Atrial septal defect, sometimes called ASD, is the third most common congenital heart defect, notes the Cleveland Clinic. Two types of ASD exist: patent foramen ovale, where the opening infants have at birth between the top chambers of the heart doesn't close after birth, and an abnormal additional opening between the two atria. Blood flows through the opening from the left to right atrium, causing extra blood flow through the right side of the heart. Risks of serious side effects increases with ASDs larger than 0.8 inches.
Stroke
One of the most serious potential risks of ASD is stroke. Some people have transient ischemic attacks, also known as TIAs, before they have a stroke. Stroke may also be the first sign of ASD; 40 percent of people who have a stroke with no other risk factors for stroke have a patent foramen ovale, states the Cleveland Clinic. Blood thinners to prevent clots from forming or surgery can reduce the risk of stroke in people with patent foramen ovale.
Pulmonary Hypertension
Pulmonary hypertension, elevated pressure in the arteries that lead to the lungs, can occur in people with ASD because of the increased blood flow to the lungs. Pulmonary hypertension can, in rare cases, cause permanent damage to the lungs, a condition called Eisenmenger syndrome. Eisenmenger syndrome often develops in childhood or young adulthood, and can cause heart arrhythmias, or irregular heartbeats, fainting, weakness or coughing up blood. Cyanosis, a bluish discoloration of the extremities and face that indicates lack of oxygen in the blood, also occurs as a symptom of Eisenmenger syndrome, according to MedlinePlus.
Heart Failure
The extra fluid in the right side of the heart can cause enlargement of the heart chambers. When the ventricle stretches, it pumps less effectively, which can lead to right-sided heart failure. Symptoms of ride-sided heart failure can cause fluid retention and swelling in the legs and feet, shortness of breath and fatigue. Diuretics, medications that reduce the amount of fluid in the body, and medications that regulate and strengthen the heart beat, are used to treat right-sided heart failure. Right-sided heart failure can lead to left-sided failure, which causes difficulty breathing, anxiety and a feeling of suffocation.
Shortened Life Span
People with severe atrial septal defects that haven't had the defect repaired may have a decreased life span, according to MayoClinic.com.
