Atrial Septic Defect (ASD) and Patent Foramen Ovale (PFO)

Atrial septal defect (ASD), sometimes referred to as a hole in the heart, is a form of congenital heart defect in which there is an abnormal opening in the dividing wall between the upper filling chambers of the heart (the atria). This enables blood flow between the upper chambers of the heart which can lead to a build-up of blood pressure in the lungs and less oxygen in the blood that goes to the body. Patent foramen ovale (PFO) is one type of atrial septal defect. It is a hole in the heart that didn't close the way it should after birth that results in the creation of a flap or a valve-like opening in the atrial septal wall.


The size of an ASD and its location in the heart will determine what kinds of symptoms are experienced. Most people with ASDs seem healthy and appear to have no symptoms. However, those with larger, more severe ASDs, might have some of these signs or symptoms:
  • poor appetite
  • poor growth
  • fatigue
  • shortness of breath
  • lung problems and infections, such as pneumonia


If an ASD is suspected, the cardiologist might order one or more tests such as a chest X-ray, electrocardiogram (EKG) or echocardiogram (echo) to produce images and measure the electrical activity of the heart.


If an ASD is not treated, health complications can develop later, including an abnormal heart rhythm (atrial arrhythmia) and problems with how well the heart pumps blood. There might also be at an increased risk for stroke, since a blood clot that develops can pass through the hole in the wall between the atria and travel to the brain. Pulmonary hypertension (high blood pressure in the lungs) also can develop over time in older patients with larger untreated ASDs.   Currently, there are two main treatment methods for PFO: medicines or PFO closure, which can include open-heart surgery or a newer procedure that closes the flap without major surgery. This opening can allow a blood clot from one part of the body to travel through the flap and up to the brain, causing a stroke.