title: Cardiac septal aneurysm mimicking pseudomass: appearance on ECG-gated cardiac MRI and MDCT.
abstract: OBJECTIVE
  Cardiac septal aneurysms in adults are diagnosed when the interatrial or interventricular septal membrane deviates more than 10-15 mm to either side in the cardiac chamber. Routine non-ECG-gated chest CT does not have sufficient temporal and spatial resolution for adequate characterization of such an entity. We report the imaging findings of cardiac septal aneurysms depicted in two patients with ECG-gated cardiac MRI and in a third with ECG-gated cardiac 64-MDCT. Each aneurysm was initially believed to be a cardiac tumor on the basis of the appearance on non-ECG-gated chest CT or MRI.
  
  
  CONCLUSIONS
  Nonopacified blood can fill a cardiac septal aneurysm and mimic a pseudomass. It is important that radiologists recognize such an entity on chest CT and MRI because of the association with intracardiac shunting and stroke and to avoid misdiagnosis of an aneurysm as a cardiac tumor.
authors.affiliation: Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St., Boston, MA 02114, USA. jddodd@partners.org
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Dodd
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Aquino
authors.forename: Godtfred
authors.initials: G
authors.lastname: Holmvang
authors.forename: Ricardo C
authors.initials: RC
authors.lastname: Cury
authors.forename: Udo
authors.initials: U
authors.lastname: Hoffmann
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Brady
authors.forename: Suhny
authors.initials: S
authors.lastname: Abbara
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D004562:Electrocardiography / Q000379:methods; D006322:Heart Aneurysm / Q000175:diagnosis*; D006338:Heart Neoplasms / Q000175:diagnosis*; D006346:Heart Septum / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*