A Man in His 30s With a New Continuous Murmur and Fever

What is the cause of the continuous murmur in this patient with a fever? Fever and a new heart murmur in a young patient appropriately raise a concern of infective endocarditis. Initial diagnostic workup includes blood cultures and transthoracic echocardiography,¹ which may show a regurgitant jet across an affected heart valve. However, jet appearance and the association with patient history and physical examination findings may suggest alternative diagnoses.