COR LOE Recommendations In patients with suspected mechanical or bioprosthetic valve regurgitation, TTE and TEE are recommended to determine the cause and severity of the leak, assess ventricular function, and estimate pulmonary artery systolic pressure.1 4 In patients undergoing a transcatheter procedure for paravalvular prosthetic regurgitation, 3D TEE is recommended for Synopsis The clinical presentation of prosthetic valve regur- gitation varies depending on its severity, hemody- namic effects, and etiology. In asymptomatic pa- tients, prosthetic valve regurgitation may be found incidentally on routine clinical or imaging follow-up. A change in auscultatory findings (eg, change in prosthetic valve sounds or a new murmur) should prompt suspicion of prosthetic valve dysfunction. Symptomatic patients with prosthetic valve regurgi- tation present with unexplained or new-onset HF or significant hemolysis with or without anemia. TTE is inadequate for evaluation of prosthetic mitral valves; TEE is needed when prosthetic MR is a concern. A critical step in evaluation of the patient with pros- thetic valve regurgitation is to distinguish transval- vular from paravalvular leak, which also requires TEE in addition to TTE. Figure 14. Management of prosthetic valve stenosis and regurgitation. Colors correspond to Table 2. 3D indicates 3-dimensional; 4D, 4-dimensional; CT, computed tomography; CVC, Comprehensive Valve Center; HF, heart failure; TEE, transesophageal echocardiography; TTE, transthoracic echocardiography/echocardiogram; and ViV, valve-in-valve. *See Figure 13 if valve thrombosis is suspected. CLINICAL STATEMENTS AND GUIDELINES Recommendation-Specific Supportive Text 1. Echocardiography is the primary imaging modality to assess the location and quantify the severity of pros- thetic valve regurgitation, often requiring both TTE and TEE approaches.1,3 Although TTE provides supe- rior assessment of transvalvular gradients, chamber sizes, and function, TEE is better suited to identify the cause and location of regurgitation and is essential for prosthetic mitral valve because of acoustic shadow- ing on TTE. 