Anomalous origin of the right pulmonary artery from the ascending aorta: a case report and review of the literature.

Introduction: Anomalous aortic origin of a pulmonary artery (AORPA), or hemitruncus arteriosus, is a rare congenital anomaly in which one pulmonary artery arises directly from the ascending aorta. Without timely repair, exposure to systemic pressure leads to irreversible pulmonary vascular disease and high early mortality. Case presentation: A 4-month-old female infant presented with failure to thrive, tachypnea, and feeding difficulties. Transthoracic echocardiography and CT angiography confirmed an anomalous right pulmonary artery (RPA) originating from the posterior ascending aorta at the sinotubular junction, with a coexisting patent ductus arteriosus (PDA) and elevated right ventricular pressure. Z-scores for the RPA were not calculated because the vessel was already dilated under systemic pressure. She underwent successful direct end-to-side reimplantation of the RPA into the main pulmonary artery, with ligation of the PDA. The postoperative course was uneventful, and she was discharged on day 5 with improved symptoms. Clinical Discussion: Early surgical correction is critical to prevent pulmonary hypertension and right ventricular overload. Direct tension-free reimplantation is the preferred technique, allowing physiological repair without conduits or patches. Intraoperative assessment confirmed anastomotic patency without residual gradient. Follow-up at 30 days demonstrated a widely patent anastomosis, normalized right ventricular pressure, and satisfactory clinical progress. Structured surveillance is recommended to monitor for restenosis or asymmetric pulmonary artery growth. Conclusion: Prompt diagnosis and surgical repair of AORPA can restore normal pulmonary circulation and prevent irreversible vascular changes. Even in resource-limited settings, careful imaging and meticulous surgical technique yield excellent early outcomes. Long-term follow-up remains essential.