Steven Van Dyke is a 36-year-old Caucasian male smoker who presents to the ED following the acute onset of nonradiating, nonreproducible chest tightness of >20 minutes duration, symptoms beginning while he was watching TV. He complains of associated palpitations, shortness of breath, choking sensation, dizziness, nausea, sweating, and “fear of having a heart attack.” He reports a 1-month history of similar episodes lasting 5-20 minutes, and now increasing in intensity over the past week. The first episode happened while exercising; subsequent episodes occurred during work-related meetings. This is the first episode occurring at rest outside of the work setting. PMH is significant only for childhood asthma; he denies any history of psychiatric disease. The patient’s father died 2 years ago at age 62 due to an MI. PE reveals an anxious-appearing young male with fidgeting of hands and legs. He is tachycardic and takes deep breaths between speaking in phrases. The cardiopulmonary and neurologic exams are otherwise normal. Primary Diagnosis: Panic Disorder: characterized by episodic, unexpected panic attacks that occur without a clear trigger (American Psychiatric Association, 2013). Attacks have a rapid onset of intense fear with at least four of the physical and psychological symptoms, such as palpitations, sweating, trembling/shaking, sensations of shortness of breath, feelings of choking, chest pain or discomfort, nausea, dizziness, or fear of losing control or dying (Locke, Kirst, & Shultz, 2015). The disorder is not caused by the physiological effects of a substance or undiagnosed medical condition. Acute Coronary Syndrome: symptoms of chest pain, referred chest pain, dyspnea, nausea, vomiting, light-headedness, and diaphoresis. Chest pain is commonly the first symptom that describes it as sudden, severe, heavy, and crushing sensation. Physical examination reveals an increase in heart rate and blood pressure, abnormal extra heart sounds, pulmonary findings of congestion, or peripheral vasoconstriction (Huether & McCance, 2012, p. 607). Typical angina is described as substernal pain, occurs on exertion, and is relieved with rest (Achar, Kundu, & Norcross, 2005). Chest pain that occurs suddenly at rest or in a young patient may suggest acute coronary vasospasm, which occurs in Prinzmetal’s angina or cocaine or methamphetamine use (Achar et al., 2005). Hyperthyroidism: Elevated thyroid hormone levels amplify catecholamines resulting in