Patent Foramen Ovale Detection and Management

Introduction to PFO Detection

The American Heart Association recommends screening for PFO with echocardiography with agitated saline bubble study for risk stratification in patients with pulmonary embolism 1
The American Heart Association recommends Transcranial Doppler (TCD) with bubble study and Valsalva maneuver for initial screening of PFO in patients with suspected paradoxical embolism 2, 3

The presence of a PFO in patients with pulmonary embolism increases the risk of death (relative risk 2.4), ischemic stroke (relative risk 5.9), and peripheral arterial embolism (relative risk 15) 1
In patients with pulmonary embolism, PFO presence is associated with a significantly increased risk of silent brain infarcts (33% vs. 2% in those without PFO) 1
PFO is found in 39.2% of cryptogenic stroke patients versus 29.9% of patients with known stroke causes (p<0.02), with a stronger association in younger patients (<55 years) 2
The association between PFO and cryptogenic stroke is more convincing in patients with atrial septal aneurysm or elevated right atrial pressure 2, 4

Transthoracic Echocardiography (TTE) with bubble study and Valsalva maneuver is useful for initial detection of PFO in patients with cryptogenic stroke or other embolic events 2
Transesophageal Echocardiography (TEE) with bubble study is the gold standard for confirming PFO and right-to-left shunting, providing detailed visualization of atrial septal anatomy, and is essential when PFO closure is being considered 5, 6, 1
Cardiac MRI can be used for planning transcatheter PFO closure procedures, as recommended by the American College of Cardiology, and for detailed visualization of atrial septal anatomy before PFO closure 5, 7
Cardiac MRI is inferior to TEE for detection of contrast-enhanced right-to-left shunting and has limited sensitivity for detecting mild shunts, with only 18.8% of mild shunts detected by TEE identified by MRI 5
The American College of Cardiology recommends cardiac MRI for quantification of right-to-left shunting and detection of associated atrial septal aneurysm, which increases embolic risk 5

The American Heart Association recommends considering PFO closure in patients with recurrent cryptogenic stroke despite medical therapy, large PFO with significant right-to-left shunting, or coexisting atrial septal aneurysm 2, 8
PFO closure may be considered, particularly in patients ≤60 years with high Risk of Paradoxical Embolism (RoPE) scores (>6), and the presence of atrial septal aneurysm increases embolic risk 6
Antiplatelet therapy is standard for most cryptogenic strokes, and anticoagulation may be considered with concurrent venous thromboembolism 6
A combined approach using transcranial Doppler bubble test plus carotid ultrasound can help determine which patients truly need TEE, with a 97.1% negative predictive value for therapy-relevant TEE findings 6
Brain MRI can be used to detect silent cerebral ischemic lesions before and after PFO closure, as recommended by the American College of Cardiology, and to monitor for new silent lesions after PFO closure 5, 1