Left ventricular false-pseudo and pseudo aneurysm: serial observations by cardiac magnetic resonance imaging

A case of extensive inferior myocardial infarction complicated by a large ventricular aneurysm is presented. Magnetic resonance (MR) imaging 4 days after the onset showed a small protrusion from the necrotic inferior myocardium, which expanded 10 days after onset with a marked pericardial effusion. The follow-up examination by MR and CT imaging 6 months after the onset revealed a large ventricular aneurysm from the inferior cardiac wall. After the aneurysmectomy, the histological study revealed that the aneurysm wall was made up of 2 different types of walls; the peripheral part was a false-pseudo aneurysm and the central part was a pseudo aneurysm. From the serial MR imaging, it is considered that such an aneurysm is primarily formed from a small discontinuation of the LV wall followed by oozing type rupture. Finally, the ruptured central part of the LV wall, which was covered by the pericardium, formed a pseudo aneurysm and the stretched peripheral area, which contains myocardium, formed a false-pseudo aneurysm afterward and then they extended together. Thus, MR imaging provided the important information for the understanding of the formation process of the pseudo and false pseudo LV aneurysm.