Thyrotoxicosis Mimicking ST Elevation Myocardial Infarction

Abstract

Hyperthyroidism is well known to be associated with cardiac disease. Delay in making the diagnosis and occurrence of complications are common and are associated with a worse outcome.A 54-year-old male, non-smoker, with no past medical history and no significant family history presented to our hospital with severe left sided chest pain, “crushing” in nature. Electrocardiogram showed ST-segment elevations in the inferior leads. Troponin I level was 0.32 ng/mL (normal range 0-0.05 ng/mL) on presentation. The patient underwent an emergent coronary angiography which showed no evidence of occlusive coronary artery disease. The patient’s symptoms and signs prompted a high suspicion of thyrotoxicosis which was subsequently confirmed by a low thyroid stimulating hormone and high free thyroxine levels. The patient was given Methimazole and atenolol and his symptoms resolved.Awareness of coronary vasospasm due to thyrotoxicosis should be raised in patients presenting with typical angina pectoris with subsequent normal coronary angiographic results. History and physical examination may suggest underlying hyperthyroidism, but the absence of typical findings does not rule out the diagnosis.

Storm and STEMI: a case report of unexpected cardiac complications of thyrotoxicosis

“…Coronary vasospasm should be suspected among patients presenting with signs and symptoms of acute MI in the setting of a hyperthyroid state, but with normal coronary arteries on angiography. 4 , 5 …”

“…Computed tomography (CT) coronary angiography ( Figure 2 ) 2 days after presentation demonstrated no evidence of coronary artery atherosclerosis or stenosis. Additionally, cine cardiac CT images of the heart showed normal left ventricular systolic function ( Supplementary material online , Videos S 2 –S 4 ). Aspirin, ticagrelor, and heparin were stopped at this time due to a low concern for type I MI.…”

Evaluation of left ventricular myocardial work in patients with hyperthyroidism with different heart rates with noninvasive pressure-strain loop based on two-dimensional speck tracking imaging

“…As a result of increased sympathetic nerve excitability, the heart rate increases rapidly, oxygen consumption of the myocardium increases further with tachycardia, and subsequently, myocardial strain, cardiac hypertrophy, or coronary artery spasm occurs. These factors can lead to myocardial movement maladjustment and LV local systolic function change (5,31,34).…”

ST-Segment Elevation in Conditions of Non-cardiovascular Origin Mimicking an Acute Myocardial Infarction: A Narrative Review

“…Fatal disorders such as acute myocardial infraction presentation might be present in patients suffering from thyrotoxicosis, as seen in one case report, in which the patient presented with elevated ST segments in leads II, III, and aVF, as well as pressure-like chest discomfort and an increased troponin level. Despite the apparent lack of substantial cardiac risk factors, the presentation suggested an acute myocardial infarction (MI) [ 69 ]. Cardiovascular events are 2.6 times more likely to occur [ 70 ].…”

“…Cardiovascular events are 2.6 times more likely to occur [ 70 ]. ST-segment elevation mimicking acute myocardial infarction in thyrotoxicosis is the most possible mechanism, which is believed to be caused by coronary vasospasm due to thyrotoxicosis presenting with typical angina [ 69 ]. Vasospastic angina caused by transient coronary vasospasm affects up to 20% of thyrotoxicosis patients but is difficult to detect [ 71 ].…”