Serum N‐terminal atrial natriuretic peptide in adult patients late after surgical repair of atrial septal defect

Background: The purpose of surgical closure of atrial septal defect (ASD) is to relieve the cardiovascular system from a haemodynamic burden. Excessive amounts of atrial peptides are released in congestive heart failure, valvular diseases and congenital heart diseases. Aims: To examine whether patients after surgical repair of ASD have higher concentrations of N‐terminal atrial natriuretic peptide (ANP‐N) than age‐, sex‐ and body mass index (BMI)‐matched control subjects. Methods: Medical history, physical examination, standard 12‐lead electrocardiogram, and ANP‐N concentrations were obtained in 65 adult patients operated for ASD at the age of 21 ± 13 years (mean ± standard deviation), 21 ± 6 years after surgical closure of ASD. Sixty‐seven healthy subjects matched for age, sex and BMI served as controls. Results: In the patients serum ANP‐N was higher than in the control subjects 0.41 ± 0.32 nmol/l, median 0.31 nmol/l, interquartile range (IQR) 0.21–0.49 nmol/l vs. 0.24 ± 0.12 nmol/l, median 0.23 nmol/l, IQR 0.17–0.29 nmol/l, ( P = 0.0003). Patients with concomitant diseases had higher ANP‐N concentrations (0.51 ± 0.39 nmol/l, median 0.34, IQR 0.26–0.73 nmol/l) than ASD patients without any history or signs of disease (0.28 ± 0.16 nmol/l, median 0.27, IQR 0.17–0.40 nmol/l, P = 0.01). The ‘healthy’ ASD patients had higher hormone concentrations than age‐, sex‐ and BMI‐matched control subjects (0.28 ± 0.16 median 0.27 nmol/l, IQR 0.17–0.40 nmol/l and 0.21 ± 0.07 nmol/l, median 0.20 nmol/l, IQR 0.15–0.27 nmol/l, P = 0.01). Multiple stepwise linear regression analysis showed that age at operation was strongly associated with the post‐operative ANP‐N concentration ( r 2 = 0.25, P = 0.0002). Conclusion: ASD patients have higher ANP‐N concentrations late after surgical repair. Hormone levels correlate with age at operation. Our finding supports the clinical praxis of operating on these patients in their childhood and adolescence.