Interatrial communication

Interatrial communication, commonly known as atrial septal defect (ASD), is a congenital heart defect characterized by an abnormal opening in the septum (wall) that separates the two upper chambers (atria) of the heart. This opening allows oxygen-rich blood from the left atrium to mix with oxygen-poor blood in the right atrium, resulting in a left-to-right shunt that increases blood flow to the lungs. There are several types of ASD, including ostium secundum (the most common, located in the central portion of the septum), ostium primum (located in the lower part of the septum, often associated with atrioventricular valve abnormalities), sinus venosus (located near the entry of the superior or inferior vena cava), and coronary sinus defects. Many individuals with small ASDs are asymptomatic in childhood, and the defect may not be detected until adulthood. When symptoms do occur, they can include fatigue, shortness of breath (especially during exercise), frequent respiratory infections, heart palpitations, and poor growth in children. If left untreated, a significant ASD can lead to serious complications over time, including right heart enlargement, pulmonary hypertension, atrial arrhythmias (such as atrial fibrillation or flutter), heart failure, and in rare cases, paradoxical embolism leading to stroke. Treatment depends on the size and type of the defect and the presence of symptoms. Small ASDs may close spontaneously during childhood and require only monitoring. Larger or hemodynamically significant defects typically require closure, which can be achieved through percutaneous transcatheter device closure (for suitable secundum-type defects) or open-heart surgical repair. Early intervention generally carries an excellent prognosis. Patients with repaired ASDs usually have a normal or near-normal life expectancy, though long-term follow-up is recommended to monitor for arrhythmias or residual shunting.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Common questions about Interatrial communication