Febrile Atrioventricular Block Revealing a Trigone Abscess: A Misleading Presentation of Mitral Endocarditis

Abstract

Introduction: Infective Endocarditis (IE) is a life-threatening infection, often affecting damaged valves but occasionally occurring in patients without known cardiac history. Atypical presentations may delay diagnosis.

Observation: We present the case of a 68-year-old man with no known heart disease, admitted for respiratory symptoms. Initial work-up suggested pneumonia. Persistent fever and symptomatic bradycardia revealed a high-grade Atrioventricular Block (AVB). Echocardiography identified mitral valve vegetation. Transesophageal echocardiography confirmed an aorto-mitral trigonal abscess.

Discussion: Perivalvular abscesses, especially in the aorto-mitral region, are severe IE complications and frequently cause conduction disorders. AVB should prompt urgent evaluation with transesophageal echocardiography. Despite appropriate antibiotics and urgent surgery (mitral valve replacement, abscess drainage, pacing), the patient died from septic shock and multiorgan failure.

Conclusion: This case emphasizes the need for high suspicion of IE in atypical presentations. Early imaging, multidisciplinary management, and timely surgery are key to improving outcomes in complicated IE.