Thyrotoxicosis-Induced Cardiomyopathy Complicated by Refractory Cardiogenic Shock Rescued by Extracorporeal Membrane Oxygenation

Thyrotoxic Cardiomyopathy Unveiled: Insights From a Compelling Case Report

Thyrotoxicosis is a clinical condition characterized by inappropriately elevated thyroid hormone levels in the bloodstream, leading to systemic effects on the body. In fact, the thyrotoxic state has tight regulatory control over the cardiovascular system through genomic and non-genomic mechanisms. This study highlights a rare presentation of thyrotoxic cardiomyopathy (TCM), which, to the best of our knowledge, is one of the very few case reports involving heart failure with preserved ejection fraction (HFpEF) and only atrial involvement, compared to the previous literature. A 37-year-old female presented to the outpatient clinic with abdominal distention and neglected signs and symptoms consistent with thyrotoxicosis for a year. Investigations revealed high N-terminal pro-b-type natriuretic peptide (NT-proBNP) levels of 1788 pg/mL. Cardiac MRI and trans-thoracic echocardiogram (TTE) revealed bilateral atrial dilatation, a left ventricular ejection fraction (LVEF) of 60%, and diastolic dysfunction. Additionally, severe free-flowing tricuspid and mitral valve regurgitation were observed, with no evidence of pericardial effusion or ventricular abnormalities. Therefore, a diagnosis of TCM was suspected and eventually confirmed by excluding other differential diagnoses. Besides a diffuse goiter on ultrasonography, the thyroid panel test revealed low thyroid-stimulating hormone (TSH) levels of <0.01 mIU/L, a free thyroxine T4 of >100 pmol/L, and positive anti-thyroid peroxidase (TPO) and TSH receptor antibodies. Accordingly, a team of endocrinologists, cardiologists, and internists managed the patient with anti-thyroid medications alongside symptomatic treatment. A few days later, she was discharged in good condition, and a follow-up visit was arranged with the endocrinology and cardiology clinics. It is crucial to maintain a high level of suspicion to detect and treat TCM promptly, and a multidisciplinary approach should ideally be employed. This is not only important for the prevention of but also reversing potentially life-threatening cardiovascular complications.

Effective Treatment of Acute Tricyclic Antidepressant Poisoning with Cardiogenic Shock and Severe Rhabdomyolysis Using ECMO and CytoSorb® Adsorber

BACKGROUND Tricyclic antidepressant (TCA) drugs are a common cause of fatal poisoning because of their cardiotoxic and arrhythmogenic effects. Classic supportive management includes sodium bicarbonate, gastrointestinal chelating agents, and vasopressors. Recently, intravenous lipid emulsion (supported by a low evidence level) has also been used. CASE REPORT We report the case of a 55-year-old woman admitted to our Intensive Care Unit (ICU) with acute imipramine self-poisoning. She arrived at the emergency department 7 hours after imipramine ingestion; she had severe rhabdomyolysis upon admission, with creatine phosphokinase levels at about 52 500 IU/L (normal, <200 IU/L). She quickly developed cardiogenic shock and malign arrhythmia requiring veno-arterial extra corporeal membrane oxygenation (VA-ECMO). Continuous renal replacement therapy (CRRT) with CytoSorb® (CytoSorbents, Monmouth Junction, New York, United Sates of America) was started 19 hours after admission. We performed serial blood measurements of imipramine and its active metabolite desipramine as well as viewing the levels on the CRRT-circuit monitor. Cardiac function improved and ECMO was explanted after 4 days. She also had severe acute respiratory distress syndrome, which resolved spontaneously. The neurologic outcome was favorable despite early myoclonus. The patient regained consciousness on the fifth day. Her clinical evolution was marked by acute ischemia of the lower left limb due to the arterial ECMO cannula. CONCLUSIONS These measurements document the efficacy of the CytoSorb® adsorber in removing a lipophilic drug from a patient's bloodstream. To our knowledge, this is the first published case of CytoSorb® extracorporeal blood purification therapy for acute TCA poisoning.

Thyrotoxicosis-Induced Cardiomyopathy With Systolic Dysfunction

Thyrotoxicosis-induced dilated cardiomyopathy is a rare but potentially life-threatening complication of thyrotoxicosis, with an incidence of <1%. This condition is characterized by a dilatation of the ventricular chamber and a decrease in cardiac contractility. Untreated, it can lead to irreversible changes in cardiac structure and function, including dilated ventricular chamber, a decrease in ejection fraction (EF), and an increased risk of atrial fibrillation. We present a case of a 39-year-old patient with a diagnosis of thyrotoxicosis-induced acute heart failure. A two-dimensional (2D) echocardiogram disclosed an ejection fraction of 36%, with diffuse mild dilation of the atria and ventricles with trace mitral and tricuspid regurgitation. The anti-thyroid-stimulating hormone (TSH) receptor was positive, and Grave's disease was diagnosed. The patient eventually returned to baseline functional status and could return to basic activities of daily living without limitations. The patient was encouraged to follow up with outpatient cardiology. Early diagnosis of cardiac involvement in patients with thyrotoxicosis is critical. Promptly delivered intensive treatment with the rapid achievement of euthyroid state can potentially reverse cardiac dysfunction and improve patient outcomes.