Arrhythmogenic right ventricular cardiomyopathy

Background

• Autosomal dominant condition characterised by abnormal cardiac proteins (potentially desmosomal proteins) which causes breakdown of the hear muscle and replacement with fibrous/fatty tissue
  • Usually affects the right side but can affect both
  • Uncommon 1:2000
• These patients are at increased risk of ventricular arrhythmias, sudden death (serious cause of sudden death in <35 year group- and accounting for around 20% of sudden cardiac deaths) and right heart failure

Pathogenesis

• Four phases
  • Concealed phase
    • Small changes to the right side of the heart.  Patients are asymptomatic
  • Overt phase
    • Symptomatic right ventricular arrhytmias associated with functional and structural changes
  • Right heart strain/failure
    • Disease affecting the entire right ventricle
  • Left ventricular impairment

Presentation

• Usually presents in young adult males
• Occasionally, patients may present with symptoms such as
  • Arrhythmias e.g. syncope, palpitations, light-headedness/dizziness
  • Shortness of breath
  • Leg swelling/abdominal distention/ascites (Right heart strain)
• Unfortunately, many patients are asymptomatic until sudden cardiac death (diagnosis made at autopsy)

Investigations

• ECG may show a slightly broad QRS complex and inverted T waves in the right precordial leads (II < III; V1 > V2)
  • Left bundle branch block is common
• ECHO and MRI scans can confirm the diagnosis (fatty deposits seen on MRI)

Management

• Implantable defibrillator is an option for patients at risk of sudden death (drug treatments such as sotalol or amiodarone + beta blocker may help)