Patent foramen ovales (PFO) and atrial septal defects (ASD) are typically diagnosed by an ultrasound of the heart, or echocardiography. Echocardiography allows for the visualization of the hole, determination of the direction of the shunt and estimation of the amount of shunt.
Other imaging tests such as a transesophageal echo (TEE), cardiac CT, and cardiac MRI (CMR) are utilized if an echo is inconclusive or if supportive information is required.
Cardiac catheterization (and to a lesser extent, CMR) are performed to give a more accurate estimation of the degree of shunt when the decision to treat is unclear.
