PRIMARY ATRIAL SEPTAL ANEURYSM an‎d ITS ASSOCIATED CARDIAC ABNORMALITIES: A TRANSESOPHAGEAL ECHOCARDIOGRAPHIC STUDY

Background: Primary atrial septal aneurysm (ASA) is a congenital malformation of the atrial septum which is characterized by its bulging into either atrium. Transesophageal echocardiography (TEE) has recently made it possible to detect ASA more easily and has clarified some of the previously obscure points regarding this infrequent entity. Objective: Our aim is to report the prevalence of ASA among 270 patients undergoing TEE in this center and to assess their clinical findings and associated cardiac disorders. Design: Cross sectional study. Setting: University Hospital. Methods: Over a 2-year period, 270 cases had TEE, of whom, 16 cases were diagnosed as having primary ASA. A protrusion of atrial septum ³10 mm beyond the plain of atrial septum and a base diameter of ³ 15 mm were considered diagnostic for ASA. Results: There were 8 female and 8 male patients with an age range of 19-67 years. The maximal protrusion of ASA ranged from 11-22 mm and the maximal base diameter ranged from 17-25 mm. Oscillating ASAs were present in only 3 cases and in the remaining it was bulging only toward the right atrium. Systolic click was detected in 10 cases, of whom 2 had double clicks. Two patients had documented embolic stroke by history and physical examination and brain CT scan. The most common transesophageal echocardiographic findings included ASD (26%), PFO (26%) and MVP (20%). Of interest was the presence of ostium primum defect in one of our ASD cases. Mild mitral regurgitation and AR were each detected in one case too. Three cases (20%) had no associated cardiac lesions. Conclusion: Primary ASAs are rare, however once present, they are frequently associated with ASD and PFO. In addition they may not only simulate MVP due to their ausculatatory findings but may actually be associated with it. They should be considered as a potential source for embolic stroke as well.