Pseudoaneurysm formation in infective endocarditis.

Left ventricular pseudoaneurysms that develop in the setting of infective endocarditis are believed to result from remodeling of extravalvular abscesses. The high pressure generated by the left ventricle is thought to dissect into the abscess causing it to form a characteristic sac-like protuberance readily recognized echocardiographically. Left ventricular pseudoaneurysms most often arise from abscesses in the mitral-aortic intervalvular fibrosa and protrude external to the aorta. Less often, as described herein, they arise from abscesses external the posterior mitral annulus and project into the posterior interventricular groove. Perforation may result in camo-cameral or aorto-cameral fistula formation, as well as fistulous communication with the pericardial space.