BACKGROUND Myxedema coma is a rare, life-threatening condition caused by a severe form of hypothyroidism. The dangerously low levels of circulating thyroid hormone can lead to progressive mental status changes and numerous organ dysfunctions, including serious cardiac abnormalities. CASE REPORT We present a case of a 59-year-old woman who presented with altered mental status and fall who was originally thought to have a cerebrovascular accident but was later diagnosed with myxedema coma, after multiple cardiac arrests. It was discovered that the patient had not been taking any of her medications for the last several weeks, after her primary care provider retired from practice. Initial laboratory evaluation was significant for a TSH level of 159.419 mIU/L and an undetectable free T4 level. Complications of the myxedema coma resulted in QTC interval prolongation, causing torsades de pointes and sustained polymorphic ventricular tachycardia, requiring cardioversion. CONCLUSIONS This case demonstrates the importance of early detection and treatment of myxedema coma, as it can cause life-threatening cardiac arrhythmias. It also emphasizes the need to ensure proper medication adherence in patients with chronic medical conditions, as non-compliance can result in dire consequences.