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Mitral Annular Subvalvular Aneurysm With Leaflet Perforation and Left Atrium-to-Left Ventricle Fistulous
Daniela Harsanyi1, Ana Carolina Loayza Benchimol Barbosa1, Jessica Silva Nicolau1
1Emergency Department, Instituto do Coração (InCor), Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Background:
Mitral annular subvalvular aneurysm (MASA) is a rare cardiac condition with variable etiology and potentially life-threatening complications.
Case Summary:
A 35-year-old previously healthy man of African descent presented with progressive dyspnea and weight loss. Multimodality imaging revealed a posterior MASA complicated by leaflet perforation, left atrium-to-left ventricle fistula, and severe mitral regurgitation. Despite negative microbiological and histological results, morphological and intraoperative findings strongly suggested healed infective endocarditis rather than a congenital origin. Urgent mitral valve replacement with aneurysm exclusion was successfully performed.
Discussion:
This case highlights the diagnostic and surgical value of multimodality imaging-including echocardiography, cardiac computed tomography, and magnetic resonance-in confirming MASA and supporting an acquired inflammatory etiology when infectious work-up is inconclusive.
Take-Home Messages:
MASA secondary to healed endocarditis should be suspected in the presence of leaflet perforation, atrioventricular fistula, and severe mitral regurgitation. Comprehensive multimodality imaging is essential for diagnosis and surgical planning.
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