Mitral Valve Disease – Summary

almostadoctor app banner for android and iOS almostadoctor iPhone, iPad and android apps almostadoctor iOS app almostadoctor android app
Mitral stenosisMitral regurgitation
Causes
  • Rheumatic heart disease (Group A beta haemolytic streptococcus)
  • Others : congenital, calcification/fibrosis in elderly, carcinoid tumour metastasizing to lung
PathophysiologyTo maintain CO, left atrial pressure↑>> left atrial hypertrophy and dilatation >> pulmonary venous, arterial and right heart pressure ↑ >> pulmonary oedema >> pulmonary HTN >> right ventricular hypertrophy, dilatation failure and subsequent tricuspid regurgitation
  • Mitral valve regurgitation > left atrial dilatation (but in acute, left atrium does not allow much dilatation, there will be rise in left atria pressure >> pulmonary oedema)
  • Stroke volume ↓ due to regurgitation, thus LV hypertrophy to increase stroke volume and hence CO
  • As time goes by , R sided HF
Symptoms
  • No symptoms until orifices <2cm2
    • Due to pulmonary hypertension: dyspnoea, haemoptysis, recurrent bronchitis
  • Eventually right HF: fatigue, leg swelling
    • Due to large left atrial, favours AF: palpitations , systemic emboli
  • Due to pulmonary oedema or left heart failure: dyspnoea, orthopnoea, fatigue and lethargy
  • Due to the stoke volume: palpitations
  • Subacute infective endocarditis
Signs
  • Face : Mitral facies / malar flush (due to ↓CO)
  • Pulse : AF
  • RV : heaving, sustained
  • Apex: localised, tapping
  • HS: Loud S1, loud P2(pulmonary HTN), opening snap
  • Murmurs: mid diastolic murmur rumbling at apex
  • Pulse : sinus rhythm or AF
  • Apex : forceful, displaced, systolic thrill
  • Sounds: Soft S1, split S2, loud P2 . maybe a mid-systolic click (sudden prolapse of the valve)
  • Murmurs : pansystolic , radiating to axilla
Investigation1.     CXR

  • Small heart with enlarged left atrium
  • Calcified mitral valve
  • Sign of pulmonary oedema

2.     ECG

  • AF
  • Bifid P wave/P mitrale
  • Right axis deviation/ tall R waves in lead V1 (Right ventricle hypertrophy)

3.     Echocardiogram

4.     Cardiac catherisation (indicated in):

  • Previous valvotomy, sign of other valve disease, angina, severe pulmonary hypertension, calcified mitral valve
1.     CXR

  • Left atrial and left ventricular enlargement
  • Increased cardiac thoracic ratio
  • Valve calcification

2.      ECG

  • Bifid P wave
  • Left ventricular hypertrophy (tall R wave in leads 1, V6 and deep S wave is V1 and V2)
  • AF might be present

3.     Echocardiogram + Doppler

4.     Cardiac catherization

TreatmentPharmacological:

  • AF: digoxin and anticoagulation
  • Pulmonary oedema : diuretics

Surgical: ( 4 options)

  • Trans-septal balloon valvotomy (pliable, non-calcified valve)
  • Closed valvotomy
  • Open valvotomy
  • Mitral valve replacement

(if 1.mitral regurg also present; 2. Badly diseased or calcified stenotic valve 3. Moderate or severe mitral stenosis and thrombus in the left atrium despite anticoagulation)

Pharmacological

  • Prophylaxis against IE
  • If fast AF : rate control + anticoagulated
  • Pulmonary oedema / HF; diuretics
  • ACE inhibitor

Surgical :

  • For deteriorating symptoms
  • Aim to repair or replace valve be4 LV irreversibly impaired (early intervention!)

Percutaneous mitral valve repair (Mitraclip)

  • New
  • Appropriate for patient unsuitable for cardiac surgery

References

  • Murtagh’s General Practice. 6th Ed. (2015) John Murtagh, Jill Rosenblatt
  • Oxford Handbook of General Practice. 3rd Ed. (2010) Simon, C., Everitt, H., van Drop, F.
  • Beers, MH., Porter RS., Jones, TV., Kaplan JL., Berkwits, M. The Merck Manual of Diagnosis and Therapy

Read more about our sources

Related Articles

Dr Tom Leach

Dr Tom Leach MBChB DCH EMCert(ACEM) FRACGP currently works as a GP and an Emergency Department CMO in Australia. He is also a Clinical Associate Lecturer at the Australian National University, and is studying for a Masters of Sports Medicine at the University of Queensland. After graduating from his medical degree at the University of Manchester in 2011, Tom completed his Foundation Training at Bolton Royal Hospital, before moving to Australia in 2013. He started almostadoctor whilst a third year medical student in 2009. Read full bio

Leave a Reply