Lutembacher's syndrome

Synonym: atrial septal defect with mitral stenosis syndrome

What is Lutembacher's syndrome?¹

The definition has changed and continued to vary. Lutembacher's syndrome is sometimes stated as referring to a congenital atrial septal defect (ASD) complicated by acquired mitral stenosis. A different definition used is any combination of ASD (congenital or iatrogenic) and MS (congenital or acquired). With percutaneous balloon mitral valvuloplasty for acquired MS, residual iatrogenic ASD secondary to trans-septal puncture is more common than congenital ASD.

Mitral regurgitation is also sometimes included in the spectrum of heart defects.

There is usually marked right ventricular hypertrophy and failure, and reduced blood flow to the left ventricle because blood flows back to the right atrium through the ASD.

Lutembacher's syndrome epidemiology²

Lutembacher's syndrome is very rare. The exact prevalence is not known.

Lutembacher's syndrome is more common in areas with higher prevalence of rheumatic heart disease, and therefore more common in Southeast Asia. In developing countries with a high prevalence of rheumatic heart disease, a history of rheumatic fever has been reported in 40% of patients with Lutembacher's syndrome.

Lutembacher's syndrome may also occur with percutaneous balloon mitral valvuloplasty for acquired MS. Residual iatrogenic ASD secondary to trans-septal puncture is more common than congenital ASD.¹

The syndrome can present at any age but most often in young adults. There is an increased prevalence in females because ASD and rheumatic MS are both more common in females.

Lutembacher's syndrome symptoms (presentation)

See separate article Cardiovascular History and Examination.

• It can present at any age.

• Patients may remain asymptomatic for many years.

• Symptoms are mainly due to the atrial septal defect (ASD). Signs and symptoms vary according to the size of the ASD.

• Pulmonary congestion and symptoms due to right ventricular failure: weight gain, ankle oedema, right upper quadrant pain and ascites.

• The patient may have a history of rheumatic fever.

• Fatigue and reduced exercise tolerance result from decreased systemic blood flow.

• Palpitations: these are a common presenting symptom. Predisposition to atrial arrhythmias (atrial fibrillation is very common).

• Symptoms caused by mitral stenosis (paroxysmal nocturnal dyspnoea, orthopnoea and haemoptysis) are seen less frequently in Lutembacher's syndrome than in isolated mitral stenosis. They are more common in Lutembacher's syndrome patients with a small ASD.

Signs

• Arterial pulse: small volume, may be irregular if atrial arrhythmia.

• Jugular venous pulse: distended jugular veins, even in the absence of right heart failure. Large a waves if in sinus rhythm.

• Left parasternal heave. May be a tapping apex impulse due to the palpable, loud first heart sound of mitral stenosis.

• Heart sounds:
  

  • May be features of mitral stenosis (loud first heart sound, opening snap and a mitral early-mid diastolic murmur) but these are variable.

  • The second heart sound may be widely split.

  • Third and fourth heart sounds of right ventricular origin may be audible at the left sternal border and are louder with inspiration.

• Systolic murmurs:
  

  • A pulmonary flow murmur due to increased flow across the pulmonic valve.

  • Tricuspid regurgitation: lower left parasternal area. Due to the displaced tricuspid valve secondary to right ventricular dilatation (common). Increases with inspiration.

• Mid diastolic murmurs:
  

  • Left lower sternal border or at apex: increased flow across the tricuspid valve.

  • Apex: mitral stenosis.

• Continuous murmur in the lower right sternal area: continuous shunting of blood across a small ASD in the presence of severe mitral stenosis.

• Ascites, hepatomegaly and dependent oedema (if right heart failure).

Differential diagnosis

• Atrial septal defect (ASD).

• Other cause of left-to-right shunt and pulmonary congestion, eg, ventricular septal defect (VSD), patent ductus arteriosus.

• Mitral stenosis.

• Patent foramen ovale.

• Pulmonary hypertension.

• Tricuspid regurgitation.

Investigations³

• CXR: pulmonary plethora, left atrial enlargement, right ventricular enlargement, pulmonary artery enlargement, pulmonary vascular congestion.

• Electrocardiogram: sinus rhythm or atrial fibrillation. Otherwise, P waves tall, broad or bifid in lead II with a deep negative force in V1 suggesting enlargement of both atria. QRS shows right-axis deviation, right ventricular hypertrophy, complete or incomplete right bundle-branch block.

• Transthoracic or transoesophageal echocardiography: transoesophageal echocardiography remains the gold standard for diagnosis and evaluation.

• Cardiac catheterisation: not performed routinely. Can be used to evaluate the severity of the atrial septal defect (ASD), detect reversible pulmonary hypertension, measure the mitral valve area and evaluate coronary artery disease in high-risk patients.

Lutembacher's syndrome treatment and management

Management of:

• Right-sided heart failure.

• Arrhythmias.

• Infective endocarditis.

Prevention of infective endocarditis: high risk for infective endocarditis.

Surgical

• Surgery is now performed early rather than late because the rates of heart failure and cardiac arrhythmia increase with age. Patients with pulmonary hypertension and irreversibly increased pulmonary vascular resistance (Eisenmenger's syndrome) invariably develop progressive right-sided heart failure after ASD closure.

• Percutaneous management of the Lutembacher syndrome (percutaneous trans mitral commissurotomy (PTMC) and ASD device closure) is an effective and low risk procedure and avoids considerable morbidity. ^{4 5}

• Mitral valvuloplasty alone can be complicated by development of ASD secondary to trans-septal puncture performed as a part of the procedure.

Complications¹

• Right heart failure.

• Atrial arrhythmias.

• Pulmonary hypertension.

• Infective endocarditis. The presence of MS, especially when accompanied by mitral regurgitation, increases susceptibility to infective endocarditis, in contrast to the low incidence of infective endocarditis in uncomplicated ASD.

• Eisenmenger's syndrome (very uncommon with a large atrial septal defect (ASD) and a high left atrial pressure due to the mitral stenosis).

Prognosis¹

Mortality and morbidity rates are related to the relative severity of the individual lesions. Survival to advanced age has also been reported.

The long-term natural history of ASD is unfavourably influenced by MS, which augments the left-to-right shunt and predisposes to atrial fibrillation and right ventricular failure.

Early diagnosis and surgical treatment improves the prognosis:

• If diagnosed at a late stage, pulmonary hypertension and heart failure develop and the prognosis is much worse.

• If diagnosed before the development of pulmonary hypertension and heart failure, ASD closure with mitral valve replacement bears a good prognosis and prolongs survival.