Improvement In Left Ventricular Diameter After Closure Of Atrial Septal Defect With Fenestrated Patch: A Cross-sectional Study

Atrial septal defect (ASD) is one of the most common congenital heart diseases. It is typically characterized by a left-to-right shunt which results in volume overload of the right ventricle and overcirculation of the pulmonary vascularization (le Gloan et al., 2018). This may further result in arrhythmia, right ventricular dysfunction, and pulmonary hypertension (PH). Pulmonary hypertension is caused by endothelial dysfunction, remodelling of the pulmonary vascularization, which increases pulmonary vascular resistance, and eventually causes shunt reversal into right-to-left (Eisenmenger's syndrome). At this point, closure of the defect is contraindicated.

Small LV, although less extensively studied than dilated LV, also implies impaired LV function. Small LV means less tolerance to volume overload, which in turn impairs cardiac output and presents higher risk of heart failure and mortality (Saito et al., 2021).

ASD closure in cases with severe pulmonary hypertension (PH) presents a clinical challenge. Complete closure may cause pulmonary hypertensive crisis and low cardiac output syndrome; however, if left untreated, the disease progresses, the pulmonary vascular resistance increases, which may also lead to Eisenmenger's syndrome and shunt reversal. Today, this condition is treated with fenestrated closure, either with patch or fenestrated septal occluder. The fenestration is hypothesized to provide protective effect against pulmonary hypertensive crisis because it allows blood to flow from right to left heart. The added volume into the left heart is then, hypothesized, to provide volume training for the left heart, mainly in the case of small LV. Therefore, this study aims to evaluate the effect of fenestrated closure compared to non- fenestrated closure to the left ventricular size at systole and diastole.