RARE VARIANTS OF DIVIDED RIGHT VENTRICLE WITH SEQUESTERED APICAL TRABECULAR COMPONENT

The right ventricle may be divided into two or more compartments by va rious structures in various ways. Rarely, the apical trabecular compon ent may be sequestered from the rest of the right ventricle. We report 4 cases with different underlying lesions that share a common patholo gy of apical sequestration of the right ventricle resulting in diverse hemodynamic consequences. Case 1 had pulmonary valve stenosis. The ap ical sequestration of the right ventricle resulted in no significant h emodynamic consequence. Case 2 had multiple defects in the muscular ve ntricular septum. The volume of left-to-right shunt seemed to be reduc ed because of the commitment of some of the defects to the sequestered cavity. Case 3 had a large defect in the trabecular septum. As the de fect involved the whole septum that was related to the sequestered rig ht ventricular apex, the left ventricle together with the sequestered right ventricle formed a boot-shaped chamber. Hemodynamically, the mus cular shelf was an interventricular septum. Case 4 had a coronary arte ry fistula to an isolated cavity that occupied the apical region of th e right ventricle. The pathology was similar to the case that was repo rted as a five-chambered heart. The abnormal cavity was, in fact, the sequestered right ventricular apex. (C) 1997 Elsevier Science Ireland Ltd.