An 11-month-old girl was diagnosed with pulmonary atresia with intact ventricular septum and symmetrical pectus excavatum that had developed after prior palliative operation. We performed a transannular patch repair and atrial septal defect closure. Simultaneously, to prevent postoperative right ventricular outflow tract compression, the sternum was elevated by two 1-0 braided polyester horizontal mattress sutures on the posterior side of the third and fourth costal cartilages. Postoperative respiratory distress did not occur and her hemodynamics was stable. Four months later, she is alive and well without recurrence of the thoracic deformity.