Isolated severe leftward displacement of the septum primum: Anatomic and 3D echocardiographic findings and surgical repair

Abstract

OBJECTIVES: Leftward displacement of the septum primum is usually described as associated with hypoplastic left heart syndrome or visceral heterotaxy. This rare malformation results in partially or totally anomalous pulmonary venous drainage with a normal connection of the pulmonary veins to the left atrium, depending on the degree of septal shift. We report the 3D echocardiographic and anatomic findings as well as the surgical repair in a series of isolated severe leftward displacement of the septum primum, responsible for totally anomalous pulmonary venous drainage. METHODS: Three patients presenting with situs solitus and extreme leftward displacement of the septum primum were included. All of the pulmonary veins drained anomalously into the anatomical right atrium, and the distance between the mitral valve and the abnormal septum primum was greatly reduced, compromising the size of the left atrial chamber, but with normal left ventricle diameters. Preoperative 3D echocardiographic findings are reported. We achieved a biventricular surgical repair in all cases. The atrial septation was accomplished using an autologous pericardial patch after removing the abnormal septal membrane. RESULTS: The postoperative course was free from any cardiovascular complications. Echocardiographic scans showed a harmonious reconstruction without pulmonary venous obstructions or stenosis. CONCLUSIONS: This article reports the severe leftward displacement of the septum primum presented as an isolated cardiac malformation; 3D transthoracic echocardiography allowed an accurate diagnosis of this malformation and helped in choosing the best surgical strategy.