The ABC-Death Score for Mortality Prediction in Patients With Atrial Fibrillation Undergoing Catheter Ablation

Abstract

BackgroundData on the performance of risk scores in predicting mortality risk after atrial fibrillation (AF) ablations are limited. ObjectivesThe purpose of this study was to investigate the associations of mortality with preablation biomarkers and evaluate the performance of age, biomarker, and clinical history (ABC)-death score in patients with AF undergoing catheter ablation. MethodsPatients with AF undergoing catheter ablations between 2013 and 2019 in the Chinese Atrial Fibrillation Registry were enrolled. Biomarkers associated with ABC-death score were quantified from baseline blood samples collected before AF ablation. Clinical outcomes were all-cause mortality and cardiac mortality. Discrimination, reclassification, clinical use, and calibration were further evaluated. ResultsWe identified 4,218 patients with AF undergoing catheter ablations. During a median follow-up period of 4.0 years, 119 patients died due to all causes, with 49 dying due to cardiac causes. Biomarker levels were all independently associated with an increased risk of all-cause death and cardiac death. The ABC-death score was superior to the CHA2DS2-VASc score in predicting all-cause death (C index 0.73 vs 0.63; P = 0.001) and cardiac death (C index 0.83 vs 0.71; P = 0.007). Reclassification analysis revealed significant reclassification improvements of the ABC-death score compared with the CHA2DS2-VASc (cardiac failure or dysfunction, hypertension, age ≥75 [doubled], diabetes mellitus, stroke [doubled]—vascular disease, age 65 to 74 years and sex category [female]) score. Decision curve analysis showed the greater net benefit of use of the ABC-death score. Calibration plots presented an overestimation of the observed mortality event rate by ABC-death score. ConclusionsPreablation biomarkers associated with ABC-death score were independently related to increased all-cause and cardiac mortality risk. Despite the overestimation of the event rate, the ABC-death score outperformed the CHA2DS2-VASc score in discriminating and reclassifying mortality risk, especially for cardiac mortality.