Capturing Adult Congenital Heart Disease: Framework for Development of an ACHD Mortality Risk Model

Abstract Background As a formative step toward development of adult congenital heart disease (ACHD) risk-adjusted metrics, we describe the STS ACHD population, procedural frequency, and early mortality. Methods Adults ( > 18 years) with CHD (2014-2019) were identified in the STS Adult Cardiac Surgery (ASCD) and the Congenital Heart Surgery (CHSD) Databases. Following deduplication, variable mapping, data concatenation, and harmonization of pre-procedure factors, procedures were grouped and unadjusted mortality catalogued for overall cohort and the cohort excluding patients with isolated bicuspid aortic valve (BAV). Results Among 171,186 ACSD and 18,281 CHSD records, 152,731 unique records met inclusion criteria. Twenty-eight congenital diagnoses accounted for 86% of the overall cohort, and prevalence of ACHD increased over the study timeframe. ACHD patients underwent operations to treat both acquired and CHD. Most common procedures overall and after excluding isolated BAV were: aortic valve replacement (AVR), ascending aortic surgery, and coronary artery bypass grafting (CABG). After excluding isolated BAV, major procedure combinations occurred in 46% (31% had 2 and 3% > 4 major procedures) and most prevalent combinations included: AVR + CABG (n=2,352), AVR + subaortic stenosis repair (n=1,481) and AVR + ascending aortic surgery (n=1,239). Unadjusted 30-day mortality was procedure dependent, 2.8% overall and 3.6% with isolated BAV excluded. Conclusions The ACHD surgical population is heterogenous, and patients undergo surgery for CHD-related and adult/acquired procedure combinations. Early mortality is variable and influenced by surgical complexity. Excluding isolated BAV patients and developing procedure-based ACHD mortality risk models may be ideal but will require empirically-derived grouping and collaboration.