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A case of 'Masquerading' bundle branch block: a forgotten concept

Dinesh Choudhary1, Narayanan Namboodiri2, Jaganmohan A Tharakan3

  • 1Fellow in Cardiac Electrophysiology, Department of Cardiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology (SCTIMST), Thiruvananthapuram 695 011, India.

Indian Heart Journal
|March 4, 2014
PubMed

Insights

A rare congenital heart condition caused congestive heart failure and a unique ECG pattern known as masquerading bundle branch block. This case highlights a novel association between intranuclear inclusion myopathy and this specific cardiac presentation.

Area of Science:

  • Cardiology
  • Genetics
  • Pathology

Background:

  • Masquerading bundle branch block (MBBB) typically presents as right bundle branch block in precordial leads and left bundle branch block with left axis deviation in frontal leads.
  • MBBB is commonly associated with coronary artery disease and hypertension, but its etiology remains unclear.
  • Congenital heart conditions can manifest with complex electrocardiographic findings.

Observation:

  • This report details a rare case of congenital intranuclear inclusion myopathy.
  • The patient presented with congestive heart failure and an ECG showing MBBB.

Findings:

  • This case demonstrates an unusual association between congenital intranuclear inclusion myopathy and MBBB.
  • The findings suggest a potential link between this rare genetic disorder and cardiac electrical abnormalities.

Implications:

  • This case expands the known clinical spectrum of congenital intranuclear inclusion myopathy.
  • Further research may elucidate the mechanisms underlying MBBB in genetic myopathies and its implications for cardiovascular risk stratification.

Keywords:
Left axis deviationLeft bundle branch blockMyopathyRight bundle branch block‘Masquerading’ bundle branch block

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