THE BOLOGNA’ SCORE: A NOVEL RISK STRATIFICATION TOOL FOR ADULT WITH CONGENITAL HEART DISEASE UNDERGOING HEART TRANSPLANTATION

Background: Grown-up congenital heart disease patients (GUCHs) represent an expanding population characterized by higher early post heart transplant mortality compared with the population without congenital heart disease. Aim of our study was to identify potential preoperative risk factors and to develop a risk-score that could complement the pre-transplant assessment of GUCHs. Methods: From 2009 to 2024, 33 GUCHs underwent heart transplantation. Spearman’s correlation coefficient or Kendall’s tau were used to examine bivariate relationship between pre-transplant variables and mortality. Variables were explored using a correlation matrix: positive or negative correlations greater than 0.30 in absolute value were highlighted. ROC analysis was performed to evaluate predictive ability of the variables and score. Optimal cut-offs were identified by Youden’s J index. Moreover, ROC analysis was used to compare our score with the score proposed by Seese et al. Results: Seven predictors resulted associated with mortality: sodiemia (p=0.024), haemoglobin (p=0.013), haematocrit (p=0.007), FEV1 (p=0.068), systolic pulmonary artery pressure (PAP, p=0.037), diastolic-PAP (p=0.011) and mean-PAP (p=0.013). Overall survival in patients with Bologna’ score greater than 3 was 75%, 63% and 63%, while in patients with Bologna’ score lower than 3 was 88%, 83% and 83% at 1,5 and 10 years respectively(log-rank=0.037). ROC analysis comparing the two scores revealed a better accuracy of the Bologna score (AUC=0.730) than Seese’s score (AUC=0.488). Conclusions: Mortality in GUCHs is not only influenced by cardiac pathology but by the patient’s overall compensation picture. The developed population-specific risk-score showed to be predictive for mortality and could be used in the pre-transplant evaluation of GUCHs.