Overview

Mitral stenosis causes an obstruction to blood flow from the left atrium to left ventricle usually as a result of rheumatic heart disease. The stenosis results in increased pressure in the left atrium, pulmonary vasculature and right side of heart. Mitral valve disease is a frequent cause of heart failure and death.

Valvular Heart Disease

• Endocarditis
• Aortic Valve Disease
• Mitral Valve Disease
  • Mitral Stenosis
  • Mitral Regurgitation
• Pulmonary Valve Disease
• Tricuspid Valve Disease

Aetiology and Risk Factors

Aetiology

• Rheumatic fever leading to rheumatic heart disease (95% of cases)
• Congenital

Risk Factors

• Streptococcal infection
• Ergot medications
• Serotogenic medications
• SLE
• Amylodoisis

Clinical Manifestation

• Exertional dyspnoea
• Decreased excercise tolerance
• Haemoptysis
• Chest pain
• Fatigue
• History of rheumatic fever
• Malar flush
• Signs of right-sided heart failure
  • ascites
  • raised JVP
  • peripheral oedema
• Thromboembolic event “Stroke”
• Hoarseness (recurrent laryngeal nerve compressed)
• Dysphagia (esophagus compressed)

This image series is only available to members

Cardiovascular Examination

• Malar flush
• Pulse
  • Weak pulse due to reduced strove volume
  • Atrial fibrillation
• Left parasternal heave (from right ventricular hypertrophy)
• Auscultation – Mitral valve (Apex – left 5th intercostal space mid-clavicular)
  • Pre systolic murmur precedes S1, a result of increase blood flow from atrial contraction
  • Opening snap of the mitral valve following S2 (closure of the aortic and pulmonic valves) is the opening of the stenotic mitral valve (SNAP)
  • Long murmur during Diastole (longer in chronic mitral stenosis)
  • Low-pitched diastolic rumble that is most prominent at the apex.

Diagnosis

Symptoms and signs similar to mitral stenosis

• left atrial myxoma
• prosthetic valve obstruction
• Cor tratriatum

Investigations

• ECG
  • Atrial fibrillation
  • Left atrial enlargement – P mitrale
  • Right ventricular hypertrophy – Right axis deviation
• Chest X-ray
  • Straight or convex L heart border
  • Double shadow of LA behind RA
  • Splaying of carina
  • Dilated upper lobe veins
  • Prominent pulmonary conus
  • Pulmonary haemosiderosis
• Trans-thoracic echocardiography
• Transoesophageal echocardiography
• Cardiac catherization

Diagnosis

Echocardiography — A transthoracic echocardiogram is indicated in patients with signs or symptoms of MS to establish the diagnosis, quantify the hemodynamic severity determine the etiology, and assess concomitant valve disease.

Treatment

Medication – Preload reduction

• No treatment generally required if asymptomatic but monitoring is important
• Diuretics and sodium

Surgery

• Balloon valvotomy
  • moderate to severe symptomatic disease
• Diuretic
• Valve replacement or repair
  • Mechanical
  • Bioprosethetic

Complications and Prognosis

Complications

• Atrial Fibrillation
• Stroke
• Warfarin-induced haemorrhage
• Systemic Embolism – due to thrombus formation in the right atrium
• Infective endocarditis
• Functional tricuspid reguritation

Prognosis

• With continuous monitoring and ppropriate treatment prognosis is excellent
• Death from Mitral stenosis is oftne due to progressive right-sided heart failure and/or pulmonary edema