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A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis
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Transient ST-segment elevation due to iatrogenic hyperthyroidism in a patient with normal coronary arteries

Cetìn Mustafa1, Uçar Ozgül, Güven Cetìn Zehra

  • 1Department of Cardiology, Atatürk Chest Disease and Chest Surgery Education and Research Hospital, Sanatoryum caddesi, Turkey. mdmustafacetin@yahoo.com

Internal Medicine (Tokyo, Japan)
|August 2, 2011
PubMed

Insights

Thyrotoxicosis from L-thyroxine overdose can induce coronary vasospasm, leading to acute myocardial ischemia. This case highlights the importance of monitoring thyroid hormone levels to prevent cardiac events.

Area of Science:

  • Cardiology
  • Endocrinology

Background:

  • Acute myocardial ischemia can manifest with ST-segment elevation.
  • Coronary vasospasm is a potential cause of myocardial ischemia, even with normal epicardial coronary arteries.

Observation:

  • A 53-year-old male presented with angina pectoris and ST-segment elevation, indicative of acute myocardial ischemia.
  • Symptoms resolved promptly with nitroglycerine, suggesting a vasospastic etiology.
  • Coronary angiography showed normal epicardial coronary arteries.

Findings:

  • The patient was found to be in a thyrotoxic state due to a recent increase in L-thyroxine dosage.
  • The clinical presentation and diagnostic findings strongly suggested L-thyroxine-induced coronary vasospasm.
  • Withholding L-thyroxine and initiating diltiazem treatment led to symptom resolution.

Implications:

  • This case highlights a rare but serious adverse effect of L-thyroxine over-replacement.
  • Clinicians should consider thyroid hormone levels in patients presenting with unexplained myocardial ischemia, especially those on L-thyroxine.
  • Thyroid hormone-induced coronary vasospasm is a reversible cause of acute myocardial ischemia.

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