[Lipomatous hypertrophy of the interatrial septum: its assessment with TEE, CT and MRI]

Lipomatous atrial septal hypertrophy (LHS) is an uncommon condition characterized by the deposition of excessive adipose tissue in the atrial septum. The fossa ovalis is spared by this infiltration of fat. A variety of atrial arrhythmia has been associated with this lesion, which is more common in obese, elderly female patients. Because of the lack of specific symptoms, LHS is the outcome of casual observation during echo-Doppler or autopsy studies.

We describe the case of a 76-year-old woman who came under our observation due to stroke and atrial arrhythmia. Transesophageal echocardiography clearly revealed lipomatous atrial septal hypertrophy.

The MRI confirmed the diagnosis, visualizing the typical "dumbbell" interatrial septum. Computed tomography made it possible to define the anatomic substance of the lesion as "fatty".

Transesophageal echocardiography is the method of choice in the diagnosis of LHS. Other techniques such as RMI or CT-scan can be useful only in selected patients with large fatty infiltration of the atrial wall or marked hypertrophy of the interatrial septum.