ObjectiveTo evaluate the advantages and disadvantages of parasternal minimally incision surgery over median sternotomy to treat atrial septal defect (ASD) patients. MethodsWe retrospectively analyzed the clinical data of 55 ASD patients received ASD closure under cardiopulmonary bypass (CPB) in Department of Cardiovascular Surgery, West China Hospital from November 2010 through March 2014. There were 16 males and 39 females with an average age of 25.8 (range, 9-56 years). All the patients were divided into two groups depending on different surgical approach:a median sternotomy group (a MS group, 15 patients)and a parasternal minimally incision group (a PMI group, 40 patients). There was no statistical difference in age, gender, weight, cardiac function classification (NYHA), and atrial septal defect diameter between the two groups (P>0.05). We analyzed the clinical data of the patients and followed up for 6 months. ResultsAfter operation, no death occurred in the two groups. One patient in the MS group prolonged hospitalization due to poor postoperative heart function. One patient in the PMI group prolonged hospitalization because of pulmonary infection. Patients in the PMI group had longer operation time (P=0.007) and cardiopulmonary bypass (CPB) time (P < 0.001), higher cost in hospital (P=0.040), less intraoperative blood loss, less postoperative drainage volume on the first day (both P < 0.001). There was no statistical difference in aortic clamp time (P=0.500) mean hospital stay (P=0.290) after operation between the two groups. To eliminate the interference of the learning curve, there was no statistical difference in operation time (P=0.275) and hospitalization cost (P=0.188) between the two groups. While there was a statistical difference in CPB time between the two groups (P=0.007). There was no remnant shunts or wound complications in the two groups at the end of following up for 6 months. More patients in the PMI group could engage in non-strenuous activities with a statistical difference (P < 0.001). ConclusionParasternal minimally incision in the treatment of atrial septal defect is safe, effective, minimally invasive, with easy operation and shorter learning curve. It can be used as an important part of minimally invasive treatment procedure of congenital heart disease.