This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
An ostium secundum atrial septal defect is a type of congenital heart defect called an atrial septal defect (ASD). An ASD is a hole in the wall (septum) between the two upper chambers of the heart (the atria). ASDs can be classified by location. An ostium secundum ASD is a hole in the center of the atrial septum.
Normally, the right side of the heart pumps oxygen-poor blood to the lungs, while the left side pumps oxygen-rich blood to the body. An ASD allows blood from both sides to mix, causing the heart to work less efficiently.
A small hole may not cause any symptoms or problems. A larger hole can eventually cause symptoms such as shortness of breath, respiratory infections, fainting, irregular heart rhythms or fatigue after mild activity. Larger ASDs can also ultimately lead to pulmonary artery hypertension, right ventricular hypertrophy (enlargement); SVT, or heart failure.
Most cases of ASD are not inherited and occur by chance. Some cases appear to have autosomal dominant inheritance.
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