Case Presentation: A 47-year-old Hispanic female smoker presented with aone-week history of severe, intermittent substernal chest pain radiating tothe left arm. The pain was associated with palpitations and shortness ofbreath. She was afebrile with a heart rate of 100, a blood pressure of119/59, a fine tremor, and brisk reflexes. No lid lag or proptosis wasappreciated. The thyroid was enlarged, non-tender, without palpablenodules. ECG showed T- Wave Inversions in leads V1-V2 and STdepressions in V4-V5. Chest pain was relieved by SL nitroglycerin.Lab results showed a peak Troponin of 0.20 (N < 0.06), TSH 0.01 mU/L (N> 0.45mU/L), free T4 5.54 (N < 1.46 ng/dl), total T3 4.50 pg/mL (N < 1.37ng/mL), free T3 21.0 ng/mL (N < 4.4 pg/ml), TSI 3.61 IU/L (N < 0.55 IU/L),thyrotropin R Ab 7.47 IU/L (N < 1.75 IU/L) and thyroglobulin Ab 1.3 IU/ml(ULN < 0.9 IU/ml). Thyroid US showed a heterogeneous enlarged thyroidgland with increased vascularity.For her NSTEMI she was treated with a heparin drip, aspirin, Clopidogrel,atorvastatin, propranolol, and isosorbide mononitrate. Methimazole wasstarted to treat thyrotoxicosis. Cardiac catheterization revealed coronaryvasospasm without evidence of valvular or coronary artery disease.Methimazole restored euthyroidism and she has not had recurrence ofangina.
Discussion: Rarely, hyperthyroidism can present with transient myocardialischemia secondary to coronary artery vasospasm in patients with normalcoronary arteries. The etiopathogenesis is unclear and may relate to adirect metabolic effect of excess thyroid hormone on the myocardium. In aKorean study evaluating chest pain in patients who underwent coronaryangiography, the incidence of coronary vasospasm was 5%, occurringmost frequently in women under 50 years of age with thyrotoxicosis [2].
Conclusions: Patients who present with angina and are thyrotoxic shouldbe evaluated for vasospasm. Females under 50 years old with Graves’disease are at highest risk. Treatment includes antithyroid medicationsalong with nitroglycerin, and we can consider calcium channel blockersincluding diltiazem. Treatment of thyrotoxicosis eliminates recurrence ofvasospasm [3].