Pneumomediastinum and ST-Segment Elevation.

Although acute myocardial infarction is the most clinically significant cause of ST-segment elevation, other serious clinical conditions have been reported with this electrocardiographic abnormality. We report a patient with pneumomediastinum who presented with dyspnea and electrocardiographic changes mimicking ST-segment elevation myocardial infarction. Coronary angiography demonstrated no evidence of myocardial injury and the electrocardiographic abnormality promptly resolved with the resolution of the pneumomediastinum.