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Otto et al 2020 ACC/AHA Guideline for the Management of Valvular Heart Disease February 2, 2021 Circulation. 2021;143:e72–e227. DOI: 10.1161/CIR.0000000000000923 e120 CLINICAL STATEMENTS AND GUIDELINES less common causes of chronic primary MR include IE, connective tissue disorders, rheumatic heart disease, cleft mitral valve, and radiation heart disease. If volume overload of chronic primary MR is prolonged and severe, it causes myocardial damage, HF, and eventual death. Correction of the MR before irreversible changes occur can be curative. 7.2.2. Diagnosis and Follow-Up of Chronic Primary MR 7.2.2.1. Diagnostic Testing: Initial Diagnosis Recommendations for Diagnostic Testing: Initial Diagnosis of Chronic MR Referenced studies that support the recommendations are summarized in Online Data Supplement 25. COR LOE Recommendations 1 B-NR 1. In patients with known or suspected primary MR, TTE is indicated for baseline evaluation of LV size and function, RV function, LA size, pulmonary artery pressure, and the mechanism and severity of primary MR (Stages A to D).1–5 1 C-EO 2. In patients with primary MR, when TTE provides insufficient or discordant information, TEE is indicated for evaluation of the severity of MR, mechanism of MR, and status of LV function (Stages B to D). 1 B-NR 3. In patients with primary MR, CMR is indicated to assess LV and RV volumes and function and may help with assessing MR severity when there is a discrepancy between the findings on clinical assessment and echocardiography.6–9 1 B-NR 4. In patients with severe primary MR undergoing mitral intervention, intraoperative TEE is indicated to establish the anatomic basis for primary MR (Stages C and D) and to guide repair.10,11 Synopsis TTE is the initial imaging modality for patients with primary MR to look at valve morphology, severity of the MR, and the status of the LV, with TEE, CMR, or cardiac catheterization performed when insufficient or discordant information is obtained from the TTE. A TEE should be used to guide mitral valve interventions. Recommendation-Specific Supportive Text 1. TTE images provide the diagnostic data needed for clinical decision-making in chronic primary MR.1–5,12 The outcome of the patient with chronic primary MR is determined by lesion severity,5 symptomatic status.13–15 the presence of LV dysfunction, and whether valve pathology is correctable by valve repair, which is superior to valve replacement when repair is possible. Usually only severe (not mild or moderate) MR leads to negative sequelae.5,6 Favorable loading conditions in MR increase LVEF but do not affect the extent of shortening. Thus, a “normal” LVEF in MR is approximately 70%. The onset of LV dysfunction is inferred when LVEF declines toward 60% or when the LV is unable to contract to a diameter <40 mm at end systole.16–18 Although chamber volumes may give more information about cardiac remodeling,19 2D volume accuracy is variable in clinical practice. Determination of MR severity is made by integrating all available data. These data include measurements of the effective orifice area, regurgitant volume, regurgitant fraction (obtained by using the proximal isovelocity surface area or quantitative Doppler flow measurements),1–3,5,20 color jet area, vena contracta, continuous-wave Doppler intensity, and the transmitral jet velocity curve. In mitral valve prolapse, MR may be non-holosystolic (mid-late systole). Thus, careful attention in assessing its severity is needed as conventional color Doppler parameter may overestimate its severity on a single image frame. Volumetric measurements provide a better assessment in this situation.9 2. TEE provides excellent imaging of the mitral valve and should be performed when TTE images are inadequate to fulfill the goals of TTE noted previously. TEE is especially useful in cases of MR attributable to IE because TEE can provide information about other potentially infected structures. TEE may allow more precise quantitation of regurgitant severity and provide a better estimate of the likelihood of a successful surgical valve repair than does TTE. Three-dimensional TEE may be helpful in further visualizing the abnormal mitral valve anatomy, offering a “surgical” view of the valve. Mitral valve repair is preferable to valve replacement because of a lower operative mortality rate and avoidance of the complications inherent to prosthetic valves. Although the final decision about repair versus replacement is made in the operating room, TEE can help predict surgical strategy beforehand. Thus, if repair is likely, it might be performed earlier in the course of the disease than if replacement is necessary. 3. In most cases, TTE provides the data needed for adequate cardiac evaluation of the patient with MR. However, in cases where TTE image quality is poor, CMR may be of value in MR evaluation. CMR produces highly accurate data on LV volumes, RV volumes, and LVEF, as well as an assessment of regurgitant fraction for estimating MR severity.6–9 However, outcome data on large numbers of patients have been derived from echocardiography, and it is uncertain whether CMR data can be used interchangeably with echocardiographic data in predicting outcomes. CMR is less helpful in establishing mitral pathoanatomy. Downloaded from http://ahajournals.org by on October 7, 2026