Mitral Stenosis

 

• Causes

  • Rheumatic valve disease. Though it can affect any valve, mitral stenosis is the most common valve defect that results.
  • Calcification
  • Autoimmune disease: RA, SLE.
  • Carcinoid syndrome.
  • Congenital
  • Mucopolysaccharidoses
  • Endocardial fibroelastosis.

• Signs and symptoms

  Asymptomatic or:

  • SOB, orthopnea, and PND.
  • Haemoptysis: bronchial vein rupture due to pulmonary HTN.
  • Pink frothy sputum: pulmonary oedema.
  • Fatigue.
  • Features of AF (present in >50%): palpitations and irregularly irregular pulse, emboli (e.g. stroke).
  • RVF symptoms.
  • Hoarseness from recurrent laryngeal nerve compression.

  Signs:

  • Mid-diastolic murmur heard at apex with bell. Follows opening snap in early diastole.
  • Loud S1.
  • Tapping apex beat.
  • Malar flush.
  • RVF signs.

• Investigations

  Echo is diagnostic.

  ECG:

  • AF
  • P-mitrale if in sinus rhythm: bifid/broad P-wave due to large left atrium.
  • RVH

  CXR:

  • Enlarged left atrium: double right heart border.
  • Valve calcification

• Management

  Medical:

  • Anticoagulation if there is AF, thrombus in left atrium, or prior thrombus.
  • Diuretics or long-acting nitrates for SOB, and β-blockers or rate-limiting CCBs to improve exercise tolerance.
  • Annual echo.

  Surgery:

  • Indications: severe symptoms or complications.
  • Percutaneous balloon mitral commissurotomy (PMC) is 1st line choice. Commissurotomy (aka valvotomy, valvulotomy) involves opening up the valve at the junction of its leaflets. Contraindication: left atrial thrombosis.
  • Other options: open surgical commissurotomy or valve replacement.

• Complications

  • Left atrial enlargement → oesophageal and recurrent laryngeal nerve compression, AF.
  • Pulmonary HTN, RVF, tricuspid or pulmonary regurgitation.
  • Infective endocarditis.