Single-stage repair of congenital complete sternal agenesis with PFO-type interatrial communication and aortic arch variant complicated by an unexpected ascending aortic pseudoaneurysm: a case report

Abstract

Background: Congenital complete sternal agenesis is an exceptionally rare anterior chest wall malformation that leaves mediastinal structures without normal bony protection and may coexist with cardiovascular anomalies. Surgical management must be individualized according to age, symptoms, associated lesions, and feasibility of chest wall reconstruction. Case presentation: An 8-year-old girl weighing 20 kg with congenital complete absence of the sternum presented with cosmetic concerns only and had no cardiopulmonary symptoms. Transthoracic echocardiography demonstrated a small patent foramen ovale-type interatrial communication at the fossa ovalis with left-to-right shunting, normal cardiac chamber dimensions, and normal pulmonary artery pressure. Contrast-enhanced computed tomography of the chest confirmed complete sternal absence and demonstrated a right-sided aortic arch with a retro-esophageal left subclavian artery, without clinical evidence of tracheoesophageal compression. During single-stage operative repair, an unexpected ascending aortic pseudoaneurysm was identified above the sinuses of Valsalva, with no dissection, infection, or aortic valve abnormality. Cardiopulmonary bypass was established; the interatrial communication was closed by direct primary suturing; and the pseudoaneurysm was repaired using a biological patch sutured with polypropylene. Chest wall reconstruction was achieved by approximating the medial rib ends and costal prominences using six wire sutures without a bone graft. Case discussion: This case highlights the feasibility of combined intracardiac, aortic, and chest wall reconstruction in a stable older child and emphasizes the need for preparedness for unexpected intraoperative vascular pathology. Conclusion: A tailored single-stage repair achieved an uncomplicated early course, discharge on postoperative day 5, and normal 3-month clinical and echocardiographic follow-up.