Arch Clin Med Case Rep 2022; 6 (3): 370-373 DOI: 10.26502/acmcr.96550486 Archives of Clinical and Medical Case Reports 370 Case Report Atypical Presentation of a Large Aortopulmonary Window in a Very Low Weight and Preterm Born Infant Katja Schumacher, Sabine Meier, Michael A Borger, Martin Kostelka, Marcel Vollroth Department of Cardiac Surgery, Heart Center, HELIOS Clinic, University Hospital Leipzig, Leipzig, Germany * Corresponding Author: Marcel Vollroth, Department of Cardiac Surgery, Heart Center, HELIOS Clinic, University Hospital Leipzig, Leipzig, Germany. Received: 21 March 2022; Accepted: 05 April 2022; Published: 13 May 2022 Citation: Katja Schumacher, Sabine Meier, Michael A Borger, Martin Kostelka, Marcel Vollroth. Atypical Presentation of a Large Aortopulmonary Window in a Very Low Weight and Preterm Born Infant. Archives of Clinical and Medical Case Reports 6 (2022): 370-373. Abstract Background Aortopulmonary window represents 0.2-0.3% of all congenital cardiac malformations. Usually, aortopulmonary window results in left-to-right shunt. Thus, progressive pulmonary hypertension and its consequences are associated with this anomaly. Commonly, it is located in the ascending aorta. Case Presentation We are describing a premature low-birth-weight infant who was diagnosed with large aortopulmonary window between the pulmonary artery bifurcation and the ascending aorta extending to the aortic arch. Surgery was successfully performed at the age of 4 weeks due to progressive congestive heart failure. Conclusion This report highlights the importance of early surgical repair in patients with complex aortopulmonary window configuration. 1. Introduction With a prevalence of only 0.2-0.3% of all congenital cardiac malformations, aortopulmonary window is a rare