Mitral Stenosis

Pathological narrowing of the mitral valve. Patients often present with symptoms of heart failure, or with palpitations or stroke (AF). There is a 2:1 female:male ratio.



  • Look for stigmata of endocarditis
  • Palmer erythema
  • Pulse may be irregularly irregular (AF), always look for bruises from warfarinsation if AF present.
  • Malar flush
  • Left parasternal heave (due to RV enlargement)
  • Signs of pulmonary hypertension (loud P2, functional TR with large CV waves)
  • Auscultation:
    • Loud S1 – closing snap of stenosed mitral valve.
    • Loud P2- secondary to pulmonary HTN
    • Mid diastolic murmur: best heard with the bell, with the patient in the left lateral decubitus position at end expiration. Low pitched murmur. Often can have an opening snap at the beginning of the murmur if the stenosed valves a mobile.
    • Graham -Steele murmur: pulmonary regurgitation secondary to raised pulmonary pressures from MS.


Signs of severe MS: AF, pulmonary HTN, signs of congestive heart failure, short gap between S2 and opening snap.


Severity MV area (cm2) Mean gradient (mmHg)
Mild >1.5 <5
Moderate 1.0-1.5 5-10
Severe <1.0 >10




  • Common: Rheumatic fever (90%)
  • Rare: congenital (isolated, cor-triatriatum, shones syndrome), degenerative mitral annular calcification, non-valvular (LA myxoma, IE with large thrombus)



Bedside: ECG (AF)

Bloods: Routine FBC & U&E, Blood cultures if ? IE

Functional: Echocardiogram +/- TOE if requiring to exclude LA appendage thrombus

Imaging: CXR: To ? Pulmonary congestion.

Invasive: Left and right heart catheterisation as work up prior to surgery.




Options include: observation, Percutaneous balloon mitral valvuloplasty (PBMV), or surgical repair/replacement.


Options for treatment depend upon whether the patient is symptomatic and to what severity the valve is stenosed.


Symptomatic patients with NYHA grade 2 symptoms or higher and moderate/severe stenosis should be offered PBMV, if valve unsuitable (assessed by wilkins score) then surgical replacement or repair should be considered.


Asymptomatic patients with moderate/severe MS and symptomatic patients with NYHA grade 2 symptoms and mild MS should be sent for exercise testing. If PAP >60mmHg or mean gradient >15mmHg or pulmonary wedge pressure >25mmHg then PBMV should be offered. If no worsening with exercise then follow up.



Written by Dr Thomas Craven


Resources used to write this document are listed in the references section of this webpage