Abstract Introduction Thyroid storm is a rare, life-threatening complication of thyrotoxicosis, often precipitated by an acute stressor. Treatment typically includes Propranolol, Antithyroid drugs, and Steroids, which aim to counteract the adrenergic effects of excess thyroid hormone and inhibit peripheral conversion of T4 to T3. However, Propranolol may be detrimental in patients with unrecognized cardiac dysfunction, as illustrated in our case. Case Presentation A 30-year-old Native Hawaiian female with no significant past medical history presented to an outside ER after a syncopal episode, reporting a week of nausea, vomiting, diarrhea, and several weeks of weight loss. She was febrile, tachycardic, tachypneic, and mildly hypertensive. On exam, she had warm, clammy skin, a non-tender, normal-sized thyroid, and mild pedal edema. Labs were notable for leukocytosis, hyponatremia, hypokalemia, lactic acidosis, transaminitis, hyperbilirubinemia, TSH 0.01 µIU/mL and free T4 7 ng/dL. Imaging was consistent with mild tonsillitis and right-sided pyelonephritis. She was fluid resuscitated and started on empiric antibiotics. Based on a Burch-Wartofsky Point Scale score of 70,She was diagnosed with thyroid storm, and treatment was initiated with oral propranolol and propylthiouracil (PTU). During transfer to a tertiary center, she developed shock requiring vasopressors. Decision-Making High-dose IV hydrocortisone was promptly administered. An emergent echocardiogram revealed biventricular systolic dysfunction with an EF of 40-45% and grade I diastolic dysfunction. Given her hemodynamic instability, further beta-blockade was withheld. She eventually stabilized, and over the following days, steroids were tapered and PTU was transitioned to methimazole. Graves' disease was confirmed by thyroid ultrasound with a prominent, heterogeneous gland with increased color Doppler flow, and positive thyroid receptor antibodies. Her heart failure with reduced ejection fraction (HFrEF) was attributed to thyrotoxic cardiomyopathy (TCM) and was managed with guideline-directed medical therapy. Conclusion Thyrotoxicosis significantly impacts the cardiovascular system by increasing cardiac inotropy, chronotropy, diastolic filling, and cardiac output, while simultaneously reducing systemic vascular resistance. These effects initially lead to high-output heart failure. In young, healthy individuals, prolonged undiagnosed disease may lead to HFrEF - a rare, serious complication that is often overlooked. Although propranolol remains the preferred agent in thyroid storm, its use may precipitate circulatory collapse in patients with underlying or unrecognized cardiac dysfunction. Emerging literature suggests Esmolol, a short-acting, beta-1 selective agent, may offer a safer alternative in these cases when rate control is necessary. This case underscores the need for early cardiac imaging and individualized beta-blocker selection in suspected TCM to minimize hemodynamic compromise. This abstract is funded by: None
Al-Sammarraie et al. (Fri,) studied this question.