A 17 year old high school senior presents to the Emergency Room with intermittent shortness of breath and lightheadedness unrelated to exertion. He has never lost conciousness. He is otherwise "healthy" and is new to the health care system. He denies any recent illness, fever, cough, or history of lung disease. He has no family history of heart disease or unexpected death. His physical examination is completely normal and are the usual cauldron of ER blood tests. An EKG is obtained and you are called to review the EKG because the ER staff is "concerned." The EKG is shown below:
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So, what's the diagnosis? If you're unsure, what other history, exam findings, test(s) would you order?
Finally, would you send him home or admit him?