Discuss the aetiology, clinical features, investigations and management of valvular heart disease.

Introduction

Valvular heart disease remains disproportionately important in India because of the continuing burden of rheumatic heart disease, which produces valve lesions in young adults — in contrast to the degenerative disease of the elderly seen in Western populations.

Mitral Stenosis

Aetiology: RHEUMATIC in over 95% of cases — the classic rheumatic valve lesion. Others: congenital, severe mitral annular calcification, carcinoid, SLE (Libman–Sacks).

Pathophysiology: the normal mitral valve area is 4–6 cm². Narrowing raises left atrial pressure, which transmits back to the pulmonary circulation → pulmonary hypertension → right ventricular hypertrophy and failure. The left ventricle is protected and remains normal, which is why symptoms are those of pulmonary congestion and low output rather than LV failure.

Clinical features:

• Exertional dyspnoea, orthopnoea, PND; fatigue and low output symptoms
• HAEMOPTYSIS — from rupture of bronchial veins; a classical feature
• Atrial fibrillation — from left atrial dilatation; often precipitates decompensation
• Systemic embolism, particularly stroke — the risk is high, especially with AF
• Hoarseness (Ortner's syndrome) — left recurrent laryngeal nerve compression by the dilated left atrium
• Malar flush ("mitral facies"); tapping apex (palpable first heart sound); right ventricular heave
• Auscultation: LOUD FIRST HEART SOUND, OPENING SNAP, and a LOW-PITCHED RUMBLING MID-DIASTOLIC MURMUR with PRESYSTOLIC ACCENTUATION (the accentuation disappears in atrial fibrillation), best heard at the apex, in the left lateral position, with the bell, on expiration
• A SHORTER interval between S2 and the opening snap indicates MORE SEVERE stenosis (higher left atrial pressure opens the valve earlier) — an elegant and frequently examined point

Investigations:

• ECG — P mitrale (broad bifid P wave), atrial fibrillation, right ventricular hypertrophy
• chest X-ray — straightening of the left heart border, double right heart border, splayed carina, pulmonary venous congestion, valve calcification
• echocardiography with valve area and gradient is definitive.

Management:

• diuretics for congestion
• rate control (beta-blockers) — which improves filling by prolonging diastole
• anticoagulation for atrial fibrillation, previous embolism or left atrial thrombus — WARFARIN, not a DOAC, in rheumatic mitral stenosis
• penicillin prophylaxis against recurrent rheumatic fever. Intervention: percutaneous balloon mitral valvotomy — the procedure of choice for pliable, non-calcified valves without significant regurgitation or left atrial thrombus (and highly successful in the young Indian rheumatic population)
• otherwise surgical commissurotomy or valve replacement.

Mitral Regurgitation

Aetiology:

• rheumatic
• mitral valve prolapse (the commonest cause in the West)
• ischaemic (papillary muscle dysfunction or rupture)
• infective endocarditis
• dilated cardiomyopathy with annular dilatation (functional)
• connective tissue disease.

Clinical features:

• exertional dyspnoea, fatigue, palpitations
• displaced hyperdynamic apex
• soft S1, third heart sound
• PANSYSTOLIC MURMUR at the apex RADIATING TO THE AXILLA, blowing and high-pitched, unchanged by respiration.

Acute severe MR (papillary muscle rupture after infarction, endocarditis) causes sudden pulmonary oedema and cardiogenic shock, often with only a short, soft murmur because pressures equalise rapidly — a dangerous trap.

Management:

• treat heart failure (ACE inhibitors, diuretics)
• surgery (repair is preferred to replacement) for severe MR with symptoms, or asymptomatic with LV dysfunction (EF < 60%) or LV dilatation
• transcatheter edge-to-edge repair in selected high-risk patients.

Aortic Stenosis

Aetiology:

• degenerative calcific disease (the commonest in the elderly)
• bicuspid aortic valve (presenting earlier, in the 50s–60s)
• rheumatic (usually with mitral involvement).

Clinical features — the classic triad ("SAD"), each with prognostic weight:

• Syncope (exertional) — average survival about 3 years
• Angina — about 5 years
• Dyspnoea (heart failure) — about 2 years

The onset of symptoms marks a sharp fall in survival and is the trigger for intervention.

Signs:

• slow-rising, low-volume pulse (pulsus parvus et tardus), narrow pulse pressure, heaving (pressure-loaded) undisplaced apex, thrill in the aortic area
• EJECTION SYSTOLIC MURMUR at the right second intercostal space RADIATING TO THE CAROTIDS
• soft or absent A2 and reversed splitting of S2 in severe disease
• fourth heart sound.

Investigations:

• ECG — LVH with strain
• chest X-ray — post-stenotic aortic dilatation, calcification
• echocardiography — valve area, peak velocity and mean gradient define severity.

Management:

• no medical therapy alters the natural history — treat comorbid hypertension cautiously.
• Aortic valve replacement (surgical) or TAVI (transcatheter aortic valve implantation) for symptomatic severe stenosis, or asymptomatic severe stenosis with LV dysfunction.
• TAVI has transformed treatment for elderly and high-risk patients.

Aortic Regurgitation

Aetiology: valve disease — rheumatic, bicuspid valve, infective endocarditis; or aortic root dilatation — Marfan syndrome, hypertension, syphilitic aortitis (historically important in India), ankylosing spondylitis, aortic dissection.

Clinical features: long asymptomatic period, then exertional dyspnoea, palpitations and angina. The signs arise from the wide pulse pressure:

• COLLAPSING ("water-hammer") PULSE; wide pulse pressure
• Corrigan's sign (visible carotid pulsation), de Musset's sign (head nodding), Quincke's sign (nail bed capillary pulsation), Traube's sign ("pistol shot" femoral sounds), Duroziez's sign (to-and-fro femoral murmur), Müller's sign (uvular pulsation)
• Displaced, hyperdynamic, volume-loaded apex
• EARLY DIASTOLIC MURMUR at the left sternal edge, best heard leaning forward in expiration; Austin Flint murmur (a mid-diastolic rumble at the apex from the regurgitant jet striking the anterior mitral leaflet)

Acute severe AR (endocarditis, dissection) causes sudden pulmonary oedema with a short murmur, tachycardia and NO peripheral signs — because there is no time for the ventricle to dilate. It is a surgical emergency.

Management:

• vasodilators (ACE inhibitors, nifedipine) for symptomatic patients unfit for surgery
• surgery for symptoms, or asymptomatic with LV dysfunction (EF < 50%) or progressive LV dilatation
• aortic root replacement where the root is dilated (as in Marfan syndrome).

Right-sided murmurs (tricuspid and pulmonary) increase on INSPIRATION — Carvallo's sign.