Utility of the IMPACT score for predicting heart transplant mortality. Analysis on a contemporary cohort of the Spanish Heart Transplant Registry
Carlos Ortiz-Bautista 1 2 , Javier Muñiz 2 3 , Luis Almenar-Bonet 2 4 , María G Crespo-Leiro 2 5 , José M Sobrino-Márquez 6 , Marta Farrero-Torres 7 , María D García-Cosio 2 8 , Beatriz Díaz-Molina 9 , Isabel Zegrí-Reiriz 2 10 , Francisco González-Vilchez 11 , Zorba Blázquez-Bermejo 1 2 , Amador López Granados 12 , Manuel Gómez-Bueno 2 13 , Luis de la Fuente-Galán 2 14 , Teresa Blasco-Peiró 15 , Iris P Garrido-Bravo 2 16 , Elena García-Romero 17 , Gregorio Rábago Juan-Aracil 18 , Luis García-Guereta 19 , Juan F Delgado-Jiménez 2 8
Introduction and objectives: The Index for Mortality Prediction After Cardiac Transplantation (IMPACT) score was derived and validated as a predictor of mortality after heart transplantation (HT). The primary objective of this work is to externally validate the IMPACT score in a contemporary Spanish cohort.
Methods: Spanish Heart Transplant Registry data were used to identify adult (>16 years) HT patients between January 2000 and December 2015. Retransplantation, multiorgan transplantation and patients in whom at least one of the variables required to calculate the IMPACT score was missing were excluded from the analysis (N = 2,810).
Results: Median value of the IMPACT score was 5 points (IQR: 3, 8). Overall 1-year survival rate was 79.1%. Kaplan-Meier 1-year survival rates by IMPACT score categories (0-2, 3-5, 6-9, 10-14, ≥ 15) were 84.4%, 81.5%, 79.3%, 77.3% and 58.5% respectively (Log-Rank test: p<0.001). Performance analysis showed a good calibration (Hosmer-Lemeshow chi-square for one year was 7.56; p = 0.47) and poor discrimination ability (AUC-ROC 0.59) of the IMPACT score as a predictive model.
Conclusions: In a contemporary Spanish cohort, the IMPACT score failed to accurately predict the risk of death after HT.
CITA DEL ARTÍCULO Clin Transplant. 2022 Sep;36(9):e14774. doi: 10.1111/ctr.14774. Epub 2022 Jul 21.