Eisenmenger Syndrome

Eisenmenger syndrome occurs when pulmonary hypertension, caused by high pulmonary vascular resistance due to reversal of an intracardiac shunt. With a shunt at either ventricular or atrial level, due to increased rates of flow through the lungs reactive pulmonary hypertension develops. This begins in early life and causes progressive pulmonary vascular resistance. At some point the pulmonary vascular resistance becomes equal to or greater than systemic vascular resistance, causing the shunt to be reversed or bidirectional.¹

The frequency of pulmonary hypertension and development of reversed shunting vary depending on the specific heart defect and operative interventions. Early development of Eisenmenger syndrome is more commonly associated with persistent truncus arteriosus and unrestricted pulmonary blood flow, common atrioventricular canal, ventricular septal defect, patent ductus arteriosus and transposition of the great arteries. It is less common and occurs later in life in patients with a large secundum atrial septal defect.

• The frequency of pulmonary hypertension and the development of reversed shunting vary depending on the specific heart defect and operative interventions.
• 50% of infants with a large, non-restrictive VSD or PDA develop pulmonary hypertension by early childhood.
• 10% of patients with a large secundum ASD progress to pulmonary hypertension but usually not until after the third decade of life.

• Dyspnoea, fatigue, syncope
• Chest pain
• Haemoptysis
• Examination reveals:
  • Cyanosis, clubbing and plethora
  • Right ventricular heave with palpable, loud pulmonary component of the second heart sound
  • Loud second heart sound with a narrow split
  • Ejection systolic murmur audible along the left sternal border
  • Graham Steel murmur: a diastolic murmur audible along the left sternal border due to functional incompetence of the pulmonary valve in patients with pulmonary hypertension. The Graham Steel murmur is a high-pitched, decrescendo murmur, loudest during inspiration.

• Primary pulmonary hypertension
• Cyanotic congenital heart disease, e.g. Fallot's tetralogy.

• Full blood count, renal function and electrolytes, uric acid, liver function tests (raised conjugated bilirubin)
• Arterial blood gases
• ECG: almost always abnormal; shows features suggestive of right heart hypertrophy (with tall R wave in V1, deep S wave in V6, ST and T wave abnormalities, P pulmonale) as well as abnormalities associated with the underlying defect
• Chest x-ray: radiological features of particular condition such as patent ductus arteriosus, ventricular septal defect but the lungs are no longer plethoric
• Echocardiogram
• Cardiac catheterisation may be of value to confirm the severity of pulmonary vascular hypertension, degree of shunting and any co-existing coronary artery anomalies

• Treat heart failure and arrhythmias.
• Calcium-channel blockers (may increase the right to left shunt), antiplatelet agents and anticoagulants have not been shown to be beneficial and may cause further complications, e.g. hypotension, worsening cyanosis, increased hyperuricaemia or haemorrhage.
• Some groups will require antibiotic prophylaxis for prevention of infective endocarditis but this will depend on the underlying heart abnormality.
• Patients with significant polycythaemia may be helped by repeated venesection and volume replacement.
• Chronic use of oxygen or pulmonary vasodilators is controversial and under investigation.
• Ultimately, heart-lung transplant may be indicated.²

• Fetal mortality rate is approximately 25% and the maternal mortality rate is over 50% and so affected women should be strongly advised against pregnancy.
• Tubal ligation is recommended for contraception. Intrauterine devices should be avoided as they may cause significant menorrhagia and increase the risk of endocarditis.
• The risk of congenital heart defects in offspring is approximately 10% but depends on the initial cardiac defect.

• Polycythaemia, hyperviscosity syndrome and bleeding disorders
• Brain abscess, transient ischaemic attacks, stroke
• Hyperbilirubinaemia may cause gallstones and hyperuricaemia may lead to nephrolithiasis and secondary gout.
• Hypertrophic osteoarthropathy

• Survival depends on ventricular function but sudden death is always a threat.
• Commonly survive into adulthood with complications of cyanotic heart disease.
• Patients not diagnosed until adulthood have a poor prognosis.³