Acute Myocardial Infarction as a Consequence of Hypocalcaemia and Hyperthyroidism in a Young Patient Long After Subtotal Thyroidectomy

[摘要] Aim: Long-standing hypocalcaemia can be complicated by congestive heart failure. However, acute myocardial infarction as a first complication of hyperthyroidism and severe hypocalcaemia due to delayed onset of postoperative hypoparathyroidism, in a previously normal young patient, long after subtotal thyroidectomy, has been rarely reported in the literature.Patient and Methods: We report the case of a 37 year old male urgently admitted to our department because of chest pain, ECG changes, andlaboratory findings of acute myocardial infarction. A previous history of subtotal thyroidectomy 17 years ago is reported. Since then he was totallyasymptomatic, reported no drug or alcohol abuse and except for mild smoking he had no other risk factors for coronary artery disease. Moreover,clinical examination revealed a positive Trousseau’s sign, while ECG also showed prolonged QT interval. Chest x-ray was normal. Laboratory analyses revealed severe hypocalcaemia in repeated measurements (Ca++: 5.86 mg/dl; normal: 8.2–10.7 mg/dl), hyperphosphataemia (Phos:6.06 mg/dl; normal: 2.4–4.9 mg/dl), low serum levels of PTH (5 pg/ml; normal: 10–55 pg/ml), while thyroid function tests revealed hyperthyroidism (hTSH: 0.005 IU/ml; normal: 0.27–4.2 IU/ml), FT3: 7 pg/ml (normal: 1.82–4.62 pg/ml). All the other haematological and bloodchemistry results were normal (normal renal function tests, normal albumin levels).Results: Except for thrombolysis and treatment of the acute myocardial infarction in the intensive care unit, supplementation with calcium andvitamin D3, as well as anti-thyroid drugs (carbimazole 15 mg 3 times daily) were initiated. Cardiac catheterisation, which followed, showedone-vessel disease (70 % stenosis of the proximal section of left anterior descending coronary artery), which was treated with angioplasty andstenting. Thereafter, the patient remained asymptomatic and is under continuous calcium and vitamin D3 supplementation and anti-thyroiddrugs.Conclusions: According to this case, we considered the acute myocardial infarction of this patient being a consequence of hyperthyroidism and severehypocalcaemia, due to delayed onset of postoperative hypoparathyroidism, in a previous asymptomatic patient, with minimal angiographic lesions and absence of other risk factors.

[学科分类] 心脏病和心血管学

[关键词] akuter Myokardinfarkt;Hyperthyreose;Hypokalzämie;Thyreoidektomie;acute myocardial infarction;cardiology;hyperthyroidism;hypocalcaemia;thyroidectomy