Clinical characteristics and risk factors of cardiac involvement in pediatric immunoglobulin A vasculitis: A 7-year retrospective study from a single tertiary medical center.

Immunoglobulin A vasculitis(IgAV) is the most common form of systemic vasculitis affecting children. To date, cardiac involvement in pediatric IgAV has not been fully investigated and its prevalence may be underestimated. This study aims to reveal the clinical and laboratory characteristics of cardiac involvement in pediatric IgAV and further determine its risk factors. A total of 1451 children with IgAV were recruited between January 2016 and December 2022. According to the severity of cardiac involvement, the patients were divided into the myocarditis/suspected myocarditis group, cardiac abnormalities group, and non-cardiac involvement group. Demographic, clinical, and laboratory characteristics were retrospectively extracted from the individual data collected in the medical records. Among the 1451 pediatric IgAV patients, 179 (12.3%) were identified with cardiac involvement, including 154 (10.6%) with cardiac abnormalities and 25 (1.7%) with myocarditis/suspected myocarditis. Cardiac involvement in pediatric IgAV mainly manifested as elevated cardiac biomarker levels (n = 162), electrocardiogram abnormalities (n = 46), and echocardiogram/chest X-ray abnormalities (n = 15); however, cardiac-related symptoms were only observed in 15.1% of patients with cardiac involvement. Multivariate analysis demonstrated that interval from disease onset to diagnosis > 7 days (OR, 2.157; 95% CI, 1.523-3.057; p < 0.001), IgAV with multi-organ involvement (OR, 1.806; 95% CI, 1.242-2.627; p = 0.002), and elevated D-dimer levels (OR, 1.939; 95% CI, 1.259-2.985; p < 0.001) were independent risk factors for cardiac involvement in pediatric IgAV. The length of hospital stay was significantly longer in the myocarditis/suspected myocarditis group compared with the other two groups (p < 0.05).     Conclusion: This study suggests that cardiac involvements in pediatric IgAV is non-negligible, and cardiac involvement is associated with interval from disease onset to diagnosis > 7 days, IgAV with multi-organ involvement, and elevated D-dimer levels. Severe cardiac involvement may affect the prognosis of pediatric IgAV. What is Known: • Immunoglobulin A vasculitis (IgAV) is the most common form of systemic vasculitis affecting children and adolescents, which exhibits diverse clinical manifestations. Cases of severe IgAV complicated by cardiac involvement have been anecdotally reported. What is New: • The present study suggests that cardiac involvements in pediatric IgAV is non-negligible, and cardiac involvement is associated with interval from disease onset to diagnosis > 7 days, IgAV with multi-organ involvement, and elevated D-dimer levels. Severe cardiac involvement may affect the prognosis of pediatric IgAV.