Thyroid Storm Presenting as Acute Decompensated Biventricular Heart Failure in a Young Male

ABSTRACT

Introduction: Thyroid storm (TS) is a rare and life-threatening condition that carries an extremely high mortality rate up to 20% when treated and 100% if untreated. TS can have a variety of presentations, but it most commonly occurs with altered mentation, cardiovascular dysfunction, thermoregulatory dysfunction and at times gastrointestinal or hepatic dysfunction. TS can develop in patients who have long-standing untreated hyperthyroidism and is usually precipitated by an acute inciting event such as an infection, medication, or trauma. This is a case of TS that presented with atypical features in a young man. Early recognition of TS lead to successful treatment of his severe thyrotoxicosis and acute heart failure. Case Description A 32-year-old Haitian male with a history of ADHD, insomnia, and family history of cardiomyopathy, presented to the ED with 6-months of progressive shortness of breath, palpitations, and exertional chest pain following Covid-19 illness in his household, noting he was unable to donate blood due to tachycardia but was asked to return and donate plasma. In the last month he experienced intermittent symptoms of orthopnea, tremors, fevers, night sweats, diarrhea, anxiety, and severe fatigue for which his stimulant medication was increased to twice daily and for insomnia quetiapine dosage was increased. He works in landscaping and was unable to perform his usual labor duties due to progressive fatigue and dyspnea. Initial vital signs were temperature of 37.2ºC, sinus tachycardia at 130bpm, BP 118/73, tachypneic RR 21 with SpO2 99% on room air. On exam he had orthopnea, diaphoresis, scleral icterus, S3 gallop, bibasilar crackles, and hyperreflexia. He was admitted for acute decompensated heart failure with echocardiogram findings of ejection fraction 15-20% and grade 3 diastolic dysfunction with deep trabeculations as seen in noncompaction cardiomyopathy and BNP of 1200. Thyroid studies indicated thyrotoxicosis with undetectable TSH, high Free T4 (3.62 ng/dL), T3 (7.25 pg/ml), and high TSH receptor antibodies (5.08 IU/L). Covid-19 PCR was negative, and Lyme IgM was positive. His clinical condition was consistent with thyroid storm per Burch-Wartofsky Point Scale (BWPS). Using precise clinical criteria his score was 55;a score over 45 is highly suggestive of TS. He was managed with propylthiouracil (PTU), iodine, glucocorticoids, propranolol, and cholestyramine until Free T3 and Free T4 normalized. Discussion: Thyroid storm is important to recognize and diagnose in patients with symptoms of thyrotoxicosis. The etiology of this patient’s acute decompensated biventricular heart failure was thyroid storm with likely underlying familial cardiomyopathy, worsened by chronic undiagnosed hyperthyroidism, medication, COVID-19, or Lyme disease. The calculation of BWPS score, using precise clinical criteria, was essential in the recognition of thyroid storm. This patient significantly improved with the proper treatment protocol of TS due to Graves’ disease. In the era of the Covid-19 pandemic, this case can highlight a possible severe sequela of this viral illness including thyrotoxicosis and acute heart failure in a young patient.