A case of a giant left ventricular pseudoaneurysm

Abstract

Cardiac pseudoaneurysm is a rare but potentially lethal complication of myocardial infarction. Clinical manifestations may be nonspecific or, in some cases, may even be silent. Therefore, high clinical suspicion should be maintained when a patient becomes unstable after a myocardial event. Efficient use of imaging examinations is crucial in providing an accurate diagnosis and, thereafter, timely and appropriate treatment. The authors report a case involving a giant left ventricular pseudoaneurysm that required both transthoracic echocardiography and magnetic resonance imaging to reach the correct diagnosis. The pathology, clinical presentation, diagnostic work-up and treatments of cardiac pseudoaneurysms are reviewed. CASe PReSenTATionA 74-year-old man was brought to the emergency department at the authors' institution for severe chest pain that began 30 min before his arrival. His work-up suggested an acute myocardial infarction (MI) of the inferior territory. Cardiac catheterization demonstrated an occlusion of the middle segment of the right coronary artery, which was successfully dilated without any immediate complications. Four hours later, the patient became unstable and complained of pleuritic chest pain. On transthoracic echocardiography (TTE), the right ventricle was not clearly identified. A large, heterogeneous and polylobulated mass measuring 7 cm × 13 cm was noted on the right side of the heart ( Figure 1A). It was not possible at the time to determine whether the mass was intraventricular or extrapericardial. With contrast injection, there was heterogeneous enhancement of the mass ( Figure 1B).Several hours later, cardiac magnetic resonance imaging (MRI) demonstrated a large pseudoaneurysm on the posteroinferior segment of the heart measuring 7.0 cm × 11.4 cm × 6.0 cm. A narrow collar measuring 8 mm was identified on the inferolateral portion of the left midventricle. Approximately 50% of the pseudoaneurysm was thrombosed, with the circulating portion measuring 4.3 cm × 7.2 cm × 2.2 cm (Figure 2). There was a transmural late gadolinium enhancement near the neck of the pseudoaneurysm, confirming infarction. The right ventricle and the inferoanterior portion of the right atrium were partially compressed. A left ventricle pseudoaneurysm was diagnosed.After discussing the situation with the patient and considering his multiple morbidities, surgical intervention was withheld. The patient was pronounced dead <48 h later. On autopsy, a rupture point was identified on the inferolateral wall of the left ventricle ( Figure 3). As observed on imaging, the posterior pericardium wall was under tension by a complex fresh thrombus estimated to weigh approximately 250 g. It was also confirmed that the pseudoaneurysm partially compressed the right heart chambers. DiSCuSSionCardiac pseudoaneurysms occur when there is rupture of the free wall of the left ventricle. Extraventricular blood is then contained by adherent pericardium or scar tissue. Unlike true aneurysms, both the cAse reportThis open-access article is d...