Arrhythmogenic right ventricular dysplasia

Synonyms

Arrhythmogenic right ventricular cardiomyopathy

Overview

Arrhythmogenic right ventricular dysplasia (ARVD, also known as arrhythmogenic right ventricular cardiomyopathy or ARVC)) is an inherited heart condition in which the muscle of the right ventricle of the heart is replaced by fat and/or scar tissue. It is characterized by hypokinetic areas involving the free wall of the right ventricle, with fibrofatty replacement of the right ventricular myocardium, with associated arrhythmias originating in the right ventricle. The condition is progressive and over time the right ventricle loses the ability to pump blood. Individuals with ARVD often develop abnormal heart rhythms known as arrhythmias, which can increase the risk of sudden cardiac arrest or death.

Symptoms

  • Ventricular tachycardia
  • Shortness of breath
  • Left branch block dilated myocardiopathy
  • Sudden heart attack
  • Palpitations
  • Chest palpitations
  • Dizziness
  • Fainting and shortness of breath
  • Sudden cardiac death can be the first sign of ARVD

Causes

ARVD is caused by genetic mutations in genes that instruct proteins to link one heart cell to the next. There is also some evidence that ARVD could be caused by an infection of the heart muscle. The genetic basis of ARVD is complex and not fully understood. There are different ways in which ARVD can be inherited. The most common pattern of inheritance for ARVD is autosomal dominant. This means that a mutation in only one copy of the disease-causing gene is sufficient to cause the condition. An individual with an autosomal dominant condition has a 50% risk to pass the mutation on to each child. Other individuals with ARVD have an autosomal recessive form. This means mutations in both copies of the gene must be present to have a predisposition to ARVD. Parents of an individual with an autosomal recessive condition each carry one mutated copy of the gene and are referred to as carriers. When two carriers of an autosomal recessive condition have children, each child has a 25% risk to inherit mutations and be affected. Genetic testing can help determine which pattern of inheritance an affected individual has.

The genetic basis of ARVD is complex and not fully understood. There are different ways in which ARVD can be inherited. The most common pattern of inheritance for ARVD is autosomal dominant. This means that a mutation in only one copy of the disease-causing gene is sufficient to cause the condition. An individual with an autosomal dominant condition has a 50% risk to pass the mutation on to each child. Other individuals with ARVD have an autosomal recessive form. This means mutations in both copies of the gene must be present to have a predisposition to ARVD. Parents of an individual with an autosomal recessive condition each carry one mutated copy of the gene and are referred to as carriers. When two carriers of an autosomal recessive condition have children, each child has a 25% risk to inherit mutations and be affected.[2] Genetic testing can help determine which pattern of inheritance an affected individual has.

Diagnosis

The differential diagnosis for the ventricular tachycardia due to ARVD include:

  • Genetic Evaluation of Cardiomyopathy
  • Congenital heart disease
  • Repaired tetralogy of Fallot
  • Ebstein's anomaly
  • Uhl's anomaly
  • Atrial septal defect
  • Partial anomalous venous return
  • Acquired heart disease
  • Tricuspid valve disease
  • Pulmonary hypertension
  • Right ventricular infarction
  • Bundle-branch re-entrant tachycardia
  • Miscellaneous
  • Pre-excited AV re-entry tachycardia
  • Idiopathic RVOT tachycardia

Treatment

Treatment options can vary by patient and may include anti-arrhythmogenic medication, implantable cardioverter defibrillators and catheter ablation.

Resources

  • NIH