Patent foramen ovale: Congenital heart defect

Patent foramen ovale (PFO) is a heart condition that causes a hole to form between the left and right atrium (upper chambers) of the heart. This hole exists in everyone before birth, but usually closes shortly after a baby is born. With patent foramen ovale, the hole does not close naturally after a baby is born. The condition almost never causes symptoms that make treatment unnecessary. Some patients who do experience symptoms or suffer from other conditions do require medication and/or surgery.

  • Causes of hole between left and right atrium
  • Risk factors of congenital heart defect
  • Symptoms
  • Diagnosis and examinations
  • Treatment of patent foramen ovale
  • Prognosis of heart disease
  • Complications


Causes of hole between left and right atrium

A foramen ovale allows blood to flow around the lungs. A baby’s lungs are not needed as the baby grows in the womb, so the hole will not cause any problems in an unborn baby. The opening normally closes shortly after birth, but in some babies this does not happen. In about one in four babies, the opening never closes. If the hole does not close, it is a patent foramen ovale. The cause of a patent foramen ovale is unknown in October 2020.

Risk factors of congenital heart defect

There are no known risk factors for congenital heart disease. Sometimes patent foramen ovale occurs in combination with other heart defects such as atrial septal aneurysms or a Chiari malformation.


Babies with a patent foramen ovale who have no other heart conditions show no symptoms. Occasionally, signs such as:

  • a blue discoloration of the skin, lips or fingers (cyanosis) which is the result of a lack of oxygen
  • cardiac arrhythmias
  • shortness of breath
  • migraine (attacks of an aura and/or one-sided headache)
  • fatigue


Diagnosis and examinations

The doctor uses electrocardiography (measurement of the heart’s electrical activity) to diagnose a patent foramen ovale. If he cannot easily see the patent foramen ovale, the cardiologist will perform a bubble test. He injects a saline solution (salt water) into the body while simultaneously performing an ultrasound of the heart (echocardiography). If the baby suffers from a patent foramen ovale, the cardiologist will see small air bubbles moving from the right side to the left side of the heart. An ultrasound of the esophagus can also be used to detect heart disease.

Treatment of patent foramen ovale

This condition does not require medical treatment unless there are other heart problems or symptoms or if the patient has had a stroke resulting from a blood clot in the brain. The treatment usually requires a cardiac catheterization in which the cardiologist permanently closes the patent foramen ovale.

Prognosis of heart disease

A baby who has no other heart defects has normal health and lifespan.


Typically, a patent foramen ovale does not cause complications unless other defects are present. Some patients suffer from shortness of breath and low arterial blood oxygen levels when sitting or standing up. This rare condition is known in medical terms as platypnea-orthodeoxia. Very rarely, patients with patent foramen ovale experience a certain type of stroke, namely a paradoxical thromboembolic stroke. In a paradoxical stroke, a blood clot that develops in a vein (often leg veins) breaks off and travels to the right side of the heart. Normally this clot travels to the lungs, but in a patient with a patent foramen ovale the clot travels through the hole to the left side of the heart. It is then pumped to the brain and becomes stuck there, restricting blood flow to that part of the brain (stroke). Some patients take medications to prevent blood clots.

read more

  • Cardiac catheterization: Procedure for examining the heart
  • Heart Health: Tips for a Healthy Heart & Heart Disease Prevention
  • Cardiac rehabilitation: Rehabilitation program after heart problems
  • Congenital heart defects (congenital heart disease) in babies
  • Congenital Defects: Causes of Birth Defects