Electrocardiograms Revealing Epsilon Waves Following Use of Hormone Supplements in Young Cardiac Arrest Patient.

introductionAn underlying cardiomyopathy should be suspected in young patients presenting with ventricular arrhythmias and sudden cardiac arrest. Electrocardiograms revealing epsilon waves are associated with many serious conditions such as arrhythmogenic right ventricular cardiomyopathy, posterior myocardial infarction, right ventricular infarction, infiltration disease, sarcoidosis, Brugada Syndrome, Tetralogy of Fallot, and hypothermia. This case report features epsilon waves in a young cardiac arrest patient suspected of having an unrecognized cardiomyopathy that resulted in a fatal arrhythmia in the setting of exogenous bovine thyroid hormone and steroid use.  Case presentation: A previously healthy 33-year-old male with a history of anabolic steroid use and bovine thyroid hormone use presented to the emergency department following witnessed cardiac arrest with bystander cardiopulmonary resuscitation (CPR). Upon emergency medical service (EMS) arrival, the patient was in ventricular fibrillation and received defibrillation with the return of spontaneous circulation. In the emergency department, he was unresponsive and required norepinephrine to maintain blood pressure. An epsilon wave and a prolonged QTc interval were noted on his electrocardiogram (ECG). CT angiogram of the chest and CT head were negative for acute abnormalities. Pertinent laboratory work-up included a lactate level of 12.0 mmol/L, thyroid-stimulating hormone of 0.02 ulU/L, and a free thyroxine level of 0.04 ng/dL. Cardiac ultrasound showed globally decreasedleft ventricular function with an ejection fraction of 25-30% and mild dilation of the right ventricle. A cardiac MRI was ordered but the patient had recurrent ventricular fibrillation and was too unstable to complete. He suffered anoxic brain injury with no improvements in neurologic function and was transitioned to comfort care. The patient died two months later in hospice care. The cause of cardiac arrest was attributed to the patient's steroid and bovine thyroid supplementation, but autopsy results revealed histologic evidence of possible arrhythmogenic right ventricular cardiomyopathy.  Discussion: Epsilon waves are widely known to be associated with structural abnormalities of the heart, most notably, arrhythmogenic right ventricular cardiomyopathies. Epsilon waves may be present in a variety of other medical conditions including posterior myocardial infarction, right ventricular infarction, infiltration disease, sarcoidosis, Brugada Syndrome, Tetralogy of Fallot, and hypothermia. This case report describes an epsilon wave found in a patient with suspected arrhythmogenic right ventricular cardiomyopathy that suffered a fatal arrhythmia triggered by bovine thyroid hormone and steroid use.