American Heart Association/American College of Cardiology recommendations for imaging for infective endocarditis

Class I - There is evidence and/or general agreement that TTE or TEE should be performed in patients with native or prosthetic valve IE.
Class IIa - The weight of evidence or opinion is in favor of the usefulness of TTE or TEE in patients with native or prosthetic valve IE.
Class IIb - The weight of evidence or opinion is less well-established for the usefulness of TTE or TEE in patients with native or prosthetic valve IE.