[Disease burden and clinical status of congenital heart disease combined with heart failure in China: a survey and analysis]

Objective: To investigate the disease burden, clinical characteristics and independent risk factors affecting in-hospital outcomes of children with congenital heart disease (CHD) combined with heart failure (HF) in China. Methods: (1) Descriptive study: based on the global burden of disease study 2021, available data on children under 15 years of age with CHD and HF in China from 1990 to 2021 were collected. The prevalence and trends in different age subgroups (<1 year, 1-<2 years, 2-<5 years, 5-<10 years, 10-<15 years) were analyzed, and the annual percentage change (EAPC) was estimated using linear regression. (2) Retrospective cohort study: a total of 1 062 children with CHD and HF from a multicenter study on pediatric HF in China were included. The children were divided into two groups:<2 years group and 2-<18 years group. Data on demographics, clinical features, diagnosis, treatments, and in-hospital outcomes were analyzed. Mann-Whitney U test and chi-square test were used for group comparisons.Multivariable Logistic regression was applied to identify factors influencing outcomes (in-hospital mortality and adverse cardiovascular events). Results: (1) From 1990 to 2021, the number of children with CHD and HF in China increased from 333 000 (95% uncertainty interval (UI) 271 000-405 000) to 368 000 (95%UI 296 000-459 000), a growth of 10.8% (95%UI 5.0%-16.6%). Concurrently the prevalence rate increased from 104.5 (95%UI 85.1-127.3) per 100 000 to 142.0 (95%UI 114.0-176.8) per 100 000, a growth of 35.9% (95%UI 28.7%-43.0%), with an EAPC of 1.5% (95%CI 1.2%-1.8%). Although the number of cases in the<1 year and 1-<2 years groups decreased by 41.0% and 25.6%, respectively, the prevalence in all age groups showed an upward trend:<1 year EAPC 0.6% (95%CI 0.5%-0.7%); 1-<2 years EAPC 0.9% (95%CI 0.8%-1.0%); 2-<5 years EAPC 1.2% (95%CI 1.0%-1.4%); 5-<10 years EAPC 1.5% (95%CI 1.2%-1.8%); 10-<15 years EAPC 2.1% (95%CI 1.9%-2.3%). (2) The multicenter study revealed that among 1 062 hospitalized children, 528 (49.7%) were male and 534 (50.3%) were female, with the age at admission of 5.4 (2.2,18.2) months. The majority of the children (77.9%, 827/1 062) were under 2 years of age, whereas 22.1% (235/1 062) were aged between 2-<18 years. Children with complex congenital heart defects accounted for the highest proportion (48.6%, 516/1 062), while those with isolated CHD made up 31.5% (335/1 062). Statistically significant differences were observed in several variables in demographics, clinical features, diagnosis, treatments, and outcomes between the two age groups (all P<0.05). The use of renin-angiotensin-aldosterone system inhibitors (41.1%, 436/1 062) and beta-blockers (8.7%, 92/1 062) was lower in hospitalized children with CHD and HF. Logistic regression identified complex CHD (OR=7.73, 95%CI 2.24-26.63; OR=3.17, 95%CI 1.92-5.23), pulmonary hyperperfusion (OR=2.15, 95%CI 1.01-4.18; OR=2.00, 95%CI 1.35-2.97), left ventricular ejection fraction<55% (OR=2.13, 95%CI 1.08-4.21; OR=2.80, 95%CI 1.45-5.56), arterial oxygen partial pressure (OR=0.99, 95%CI 0.98-0.99; OR=0.99, 95%CI 0.98-0.99), and serum calcium levels (OR=0.31, 95%CI 0.17-0.58; OR=0.42, 95%CI 0.28-0.62) as independent risk factors for in-hospital mortality and cardiovascular events. Conclusions: The disease burden of CHD combined with HF in China has shown a continuous upward trend from 1990 to 2021, with higher growth rates in older age groups. Complex CHD, pulmonary hyperperfusion, left ventricular ejection fraction <55%, arterial oxygen partial pressure, and serum calcium concentration are independent risk factors for in-hospital mortality and cardiovascular events.