The cost of surgery for a cardiac atrial septal defect is around $20,000 to $50,000. If surgical open-heart treatment is required, it may be $20,000 to $30,000, and medical intervention may be $40,000 to $50,000. Depending on the treatment and the materials needed, the specific costs may vary. Atrial septal defect is mainly surgical repair, and the prognosis is generally very good, with an average natural life expectancy of 50 years, with some surviving 70 years. If the defect is large, pulmonary hypertension and heart failure are likely to occur and the prognosis is poor. The prognosis for defects without closure of the first foramen is also poor, and some may develop arrhythmias, most commonly atrial fibrillation, within 10-20 years after surgery.