[Myocardial infarction and shock associated with thyrotoxicosis]

A thyroid storm--a sudden, life-threatening exacerbation of thyrotoxicosis--can lead to multiple organ failure due to hyperactivity of the sympathetic nervous system. Symptoms may include fever, tachycardia, cardiovascular collapse, myocardial infarction, hepatic failure, cerebral infarction, delirium, coma, and rhabdomyolysis. Various therapies have been proposed for the management of thyrotoxicosis. They include: reduction of sympathetic outflow (beta-blockers); decreased production and release of thyroid hormone (thiamazole, propylthiouracyl, or iodine solution); and peripheral conversion of T4 to T3 (beta-blockers and steroids).

We present a case report of an atypical thyroid storm accompanied by multiple organ failure including coma, myocardial infarction, shock, respiratory failure and liver dysfunction. A 51-year-old female was admitted to the emergency department because of multiple organ failure. On admission the patient was unconscious, hypotensive, acidotic and hyperkalemic. Her core temperature was 37.6 degrees C, and she had an LVEF of 30%. Thyroid function tests showed thyrotoxicosis: the fT3 concentration was 17.3 pmol L(-1) (ref. range 2.3-6.3), fT4 50.4 pmol L(-1) (ref. range 10.3-24.4), and TSH 0.009 microU mL(-1) (ref. range 0.4-4.0). SGOT and SGPT concentrations were also increased. The electrocardiogram showed an elevated ST in leads II, III, aVF, and V2 to V5. Troponin I concentration was 5.1 ng mL(-1) (ref. range < 0.05). An emergency coronary angiogram revealed normal perfusion. Treatment was started with vigorous inotropic support(dopamine, dobutamine and norepinephrine, followed by intraaortic balloon counterpulsation. She also received thiamazole, beta-blockers, iodine solution, glucocorticoids and diuretics. On the 8th day, a subtotal thyroidectomy was performed. The patient was weaned from mechanical ventilation after 14 days and recovered without any neurological deficit.

The described case showed that a thyroid storm can present as multiple organ failure, requiring intraaortic balloon counterpulsation for the management of catecholamine-resistant shock.