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Reversible complete heart block due to hypercalcaemia

Venkatakrishnan Ramakumar1, Shyam S Kothari2, Sandeep Seth1

  • 1Department of Cardiology, All India Institute of Medical Sciences, New Delhi, India.

BMJ Case Reports
|January 19, 2021
PubMed

Insights

Severe hypercalcemia, a condition of high calcium levels, can cause complete heart block. This heart rhythm issue resolved after correcting the calcium levels and removing a parathyroid adenoma.

Area of Science:

  • Cardiology
  • Endocrinology
  • Internal Medicine

Background:

  • Syncope can be caused by various cardiac arrhythmias.
  • Complete heart block is a serious cardiac condition requiring prompt diagnosis and management.

Observation:

  • A 65-year-old woman presented with syncope and ECG findings of complete heart block with a narrow QRS escape rhythm and normal QT interval.
  • Laboratory investigations revealed severe hypercalcemia and elevated parathormone levels.

Findings:

  • The patient's complete heart block resolved upon correction of severe hypercalcemia.
  • A parathyroid adenoma was identified as the cause of hypercalcemia.

Implications:

  • This case highlights that severe hypercalcemia can induce reversible complete heart block.
  • The absence of QT interval shortening in this case suggests a distinct mechanism compared to other causes of heart block.
  • Endocrine disorders, such as parathyroid adenomas, should be considered in the differential diagnosis of unexplained cardiac conduction abnormalities.

Keywords:
arrhythmiascalcium and bonecardiovascular medicinepacing and electrophysiology

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