Patterns of Incidence Rates of Cardiac Complications in Patients With Congenital Heart Disease

Background: This study aimed to evaluate age at the first onset of cardiac complications and variation of frequency of complications between different congenital heart defects. Methods: The analysis included participants of the Swiss Adult Congenital Heart Disease Registry (SACHER). For this study, cardiac complications up to the time of inclusion in SACHER were analysed. Complications included atrial fibrillation, atrial flutter, supraventricular tachycardia, ventricular tachycardia, complete heart block, heart failure, stroke, endocarditis, myocardial infarction, and pulmonary hypertension. Incidence rates (IR; incidence rate per 1000 patient-years) for different age categories and diagnosis groups were analysed. Results: Of 2731 patients (55% male, mean age 34 +/- 14 years, 92,349 patient-years), a total of 767 (28%) had experienced at least 1 cardiac complication. The majority of complications (550; 72%) occurred in adulthood (> 18 years). Apart from perioperative stroke (IR: 1.77 in age group <= 4 years) and complete heart block (IR: 2.36 in age group <= 4 years), IR were much lower in childhood (IR < 1 for all complications between 5 and 17 years). Incidence of cardiac complications increased during adult life with highest IR for atrial fibrillation and atrial flutter in the age group >= 50 years (IR: 17.6 and 9.7, respectively). There were important variations of the distribution of complications among different diagnosis groups. Conclusions: Cardiac complications are frequent in congenital heart disease. Apart from perioperative stroke and complete heart block, IR are low in childhood but the incidence increases during adult life. These data underscore the need of lifelong follow-up and may help for better allocation of resources maintaining follow-up.