Patent Foramen Ovale Differential Diagnoses

Updated: Dec 17, 2017
  • Author: Sandy N Shah, DO, MBA, FACC, FACP, FACOI; Chief Editor: Yasmine S Ali, MD, MSCI, FACC, FACP  more...
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Diagnostic Considerations

Other considerations in patient with suspected patent foramen ovale (PFO) include the following:

  • Cardiac surgery

  • Hypoxemia increases in PFO due to transient elevation of right atrial pressure with an increase in right-to-left shunt resulting in systemic arterial desaturation.

  • In off-pump coronary artery bypass surgery, PFO increases the risk of postoperative atrial fibrillation and hypoxemia.

PFO is often associated with other cardiac anomalies, such as the following:

  • Atrial septal aneurysm: A redundant and mobile interatrial tissue in fossa ovalis that has phasic excursion of 10-15 mm during cardiorespiratory cycle.

  • Eustachian valve: Eustachian valve is located at junction of inferior vena cava and right atrium.

  • Chiari network: A fenestrated mobile structure consists of a network of threads and fibers in the right atrium that originate from the region of the Eustachian and thebesian valve at the orifice of inferior vena cava with attachments to upper wall of right atrium or atrial septum.

  • In a study by Schneider, 1436 consecutive patients were referred for TEE. A Chiari network was found in 29 subjects (2%), 24 (83%) had PFO, and 7 (24%) had an atrial septal aneurysm. [12]

  • Atrial septal defect: In a study of 103 patients by Khositseth who were referred for transcatheter closure for a paradoxical embolism, PFO was present in 81 subjects , ASD in 12 subjects, and both PFO and ASD in 10 subjects. [13]

  • Ebstein anomaly: In a study by Attenhofer of 106 patients, 79% had either persistent or previously closed PFO or atrial septal defect. [14]