Wide complex tachycardia

Dr. David Brown: Today’s case is that of a 19-yearold man who presented to the Emergency Department complaining of palpitations. He was at a party when he became aware of his heart pounding. There was no chest pain, dyspnea, or syncope. He felt lightheaded but denied vertigo, visual changes, or focal weakness or numbness. He had no significant past medical history and had never felt palpitations before. He did not receive regular medical care. He smoked a pack of cigarettes daily and frequently used marijuana, alcohol, and cocaine. He denied any drug use, however, on the evening of presentation. Are there any questions about the history? Dr. Laura Bontempo: Did the patient have any fever or other recent illness? Dr. Eric Legome: Was he taking any medications? Dr. Brown: He reported several days of congestion and sore throat without any fever or cough. He was taking no medications except for an unidentified overthe-counter cold medicine preparation. Dr. J. Tobias Nagurney: If this is a dysrhythmia, there may be underlying familial heart disease. Was there any family history of cardiac problems, specifically dysrhythmias, syncope, or sudden death? Dr. Brown: The patient reported no family history of cardiovascular disease or sudden death. On physical examination, he was an anxious young man with the odor of alcohol on his breath. Vital signs revealed a temperature of 37.2°C (97.9°F), blood pressure of 118/70 mm Hg, pulse of 160 beats/min, respirations of 16 breaths/ min, and an oxygen saturation of 100% on room air. The head was atraumatic. The pupils were 5 mm bilaterally and reactive to light. The oropharynx was clear. The neck examination revealed equal carotid pulses and no jugular venous distention or thyromegaly. The chest was clear to auscultation. The left ventricular apical impulse was nondisplaced. The heart sounds were crisp with a tachycardic S1 and S2. There were no murmurs or gallops. The abdomen was flat, soft, and nontender; there were no masses, organomegaly, or bruits. Bowel sounds were present. Rectal examination revealed no masses and brown stool that was negative for occult blood. The extremities had full pulses with no cyanosis or edema. The skin was warm and dry without rashes. Neurologic examination revealed an anxious man with rapid speech and an otherwise clear mental status. Strength and sensation were normal; gait was not tested. Are there any questions about the physical examination? Dr. Theodore Benzer: Were there any track marks on the skin to suggest injection drug use? Dr. Brown: There were no needle marks on the skin noted. Are there any thoughts regarding the initial presentation or management of this patient? Dr. Eric Nadel: This is a stable tachycardia in a young man with a history of drug use who is also taking cold medicine that likely contains a sympathomimetic agent. His pupils are somewhat dilated and he is anxious and speaking rapidly. I am most concerned with a dysrhythmia because of cocaine or sympathomimetic drug intoxication. While you were performing your initial history and physical examination, the patient was undoubtedly placed on a cardiac monitor. What did this show? Dr. Brown: The monitor showed a wide complex