A 46-year-old man presenting with fever, peripheral edema, and chest pain was admitted to the emergency department. Electrocardiogram showed sinus tachycardia and first-degree atrioventricular block. Transesophageal echocardiogram showed infective endocarditis in bicuspid aortic valve, complicated with severe aortic regurgitation, ring abscess, and sinus-of-Valsalva aneurysm extending to mitroaortic fibrous continuity. The patient, who was unaware of his bicuspid aortic valve condition, reported having undergone an orthodontic procedure complicated with dental abscess 1 month prior, which was treated with combined clavulanate–amoxicillin antibiotic therapy. Blood cultures were positive for
Bacteroides fragilis resistant to metronidazole. Intravenous antibiotic therapy was undertaken, with rapid resolution of fever. He eventually underwent successful aortic homograft implantation and mitral valve repair with residual first-degree atrioventricular block.