of the right side of the heart will lead to a reversal of this shunt. This reversal is called Eisenmenger syndrome.

Lipomatous atrial septal hypertrophy (LASH) is the fat deposition in the infoldings of the interatrial septum adjacent to the true atrial septum. It is shaped like a "dumbbell" because the deposition is located at the above and the below the fossa ovalis, sparing the fossa itself. The incidence of LASH increases with older age and obesity. On CT scan, it shows homogeneous, dumbbell