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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 e116

CLINICAL STATEMENTS AND GUIDELINES for rate control versus rhythm control is dependent on multiple factors, including the duration of AF, hemodynamic response to AF, LA size, prior episodes of AF, and history of embolic events. It is more difficult to achieve rhythm control in patients with rheumatic MS because the rheumatic process itself may lead to progressive fibrosis and enlargement of the atria, fibrosis of the internodal and interatrial tracts, and damage to the sinoatrial node. 3.	 The use of negative dromotropic agents for the treatment of symptoms in patients with rheumatic MS in normal sinus rhythm has been controversial. Although a reduction in heart rate and prolongation of the diastolic filling period will decrease the transmitral mean gradient, studies have shown that treatment with beta blockade may not improve or may even decrease exercise tolerance, most likely because of the limitation of the cardiac output attributable to a limited stroke volume and chronotropic incompetence.9–11 Nonetheless, there are now several randomized trials that have examined beta blockers and ivabradine in patients with rheumatic MS and have shown that either drug can increase exercise duration and improve symptoms,2–15 To explain these differences, the earlier trials that found no benefit of beta blockers were performed in older patients with underlying chronotropic incompetence, whereas the randomized trials showing benefit were performed primarily in younger patients with higher resting and exerciseinduced heart rates. Thus, the use of beta blockers or ivabradine to improve symptoms may be effective only in patients who do not have underlying chronotropic incompetence. When medical therapy is considered for relief of symptoms in patients with rheumatic MS, it must be remembered that intervention with PMBC relieves symptoms in those patients with an appropriate valve morphology.

6.2.3 Intervention

Recommendations for Intervention for Rheumatic MS Referenced studies that support the recommendations are summarized in Online Data Supplements 21 to 24.

COR LOE Recommendations

1 A 1.  In symptomatic patients (NYHA class II, III, or IV) with severe rheumatic MS (mitral valve area ≤1.5 cm2, Stage D) and favorable valve morphology with less than moderate (2+) MR* in the absence of LA thrombus, PMBC is recommended if it can be performed at a Comprehensive Valve Center.1–12

1 B-NR 2.  In severely symptomatic patients (NYHA class III or IV) with severe rheumatic MS (mitral valve area ≤1.5 cm2, Stage D) who 1) are not candidates for PMBC, 2) have failed a previous PMBC, 3) require other cardiac procedures, or 4) do not have access to PMBC, mitral valve surgery (repair, commissurotomy, or valve replacement) is indicated.6,7,13 2a B-NR 3.  In asymptomatic patients with severe rheumatic MS (mitral valve area ≤1.5 cm2, Stage C) and favorable valve morphology with less than 2+ MR in the absence of LA thrombus who have elevated pulmonary pressures (pulmonary artery systolic pressure >50 mm Hg), PMBC is reasonable if it can be performed at a Comprehensive Valve Center.14

2b C-LD 4.  In asymptomatic patients with severe rheumatic MS (mitral valve area ≤1.5 cm2, Stage C) and favorable valve morphology with less than 2+/ MR* in the absence of LA thrombus who have new onset of AF, PMBC may be considered if it can be performed at a Comprehensive Valve Center.15

2b C-LD 5.  In symptomatic patients (NYHA class II, III, or IV) with rheumatic MS and an mitral valve area >1.5 cm2, if there is evidence of hemodynamically significant rheumatic MS on the basis of a pulmonary artery wedge pressure >25 mm Hg or a mean mitral valve gradient >15 mm Hg during exercise, PMBC may be considered if it can be performed at a Comprehensive Valve Center.16

2b B-NR 6.  In severely symptomatic patients (NYHA class III or IV) with severe rheumatic MS (mitral valve area ≤1.5 cm2, Stage D) who have a suboptimal valve anatomy and who are not candidates for surgery or are at high risk for surgery, PMBC may be considered if it can be performed at a Comprehensive Valve Center.17–19 *2+ on a 0 to 4+ scale according to Sellar’s criteria or less than moderate by Doppler echocardiography.20

Synopsis

The optimal treatment of patients with rheumatic MS is either PMBC or surgery (open or closed commissurotomy). Although these procedures can result in excellent outcomes by splitting open fused commissures to relieve stenosis, both the catheter-based and the surgical procedures require a high level of expertise and should be performed at experienced centers. In the United States, there has been a 7.5% decrease in the use of PMBC, accompanied by a 15.9% increase in complication rate.21 Excellent short- and long-term outcomes can be achieved with surgical commissurotomy, but surgical commissurotomy is not routinely or widely performed by most surgeons in the United States. Thus, in the clinical decision-making process for a patient with rheumatic MS, it is essential to know the results of the available interventional procedures. Mitral valve replacement is an option for treatment only if there is no other option and the patient has severe limiting symptoms (Figure 7).

Recommendation-Specific Supportive Text

1.	 Randomized trials have established the safety and efficacy of PMBC as compared with surgical closed or open commissurotomy in patients with a

Recommendations for Intervention for Rheumatic MS (Continued)

COR LOE Recommendations

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