Atrial septal defect natural history


 * Associate Editor(s)-In-Chief: Priyamvada Singh, M.B.B.S. [mailto:psingh@perfuse.org]; Assistant Editor(s)-In-Chief: Kristin Feeney, B.S. [mailto:kfeeney@perfuse.org]

Overview
The majority of atrial septal defect patients are asymptomatic until adulthood. Symptom onset and severity is largely dependent upon the size of the defect. Without intervention prior to the development of Eisenmenger's syndrome, the mortality rate for symptomatic adults is greater than 50%. Possible complications include atrial fibrillation, pulmonary hypertension and stroke.

Natural history
As many atrial septal defect patients are asymptomatic, it is common to survive into adulthood without any need for intervention. Many atrial septal defects smaller than 8 mm in diameter close spontaneously during infancy. Spontaneous closure is uncommon in children and adults. During adulthood there can be the onset of symptoms and an altered life expectancy. Beyond 40-50 years of age, survival without intervention is under 50% with a mortality rate of about 6% per year. Complications occur later in life and include atrial fibrillation, pulmonary hypertension, and stroke.

In a study involving 128 adult (age range 18 to 67 years) atrial septal defect patients, 75% were found to be symptomatic with mild to moderate non-progressive symptoms. Less than 25% of patients had significant pulmonary artery hypertension. Pulmonary artery involvement can be progressive and can lead to shunt reversal, Eisenmenger’s syndrome and ultimately death. The prognosis following medical and / or surgical treatment of pulmonary hypertension can be poor. Heart failure and atrial arrhythmias were other complications found associated with atrial septal defects, mostly in elderly patients.