Patients with congenital atrial septal defects: Effect of age at repair and defect size on pulmonary artery pressures prior to repair

Background: Pulmonary arterial hypertension (PAH) is a major complication of atrial septal defect (ASD) and can be responsible for significant functional limitations and early mortality. Various factors have been shown to predispose ASD patients to the development of PAH. Our study aimed to determine the association between the size of the ASD, the age of the patient and the increase in pulmonary artery pressures. Methods: Data from 74 ASD patients was retrospectively reviewed, including the patients' presenting symptoms, vital parameters, comorbidities, as well as their preoperative diagnostic workup. Echocardiography findings were used to determine the type and size of the ASD, and pulmonary artery pressures were evaluated using tricuspid regurgitation velocity as assessed by echocardiography or based on cardiac catheterization data. All patients underwent ASD repair either surgically or via percutaneous repair. Univariate and multivariate linear regression was performed to analyze the effect of age and defect size on pulmonary artery pressures. Model adequacy check was also done for the final model. Postoperative morbidity/mortality was additionally evaluated. Results: The study sample comprised 44.6% males and 55.4% females. The most prominent presenting features were shortness of breath (70.3%), chest pain (43.2%), and palpitations (33.8%), and arterial hypertension was the commonest morbidity. Using multiple linear regression analysis, age and size of ASD were found to be independently associated with pulmonary artery pressure. We found that for every 1mm increase in the size of the ASD, pulmonary artery systolic pressure (PASP) increased by 0.32mmHg (p ≤ 0.05). Similarly, with every increase of one year in age, pulmonary artery pressure increased by 0.24mmHg (p0.02). No significant postoperative complications were reported following both types of repair. Conclusions: Our study concludes that ASD patients are at greater risk of developing PAH with increasing age and increasing ASD size. This can potentially help to determine which ASD patients are at greater risk and require urgent repair of their defects. The study also shows that early repair is best to prevent complications.