transplantation recipients from 2000 to 2020 and stratify into primary and redo cohorts. Five-year post-transplant survival was compared between 2 propensity-matched cohorts. Multivariable modeling was performed to identify risk-adjusted predictors of redo post-transplant mortality, both conditional and nonconditional on shorter-term survival. RESULTS: A total of 40,711 recipients were analyzed, 39,657 (97.4%) primary and 1054 (2.6%) redo. Redo recipients had a lower median age and were more frequently bridged with intravenous inotropes, intra-aortic balloon pump, or extracorporeal membrane oxygenation (all P < .05). One- and 5-year survivals were lower after redo orthotopic heart transplantation (90.0% vs 83.4% and 77.6% vs 68.6%, respectively) and remained lower after comparing 2 propensity-matched cohorts. Multivariable modeling found factors such as increasing donor age and graft ischemic times, along with pretransplant mechanical ventilation and blood transfusion, to negatively affect 90-day survival. Contingent on 1-year survival, donor factors such as hypertension (hazard ratio, 1.51; 95% confidence interval, 1.15-2.00, P = .004) and left ventricular ejection fraction less than 50% (hazard ratio, 2.22, 95% confidence interval, 1.16-4.24, P = .016) negatively affected survival at 5 years. CONCLUSIONS: Although infrequently performed, redo orthotopic heart transplantation remains associated with worse post-transplant outcomes compared with primary orthotopic heart transplantation. Although several high-risk features were identified to affect post-retransplant outcomes in the acute perioperative period, donor characteristics such as hypertension and decreased ejection fraction continue to have lasting negative impacts in the longer term.
Asunto(s)
Trasplante de Corazón , Función Ventricular Izquierda , Adulto , Humanos , Volumen Sistólico , Resultado del Tratamiento , Trasplante de Corazón/efectos adversos , Factores de Riesgo , Estudios RetrospectivosRESUMEN
After orthotopic heart transplantation (OHT), the allograft undergoes characteristic alterations in myocardial structure, including hypertrophy, increased ventricular stiffness, ischemia, and inflammation, all of which may decrease overall graft survival. Methods to quantify these phenotypes may clarify the pathophysiology of progressive graft dysfunction post-OHT. We performed cardiac magnetic resonance (CMR) with T1 mapping in 26 OHT recipients (mean age 47 ± 7 years, 30 % female, median follow-up post-OHT 6 months) and 30 age-matched healthy volunteers (mean age 50.5 ± 15 years; LVEF 63.5 ± 7 %). OHT recipients had a normal left ventricular ejection fraction (LVEF 65.3 ± 11 %) with higher LV mass relative to age-matched healthy volunteers (114 ± 27 vs. 85.8 ± 18 g; p < 0.001). There was no late gadolinium enhancement in either group. Both myocardial extracellular volume fraction (ECV) and intracellular lifetime of water (τic), a measure of cardiomyocyte hypertrophy, were higher in patients post-OHT (ECV: 0.39 ± 0.06 vs. 0.28 ± 0.03, p < 0.0001; τic: 0.12 ± 0.08 vs. 0.08 ± 0.03, p < 0.001). ECV was associated with LV mass (r = 0.74, p < 0.001). In follow-up, OHT recipients with normal biopsies by pathology (ISHLT grade 0R) in the first year post-OHT exhibited a lower ECV relative to patients with any rejection ≥2R (0.35 ± 0.02 for 0R vs. 0.45 ± 0, p < 0.001). Higher ECV but not LVEF was significantly associated with a reduced rejection-free survival. After OHT, markers of tissue remodeling by CMR (ECV and τic) are elevated and associated with myocardial hypertrophy. Interstitial myocardial remodeling (by ECV) is associated with cellular rejection. Further research on the impact of graft preservation and early immunosuppression on tissue-level remodeling of the allograft is necessary to delineate the clinical implications of these findings.