Clinical Assessment & Severity Grading
History — symptoms of decompensation
Dyspnoea & orthopnoea (pulmonary congestion), haemoptysis, easy fatigability and syncope (fixed low output), palpitations (AF), symptoms of right heart failure (swelling, abdominal distension).
🩺 Examination signs
- Typical mitral facies (malar flush) · mild peripheral cyanosis.
- Loud S₁ (a pliable, non-calcified valve snaps shut from a high LA pressure; a soft S₁ suggests a calcified valve).
- Opening snap (OS) — a shorter S₂–OS interval means more severe stenosis (higher LA pressure opens the valve sooner).
- Low-pitched, rumbling mid-diastolic murmur with presystolic accentuation (if in sinus rhythm — reflects preserved atrial kick).
- Loud P₂ and a right parasternal heave (pulmonary hypertension & RV hypertrophy); signs of a tricuspid murmur / raised JVP with RV failure.
| Investigation | Findings |
|---|---|
| ECG | P-mitrale (broad, bifid P in II) = LA enlargement; AF; RVH (dominant R in V₁–V₂) |
| Echocardiography | Valve area (planimetry / pressure-half-time), reduced anterior-leaflet motion, LA enlargement/thrombus, PAP, thickened valve, diastolic doming |
| Chest X-ray | ↑ Cardiothoracic ratio, straightening of the left heart border & double density (LA enlargement), elevated left main bronchus, splaying of the carina, upper-lobe diversion |
📊 Grades of mitral stenosis
| Severity | Valve area (cm²) | Mean gradient (mmHg) | PAP (mmHg) | Symptoms |
|---|---|---|---|---|
| Normal | 4–6 | <2 | 10–20 (normal) | — |
| Mild | >1.5 | <5 | <30 | Absent |
| Moderate | 1.0–1.5 | 5–10 | 30–50 | NYHA II |
| Severe | <1.0 | >10 | >50 | NYHA III–IV |
A multidisciplinary team — anaesthetist, obstetrician, cardiologist and paediatrician — should plan the delivery. Follow the relevant ANC / cardiac-disease-in-pregnancy guidance for the mode and timing of delivery.