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Otto et al 2020 ACC/AHA Guideline for the Management of Valvular Heart Disease

Circulation. 2021;143:e72–e227. DOI: 10.1161/CIR.0000000000000923 February 2, 2021 e151 CLINICAL STATEMENTS AND GUIDELINES

11.8 Prosthetic Valve Stenosis

11.8.1 Diagnosis of Prosthetic Valve Stenosis

Recommendations for Diagnosis of Prosthetic Valve Stenosis Referenced studies that support the recommendations are summarized in Online Data Supplement 40. COR LOE Recommendations

1 B-NR 1.  In patients with suspected mechanical or bioprosthetic valve stenosis, TTE and TEE are recommended to diagnosis the cause and severity of valve obstruction, assess ventricular function, and estimate pulmonary artery systolic pressure.1,2

1 C-EO 2.  In patients with mechanical valve stenosis, fluoroscopy or cine-CT is recommended to assess motion of the mechanical valve leaflets.

2a C-LD 3.  In patients with bioprosthetic valve stenosis, 3D TEE or 4D CT imaging can be useful to rule out leaflet thrombosis.3–7

Synopsis

Prosthetic valve stenosis can occur with both mechanical and bioprosthetic valves. Echocardiographic definitions of stenosis severity have been provided by the American Society of Echocardiography.1 Obstruction of a mechanical valve may be caused by thrombus formation that leads to abnormal leaflet mobility, pannus ingrowth, or a combination of the two.8 Bioprosthetic valve stenosis may be caused by structural valve deterioration, with leaflet degeneration by thickening, calcification, or tear as the end stage of a slowly progressive process resulting in abnormal leaflet motion, or it may be attributable to other structural causes, including stent creep. Bioprosthetic valve stenosis may also be attributable to nonstructural causes, such as endocarditis, leaflet thrombus, or pannus. The progressive stages are defined by the Valve Academic Research Consortium criteria.9

Recommendation-Specific Supportive Text

1.	 TTE and TEE assessment can appropriately detect and quantify prosthetic valve stenosis.1 TTE within 3 months after valve implantation is useful to provide baseline data on valve hemodynamics and ventricular function. In some patients, the orifice area of the implanted prosthesis may be inadequate to meet the cardiac output demands of the patient, even when the prosthetic valve itself is functioning normally. This circumstance, termed patient–prosthesis mismatch, is associated with a high transvalvular gradient, persistent LV hypertrophy, and an increased rate of cardiac events after valve replacement.10,11 Diagnosis in the setting of bileaflet mechanical valves is complicated by nonlaminar patterns of blood flow, for which significant pressure recovery may be present; thus, a high velocity in the central narrow slit-like orifice may not correlate with prosthetic valve stenosis or patient– prosthesis mismatch. Prosthetic valve stenosis is distinguished from patient–prosthesis mismatch by comparison with the early postoperative baseline study and by visualization of the appearance and motion of the valve leaflets. Prosthetic valve stenosis is characterized by a clinical course of progressive increase in transvalvular velocity and pressure gradient in conjunction with abnormal thickened/calcified leaflets (for bioprosthetic valves) or evidence of pannus formation (with mechanical valves). 2.	 The motion of the leaflets of a mechanical valve is best evaluated radiographically with fluoroscopy or cine-CT imaging because strong reflections from the mechanical valve obscure motion on echocardiographic imaging in most patients, particularly as assessed on images from the transthoracic approach. With fluoroscopic imaging, the angle of imaging must be adjusted to demonstrate leaflet motion from a side view, permitting measurement of the angles of opening and closure that can be compared with expected values for that valve type. Cine-CT images are obtained at a high frame rate focused on the prosthetic valve in a 3D acquisition. Compared with fluoroscopy, cine-CT 3D images are less operator dependent for measuring opening and closing angles. In addition, cine-CT allows detection of pannus or thrombus on or adjacent

Table 23.  Systemic Fibrinolysis Versus Surgery for Prosthetic Valve Thrombosis

Favor Surgery Favor Fibrinolysis Readily available surgical expertise No surgical expertise available Low surgical risk High surgical risk Contraindication to fibrinolysis No contraindication to fibrinolysis Recurrent valve thrombosis First-time episode of valve thrombosis NYHA class IV NYHA class I, II, or III Large clot (>0.8 cm2) Small clot (≤0.8 cm2) LA thrombus No LA thrombus Concomitant CAD in need of revascularization No or mild CAD Other valve disease No other valve disease Possible pannus Thrombus visualized Patient choice Patient choice CAD indicates coronary artery disease; and NYHA, New York Heart Association.

Adapted from several references.2,5,7,13,14 Downloaded from http://ahajournals.org by on October 7, 2026