An evaluation of atrial septal defect begins with a medical history and physical examination.

Physical findings in those with atrial septal defect may include:

• Examination of the heart may reveal a heart murmur

Tests are required to make the diagnosis of atrial septal defect, and to determine its severity.

Tests that may be used to evaluate an atrial septal defect include:

• Pulse oximetry
• Blood electrolytes
• Coagulation profile
• Chest x-ray
• Echocardiogram:
• Color-flow Doppler studies of the heart can be used in lieu of cardiac catheterization to diagnose this condition
• Electrocardiogram (EKG or ECG)
• Cardiac catheterization
• MRI scan of the chest
• MRI scan of the heart: