A 37-year-old man presenting with fever and chest pain was admitted to our hospital. Electrocardiogram showed sinus tachycardia and complete left bundle branch block. Transthoracic echocardiogram showed infective endocarditis in the bicuspid aortic valve, complicated by multiple hyperechoic vegetations and severe aortic regurgitation. Blood cultures were negative and intravenous empiric antibiotic therapy was begun. However, fever lasted for 7 days and follow-up echocardiography revealed a newly emerged perivalvular abscess. The patient eventually underwent an urgent aortic root replacement that confirmed the echocardiographic findings. Our case report emphasizes that all patients with suspected aortic valve endocarditis should undergo early and follow-up echocardiographic studies.