An interventricular membranous septal aneurysm obstructing the right ventricle outflow tract in a five-year-old boy: a case report

BACKGROUND: While the aneurysms of the membranous septum (AVS) are rare, the possibility that they lead to obstruction is even rarer. To the best of our knowledge, 11 similar cases have been reported since 1982. CASE PRESENTATION: Initially, the five-year-old boy was evaluated for dyspnoea that had been present since birth. He did not receive any medical treatment until the previous year. At the age of four, the transthoracic echocardiography showed a large aneurysm extending to the right ventricular outflow tract (RVOT) and causing RVOT stenosis. Complete surgical resection of the aneurysmal tissue was performed, and the boy was discharged home in satisfactory condition. CONCLUSIONS: As the occurrence of RVOT obstruction by a membranous ventricular septal aneurysm is very rare, we are reporting the second case in which an aneurysm of the membranous septum dynamically obstructed the RVOT in a child. We are also reviewing all the previously reported similar cases in the literature. Further studies are needed to obtain a more comprehensive understanding of aneurysms of the membranous septum (AVS).