What are the symptoms and treatment options for mitral stenosis?

Symptoms and Treatment of Mitral Stenosis

The primary symptoms of mitral stenosis include exertional dyspnea, fatigue, palpitations, hemoptysis, and signs of right heart failure, while treatment options include medical therapy with diuretics and rate control medications, percutaneous mitral commissurotomy for suitable candidates, or surgical valve repair/replacement for severe or complicated cases. 1, 2

Clinical Presentation

Common Symptoms

• Exertional dyspnea is the most common symptom, often developing gradually as patients unconsciously reduce their activity levels 1
• Fatigue and palpitations are frequently reported, especially with development of atrial fibrillation 1
• Hemoptysis may occur due to pulmonary hypertension and rupture of bronchial veins 1
• Symptoms may be absent or subtle even in severe mitral stenosis due to enhanced left atrial compliance 1
• Family members may report diminished activity levels that patients themselves are unaware of 1

Physical Examination Findings

• Diastolic rumbling murmur best heard at the apex with the patient in left lateral position 1
• Opening snap followed by a low-pitched diastolic murmur 1
• Loud S1 in early disease (becomes softer as valve calcifies) 1
• Signs of pulmonary hypertension and right heart failure in advanced disease 1
• Atrial fibrillation is common, especially as disease progresses 1

Diagnostic Classification

• Mild: mitral valve area >1.5 cm², mean gradient <5 mmHg, pulmonary artery systolic pressure <30 mmHg 1
• Moderate: mitral valve area 1-1.5 cm², mean gradient 5-10 mmHg, pulmonary artery systolic pressure 30-50 mmHg 1
• Severe: mitral valve area <1 cm², mean gradient >10 mmHg, pulmonary artery systolic pressure >50 mmHg 1

Medical Management

Symptom Relief

• Diuretics can improve symptoms by reducing pulmonary congestion and peripheral edema 1, 2
• Beta-blockers, calcium channel blockers (verapamil, diltiazem), or digoxin help control heart rate in patients with atrial fibrillation 1, 2
• Heart rate control is particularly important as tachycardia shortens diastolic filling time, worsening symptoms 2

Anticoagulation

• Anticoagulation with vitamin K antagonists (target INR 2-3) is indicated for patients with:
  • Atrial fibrillation (paroxysmal or permanent) 1
  • History of systemic embolism 1, 2
  • Left atrial thrombus 1
  • Dense spontaneous echo contrast in the left atrium 1, 2
  • Enlarged left atrium (M-mode diameter >50 mm or volume >60 mL/m²) 1, 2
• NOACs are not recommended for patients with mitral stenosis and atrial fibrillation 1

Interventional Treatment

Percutaneous Mitral Commissurotomy (PMC)

• First-line intervention for symptomatic patients with favorable valve anatomy 2
• Indications include:
  • Symptomatic patients (NYHA class II-IV) with moderate to severe mitral stenosis 1
  • Asymptomatic patients with high risk of thromboembolism or hemodynamic decompensation 1
  • Pulmonary artery systolic pressure >50 mmHg at rest or >60 mmHg with exercise 1
• Contraindications include:
  • Left atrial thrombus 1
  • More than mild mitral regurgitation 1
  • Severe or bicommissural calcification 1
  • Absence of commissural fusion (degenerative mitral stenosis) 1
  • Severe concomitant aortic valve disease or severe tricuspid stenosis/regurgitation 1

Surgical Intervention

• Mitral valve repair (commissurotomy) or replacement is indicated when:
  • PMC is contraindicated or unsuccessful 1
  • Valve morphology is unfavorable for PMC 1
  • Severe symptoms persist despite medical therapy 3
  • Concomitant cardiac surgery is required 1
• Valve replacement is the only option for degenerative mitral stenosis with severe calcification 1, 4

Follow-up and Monitoring

• Asymptomatic patients with significant mitral stenosis should have yearly clinical and echocardiographic examinations 1
• Patients with moderate stenosis can be followed at longer intervals (2-3 years) 1
• Exercise testing may be useful to unmask symptoms or assess exercise capacity in apparently asymptomatic patients 1

Special Considerations

• In elderly patients with rheumatic mitral stenosis and high surgical risk, PMC may be a useful palliative option 1
• Degenerative mitral stenosis (due to severe annular calcification) is becoming more common in developed countries and is not amenable to PMC 4, 5
• Transcatheter mitral valve implantation may be an emerging option for inoperable patients with degenerative mitral stenosis 1