Progressive cardiac conduction defect and cardiomyopathy in siblings with syncope

Area of Science:

• Cardiology
• Genetics
• Pediatrics

Background:

• Syncope in children can indicate serious underlying cardiac conditions.
• Left bundle-branch block (LBBB) is a significant finding requiring thorough investigation.

Observation:

• Three siblings presented with syncope and were diagnosed with LBBB.
• All three siblings experienced progression to complete heart block.
• Echocardiography revealed cardiomyopathy despite normal heart size on X-ray.

Findings:

• Pacemaker implantation successfully eliminated syncopal episodes in all affected siblings.
• The family study did not reveal other members with conduction defects.
• These cases suggest a novel form of familial cardiomyopathy.

Implications:

• This familial cardiomyopathy predominantly affects the cardiac conduction system.
• Early diagnosis and intervention, such as pacemaker implantation, are crucial.
• Further research into the genetic basis of this condition is warranted.