[Familial right bundle branch block and left axis deviation without cardiac disorders (author's transl)]

Area of Science:

• Cardiology
• Genetics
• Electrophysiology

Background:

• Familial occurrence of cardiac conduction system disturbances is documented but infrequently reported.
• Bifascicular bundle branch block (BABB) involves impaired electrical signal conduction in the heart's His-Purkinje system.
• Understanding the genetic and environmental factors influencing BABB is crucial for diagnosis and management.

Observation:

• Three members of a single family presented with bifascicular bundle branch block on electrocardiography.
• One affected individual had a history of rheumatic myocarditis.
• The other two individuals with BABB showed no overt signs of cardiac disorder.

Findings:

• The study identified a familial aggregation of bifascicular bundle branch block.
• The presence of rheumatic myocarditis in one member suggests potential contributing factors.
• The absence of cardiac symptoms in other affected members indicates variable clinical penetrance.

Implications:

• This case underscores the importance of considering genetic predisposition in bifascicular bundle branch block.
• Further research into the multifactorial etiology and pathogenesis of familial conduction disturbances is warranted.
• Prognostic assessment in familial bifascicular bundle branch block requires careful, individualized evaluation due to limited data.