What is the initial management for a patient with newly discovered mitral regurgitation (MR) from rheumatic disease?

Management of Newly Discovered Mitral Regurgitation from Rheumatic Disease

Begin with transthoracic echocardiography to quantify MR severity and assess valve morphology, followed by guideline-directed medical therapy for symptomatic relief, with surgical referral reserved for severe MR with symptoms or hemodynamic consequences. 1

Initial Diagnostic Assessment

Perform transthoracic echocardiography immediately to establish MR severity using quantitative measures: effective regurgitant orifice area (EROA), regurgitant volume, and valve area using planimetry for any coexistent mitral stenosis. 1, 2

• Assess left ventricular ejection fraction (LVEF), left ventricular end-systolic diameter (LVESD), left atrial volume, and pulmonary artery systolic pressure, as these parameters guide timing of intervention. 1, 2
• Evaluate valve morphology for thickened or calcified leaflets, subvalvular disease with chordal fusion and shortening, which predict durability of potential repair. 1
• Rule out left atrial thrombus with transesophageal echocardiography if atrial fibrillation is present or if embolic events have occurred. 1, 3
• Age and left atrial volume are independent predictors of MR progression in rheumatic disease, with left atrial enlargement potentially triggering secondary MR mechanisms. 4

Medical Management

Start diuretics as first-line therapy for fluid overload manifestations including lower extremity edema and pulmonary congestion. 2, 5

• Add ACE inhibitors or ARBs when heart failure symptoms are present, as part of guideline-directed medical therapy. 2, 5
• Consider aldosterone antagonists if symptoms persist despite initial therapy. 2
• Beta-blockers provide rate control if atrial fibrillation develops and reduce ventricular arrhythmia risk. 2
• Nitrates may provide acute relief for dyspnea when there is a large dynamic component to the MR. 2, 5
• Anticoagulation is mandatory if atrial fibrillation develops, as rheumatic MR carries high thromboembolic risk. 1

Critical pitfall: Rheumatic MR severity is dynamic and changes with loading conditions, blood pressure, volume status, and heart rate—always reassess severity after medical optimization before deciding on intervention. 2, 5

Surveillance Protocol

Patients with moderate MR require clinical evaluation every 6-12 months with annual echocardiography. 2, 6

• Patients with severe MR should have clinical evaluation every 6 months with annual echocardiography. 2
• Monitor for progression of MR severity, development of symptoms, changes in left ventricular size or function (LVEF ≤60% or LVESD ≥40 mm), and pulmonary hypertension (>50 mm Hg). 1, 2, 6
• New-onset atrial fibrillation is a reasonable indication for surgical intervention even in asymptomatic patients with severe MR. 1, 2
• Exercise echocardiography should be performed when exercise-induced symptoms are present to assess for dynamic worsening of MR. 1, 2, 6

Indications for Surgical Intervention

Surgery is indicated for all symptomatic patients with severe rheumatic MR regardless of left ventricular function. 1, 5

For asymptomatic patients, surgery is indicated when:

• LVEF ≤60% or LVESD ≥40 mm develops. 1, 5
• New-onset atrial fibrillation occurs. 1, 2
• Resting pulmonary artery systolic pressure exceeds 50 mm Hg. 1, 2

Mitral valve repair may be considered in rheumatic disease when a durable and successful repair is likely, but durability is limited by thickened or calcified leaflets and extensive subvalvular disease. 1 Freedom from reoperation at 20 years is only 50-60% even in experienced hands, with repair accomplished in approximately 22% of rheumatic patients. 1

Repair should be limited to patients with less advanced disease or when mechanical prosthesis cannot be used due to anticoagulation management concerns. 1 Otherwise, valve replacement is more appropriate given the progressive nature of rheumatic disease. 1

Multidisciplinary Team Approach

All intervention decisions should involve heart team discussion including cardiologists experienced in heart failure management, cardiac surgeons, and imaging specialists. 1, 5

• Referral to a comprehensive valve center with high repair rates (>80-90%) and low operative mortality (<1%) optimizes outcomes. 1, 5, 7
• The team should assess valve morphology, patient comorbidities, surgical risk, and reliability of long-term anticoagulation management. 1, 5

Special Considerations

Tricuspid regurgitation commonly coexists with rheumatic mitral disease and predicts poor survival, heart failure, and reduced functional capacity. 8 Tricuspid annuloplasty with a ring should be performed at initial mitral valve surgery if tricuspid annulus diameter is ≥3.5 cm, as isolated tricuspid surgery later carries poor outcomes. 8

Do not delay surgical intervention until symptoms become severe or left ventricular dysfunction occurs, as this leads to worse outcomes with higher operative mortality and reduced long-term survival. 2, 5, 7 The best results are obtained in asymptomatic patients operated on before irreversible ventricular dysfunction develops. 7