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Unresolved Complete Heart Block in a Patient Treated for Euthyroid Graves' Disease: A Diagnostic Dilemma

Tharun Adithya Natesan1, Mehereen Murshed2, Sandhya Abraham3

  • 1Internal Medicine, Nottingham University Hospital NHS Trust, Nottingham, GBR.

Cureus
|January 15, 2025
PubMed

Insights

Thyroid disease significantly impacts cardiovascular health. This case highlights a rare instance of complete heart block in a teenager with hyperthyroidism due to Graves

Area of Science:

  • Cardiology
  • Endocrinology

Background:

  • Thyroid hormone (TH) significantly influences cardiovascular function, affecting contractility, oxygen consumption, cardiac output, blood pressure, and vascular resistance.
  • Both hyperthyroidism and hypothyroidism can lead to cardiac changes, but bradyarrhythmias like atrioventricular block are exceptionally rare in hyperthyroid states.

Observation:

  • A 16-year-old female presented with thyrotoxicosis.
  • She was incidentally diagnosed with asymptomatic complete heart block (CHB).
  • The CHB was discovered in the context of newly diagnosed Graves' disease.

Findings:

  • Complete heart block (CHB) is an exceedingly rare cardiac complication of hyperthyroidism.
  • The association between hyperthyroidism and CHB is infrequently reported, often linked to inflammatory conditions, infections, or medications.

Implications:

  • This case underscores the importance of considering rare cardiac manifestations in endocrine disorders.
  • Further investigation into the mechanisms linking Graves' disease and CHB may be warranted.
  • Highlights the need for comprehensive cardiac evaluation in patients with thyrotoxicosis.

Keywords:
bradyarrhythmiascomplete heart blockgraves' diseasehyperthyroidpermanent pacemaker (ppm)

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