Cardiac wall motion abnormalities observed in a patient with transient hyperthyroidism

Area of Science:

• Cardiology
• Endocrinology
• Internal Medicine

Background:

• A 74-year-old female with hypertension and hyperlipidemia presented with cardiac symptoms.
• Electrocardiography revealed sinus tachycardia and ST-segment elevations, suggestive of acute cardiac injury.

Observation:

• Echocardiography showed left ventricular apical hypokinesis.
• Coronary angiography was normal, ruling out obstructive coronary artery disease.
• Blood tests indicated elevated cardiac enzymes (creatine kinase MB, troponin T) and transient hyperthyroidism markers (free triiodothyronine, free thyroxine, thyroid antibodies).
• Myocardial scintigraphy demonstrated impaired apical perfusion and fatty acid metabolism.

Findings:

• The patient's presentation mimicked myocardial infarction but was associated with subclinical hyperthyroidism.
• Normal coronary angiography in the presence of elevated cardiac markers and regional wall motion abnormalities points towards non-ischemic cardiomyopathy.
• The constellation of findings suggests a potential link between transient hyperthyroidism and cardiac dysfunction.

Implications:

• Mild, transient hyperthyroidism may act as a trigger for tako-tsubo cardiomyopathy or myocardial infarction.
• This case underscores the importance of evaluating thyroid function in patients presenting with acute cardiac syndromes, especially when coronary angiography is normal.
• Further research is warranted to elucidate the mechanisms linking thyroid dysfunction and cardiac events.