Familial sick sinus syndrome with atrioventricular conduction disturbance

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Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice
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Published on: July 5, 2021

M Isobe1, T Oka, H Takenaka

  • 1First Department of Internal Medicine, Shinshu University, School of Medicine, Matsumoto, Japan.

Japanese Circulation Journal
|November 7, 1998
PubMed

Insights

A family presented with sick sinus syndrome, a condition affecting heart rhythm. Electrophysiological studies and pacemaker implantation revealed underlying myocardial disease in affected members.

Area of Science:

  • Cardiology
  • Genetics
  • Pathology

Background:

  • Sick sinus syndrome (SSS) is a group of abnormalities of the sinus node, the heart's natural pacemaker.
  • Familial clustering of SSS suggests a potential genetic component in its etiology.
  • Understanding the underlying pathology is crucial for effective management.

Observation:

  • A mother and her two daughters were diagnosed with sinus node dysfunction.
  • Electrophysiological studies in the daughters indicated abnormal atrioventricular conduction.
  • Endomyocardial biopsy in one daughter revealed myocyte disarrangement, degeneration, necrosis, and fibrosis.

Findings:

  • The family members presented with symptomatic sinus node dysfunction requiring pacemaker implantation.
  • Histopathological findings from endomyocardial biopsy suggest an underlying myocardial disease contributing to SSS.
  • Abnormal atrioventricular conduction was observed in the affected daughters.

Implications:

  • This case highlights a potential inherited form of sick sinus syndrome possibly linked to myocardial disease.
  • Early diagnosis and pacemaker implantation are vital for managing symptomatic SSS.
  • Further research into the genetic and pathological basis of familial SSS is warranted.

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