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Refractory adenosine-sensitive congenital His bundle tachycardia: response to calcium-channel blockers

K Sharada1, C Narasimhan, K Nageshwar Rao

  • 1Care Hospital, The Institute of Medical Sciences, Nampally, Hyderabad.

Indian Heart Journal
|October 17, 2003
PubMed

Insights

Congenital His bundle tachycardia is a rare pediatric arrhythmia. Calcium-channel blockers are effective when other drugs fail, offering a new treatment avenue for this condition.

Area of Science:

  • Pediatric Cardiology
  • Electrophysiology
  • Arrhythmology

Background:

  • Congenital His bundle tachycardia is a rare pediatric arrhythmia.
  • Tachycardiomyopathy can result from incessant arrhythmias in children.

Observation:

  • A 7-year-old child presented with tachycardiomyopathy due to incessant His bundle tachycardia detected in infancy.
  • The arrhythmia was resistant to amiodarone and beta-blockers.

Findings:

  • Electrophysiologic study showed conversion to sinus rhythm with intravenous adenosine and diltiazem.
  • The child maintained sinus rhythm on oral verapamil.

Implications:

  • Calcium-channel blockers represent a viable treatment option for congenital His bundle tachycardia.
  • This finding is significant as the arrhythmia often proves resistant to multiple antiarrhythmic drugs.

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