What are the other Names for this Condition? (Also known as/Synonyms)

• Junctional Ectopic Tachycardia

What is His Bundle Tachycardia? (Definition/Background Information)

• His Bundle Tachycardia is a very rare congenital genetic tachyarrhythmia
• It is characterized by incessant tachycardia and high morbidity and mortality

(Source: His Bundle Tachycardia; Orphanet, National Institute of Health and Medical Research (INSERM), Paris.)

• The His bundle is a group of muscle cells in the heart
• These muscle cells play an important role in transmission of electrical impulses in the heart

Who gets His Bundle Tachycardia? (Age and Sex Distribution)

• His Bundle Tachycardia is a highly uncommon congenital disorder. The presentation of symptoms may occur at birth
• Both males and females may be affected

What are the Risk Factors for His Bundle Tachycardia? (Predisposing Factors)

• A positive family history may be an important risk factor, since His Bundle Tachycardia can be inherited
• Currently, no other risk factors have been clearly identified for this condition

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of His Bundle Tachycardia? (Etiology)

The genetic cause of His Bundle Tachycardia and the mode of inheritance are not known at the present time.

What are the Signs and Symptoms of His Bundle Tachycardia?

The signs and symptoms of His Bundle Tachycardia may include:

• Cardiomyopathy
• Junctional Ectopic Tachycardia
• Neoplasm of the heart

(Source: His Bundle Tachycardia; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

How is His Bundle Tachycardia Diagnosed?

His Bundle Tachycardia is diagnosed on the basis of the following information:

• Complete physical examination
• Thorough medical history evaluation
• Assessment of signs and symptoms
• Laboratory tests
• Electrocardiography to check electrical activity in the heart
• Imaging studies

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of His Bundle Tachycardia?

The complications of His Bundle Tachycardia may include:

• Arrhythmia
• Complete heart block due to aberrant electrical activity
• Cardiac arrest

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is His Bundle Tachycardia Treated?

There is no cure for His Bundle Tachycardia, since it is a genetic condition. The treatment is usually given to manage the signs and symptoms and any complication that develops. The treatment methods employed may include:

• Medication to reduce arrhythmia (such as amiodarone, sotalol, propafenone, flecainide, etc.)
• Radiofrequency ablation of the His bundle

How can His Bundle Tachycardia be Prevented?

Currently, His Bundle Tachycardia may not be preventable, since it is a genetic disorder in many cases and runs in families.

• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

What is the Prognosis of His Bundle Tachycardia? (Outcomes/Resolutions)

• The prognosis of His Bundle Tachycardia is dependent upon the severity of the signs and symptoms and associated complications, if any
• Typically, the prognosis may be assessed on a case-by-case basis. However, it is poor in a majority of cases
• Children with severe arrhythmia and complete heart block may succumb to the disorder 

Additional and Relevant Useful Information for His Bundle Tachycardia:

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/