Enhanced Assessment of Perioperative Mortality Risk in Adults With Congenital Heart Disease

Background: In-hospital mortality is a rare, yet feared complication following cardiac surgery in adult congenital heart disease (ACHD). A risk score, developed and validated in ACHD, can be helpful to optimize risk assessment. Objectives: The purpose of this study was to assess the performance of EuroSCORE II components and procedure-related Adult Congenital Heart Surgery (ACHS) score, identify additional risk factors, and develop a novel risk score for predicting in-hospital mortality after ACHD surgery. Methods: We assessed perioperative survival in patients aged >16 years undergoing congenital heart surgery in a large tertiary center between 2003 and 2019. A risk variable–derived PEACH (PErioperative ACHd) score was calculated for each patient. Internal and external validation of the model was undertaken, including testing in a validation cohort of patients operated in a second European ACHD center. Results: The development cohort comprised 1,782 procedures performed during the study period. Re-sternotomy was undertaken in 897 (50.3%). There were 31 (1.7%) in-hospital deaths. The PEACH score showed excellent discrimination ability (area under the curve [AUC]: 0.88; 95% CI: 0.83-0.94), and performed better than the ACHS score in our population (ACHS AUC: 0.69; 95% CI: 0.6-0.78; P = 0.0003). A simple 3-tiered risk stratification was formed: PEACH score 0 (in-hospital mortality 0.2%), 1-2 (3.6%), and ≥3 (17.2%). In a validation cohort of 975 procedures, the PEACH score retained its discriminative ability (AUC: 0.75; 95% CI: 0.72-0.77) and was well calibrated (Hosmer-Lemeshow chi-square goodness-of-fit P = 0.55). There was agreement in expected and observed perioperative mortality between cohorts. Conclusions: The PEACH score is a simple, novel perioperative risk score developed and validated specifically for ACHD patients undergoing cardiac surgery.