Case 2.
A 19-year-old gentleman with a history of smoking and marijuana use presented with left-sided chest pain, proceeded by intractable nausea and vomiting for two weeks. The pain radiated to the neck, upper back, and shoulders base and was not associated with shortness of breath. He did not report hematemesis or melena.  He denied upper respiratory tract symptoms. On presentation, his blood pressure was 162/91 mmHg, pulse rate of 82/min, temperature 36.7 °C (98.1 °F), and oxygen saturation of 98 % on ambient air. He had supraclavicular crepitus but otherwise normal systemic examination. CBC showed WBC count of 7.10 x 103 per microlitre., 13.8 g/dl, 214x103 per microlitre. EKG showed diffuse ST-segment elevation, PR segment depression, and evidence of left ventricular hypertrophy, with no reciprocal changes suggestive of acute pericarditis(Figure 1b).  Chest X-ray showed pneumomediastinum. A subsequent CT chest showed air in the anterior mediastinum, pneumopericardium, and subcutaneous emphysema (Figure 2b).Esophagram did not show any evidence of a leak. The patient was initially started on ibuprofen and colchicine given the EKG changes highly suggestive of acute pericarditis, but later therapy was tailored to mild analgesia with clinical observation. EKG changes subsided upon resolution of pneumo-pericardium.