Huge Pseudoaneurysm After Mitral Valve Replacement

Abstract

A 57 year-old man with a history of mitral valve replacement 12 years before was admitted for prolonged palpitations and congestive heart failure. Electrocardiogram showed sustained ventricular tachycardia. After cardioversion, despite the poor acoustic window, echocardiography showed a huge left paraventricular chamber (6 cm length) with a large neck (5 cm width), involving the basal segments of the lateral, posterior and inferior walls, associated with mitral prosthesis rocking (Fig. 1 and Video I). Left ventricle (LV) function was severely depressed. Cardiac magnetic resonance confirmed the presence of a multilobar pseudoaneurysm (8 cm × 6 cm) with a wide neck (6.5 cm), involving the basal inferior and inferolateral segments, with pericardial late enhancement (Fig. 2). Lateral insertion of the mitral prosthesis was supported only by the false aneurysm (Video II). Cardiac computed tomography showed diffuse parietal calcifications in the pseudoaneurysm as well as a large mural thrombus (Fig. 2). The patient was proposed for heart transplantation which occurred a few months later (Fig. 2). Histological analysis of the explanted heart confirmed the diagnosis by revealing the absence of myocardial cells in the wall of the chamber. Figure 2(A) Magnetic resonance (MR) 4 chamber view showing the relation of the pseudoaneurysm with the left ventricle and the mitral valve, as well as the sharp interruption of the myocardial wall characteristic of pseudoaneurysm; (B) MR short axis view once again showing the relative position of the cavity to the left ventricle and the apparent absence of myocardial wall; (C) MR 2 chamber view revealing late gadolinium enhancement in the pericardium (arrows); (D) computed tomography (CT) image showing the calcifications in the wall of the pseudoaneurysms, suggestive of chronicity; (E) CT image showing the presence of a thrombus inside the pseudoaneurysm (*) as well as the diffuse mural calcification (arrows), both findings compatible with long term evolution; (F) explanted heart, where the real dimensions of the pseudoaneurysm can be apreciated. View Large Image Figure Viewer Download Hi-res image