Delayed diagnosis of dilated thyrotoxic cardiomyopathy with coexistent multifocal atrial tachycardia: a case report.

BACKGROUND: Thyroid storm (TS) is a rare but potentially life-threatening sequelae of untreated or undertreated hyperthyroidism. While TS frequently causes high-output heart failure, low-output heart failure related to dilated cardiomyopathy (DCM) is extremely rare. Tachycardia is a common clinical presentation of TS, and ß1-selective blockers are the first-line agents for treating TS-associated tachycardia. However, given that ß-blockers have negative chronotropic and negative inotropic effects, amiodarone may be safe and effective for the treatment of TS-induced tachyarrhythmia in patients with moderate to severe heart failure. While long-term amiodarone administration causes hypothyroidism, or less frequently, hyperthyroidism, little is known about the effects of short-term amiodarone administration on thyroid function. CASE PRESENTATION: A 31-year-old healthy woman presented with worsening dyspnoea. She was tachycardic with multifocal atrial tachycardia (MAT) of 184 beats/min, confirmed by electrocardiogram. Echocardiographic findings were consistent with DCM, with an ejection fraction of 20%. Thus, she was initially diagnosed with acute heart failure due to DCM with coexistent MAT. Tachycardia persisted despite cardioversion attempts and treatment with multiple anti-arrhythmic drugs. Consequently, she rapidly progressed to cardiogenic shock and respiratory decompensation, which required intubation and an intra-aortic balloon pump support. Moreover, the undiagnosed Graves' disease, lack of suspicion, and postponed analysis of thyroid function tests led to a delayed diagnosis of TS. Amiodarone, which was initiated for MAT, unexpectedly ameliorated thyrotoxicosis, resulting in a euthyroid state and the patient's significantly improved condition and cardiac function. She was discharged on day 40. Finally, she underwent total thyroidectomy; thyroid pathology was consisting with Graves' disease. Her postoperative course was uneventful. CONCLUSIONS: Herein, we describe a case of delayed diagnosis of dilated thyrotoxic cardiomyopathy with coexistent MAT. The patient required intensive care due to the catastrophic sequelae and was successfully treated with amiodarone. This is the first case report of TS-associated MAT and highlights the clinical importance of high suspicion of TS in de novo heart failure with any tachyarrhythmia or DCM of unknown etiology and the potential effects of short-term amiodarone administration in the treatment of TS.

A case of Cushing's syndrome due to bilateral cortisol-secreting adenomas with unilateral DHEAS oversecretion.

A 39-year-old Japanese woman presented with typical clinical symptoms of Cushing's syndrome, including amenorrhea and hirsutism, for 2 years. The results of her initial endocrine evaluation were consistent with ACTH-independent Cushing's syndrome due to bilateral adrenal masses (diameters of 3.1 cm and 2.4 cm on the left and right, respectively). Serum dehydroepiandrosterone levels were 6,901 ng/mL (normal range 230-2,660 ng/mL). Bilateral laparoscopic adrenalectomies were performed (left adrenalectomy first and right adrenalectomy 3 months later). Following the left adrenalectomy, the results of the endocrine evaluations were still consistent with a diagnosis of ACTH-independent Cushing's syndrome. Serum dehydroepiandrosterone sulphate levels, however, were below the normal range (143 ng/mL). Unexpectedly, the patient's menstruation resumed 2.5 months after the left adrenalectomy. Pathological examination of the resected glands showed bilateral adrenocortical adenomas, one on the left with a diameter of 3 cm, and two on the right with diameters of 0.7 cm and 1.3 cm. Immunohistochemical analysis revealed side chain cleavage, 17α-hydroxylase, 3ß-hydroxysteroid dehydrogenase, and 21-hydroxylase immunoreactivity in each adenoma. Dehydroepiandrosterone-sulfotransferase immunoreactivity was pronounced in the left adenoma, less pronounced in one of the right adenoma and weak in the other right adenoma. These results were consistent with clinical endocrine findings. Ours is the first case of a patient with bilateral cortisol-secreting adenomas with unilateral oversecretion of dehydroepiandrosterone sulphate. Resumption of menstruation after the correction of the dehydroepiandrosterone-sulphate excess, despite persistent cortisol excess, indicates the importance of adrenal androgens for the regulation of the menstrual cycle.