Patent foramen ovale

Patent foramen ovale (PFO) is a medical condition characterized by the persistence of a small opening between the atria of the heart that normally closes shortly after birth. This opening, known as the foramen ovale, is a necessary part of fetal circulation but typically seals off as part of the normal changes that occur in the heart after birth.

Anatomy and Physiology

The foramen ovale is an opening in the septum between the right atrium and the left atrium of the fetal heart. During fetal development, this opening allows blood to bypass the non-functioning fetal lungs and flow directly from the right atrium to the left atrium, facilitating efficient oxygenation via the placenta. After birth, the increase in blood pressure in the left atrium typically causes the foramen ovale to close, forming a structure known as the fossa ovalis.

Pathophysiology

In some individuals, the foramen ovale fails to close completely, resulting in a patent foramen ovale. This condition can allow blood to flow between the atria, potentially leading to various complications. While many people with a PFO are asymptomatic, the condition can be associated with an increased risk of stroke, particularly in the presence of other risk factors such as deep vein thrombosis (DVT) and pulmonary embolism.

Diagnosis

PFO is often diagnosed incidentally during echocardiography performed for other reasons. Specific diagnostic techniques include:

• Transthoracic echocardiography (TTE)
• Transesophageal echocardiography (TEE)
• Bubble study during echocardiography

Treatment

Treatment options for PFO depend on the presence and severity of symptoms. Asymptomatic individuals typically do not require treatment. For those with symptoms or complications, options may include:

• Antiplatelet therapy
• Anticoagulation therapy
• Percutaneous closure using a catheter-based device
• Surgical closure

Prognosis

The prognosis for individuals with a PFO is generally good, especially if the condition is asymptomatic. However, those with a history of stroke or other complications may require ongoing medical management to reduce the risk of future events.

Related Pages

• Atrial septal defect
• Echocardiography
• Stroke
• Deep vein thrombosis
• Pulmonary embolism