Chest Tightness with Cycling Turned Out To Be Pneumomediastinum

BACKGROUND Pneumomediastinum, or mediastinal emphysema, means air present inside the mediastinum. It usually presents with symptoms of chest pain and shortness of breath. Examination can be significant for crepitus along the neck area. There are many risk factors associated with pneumomediastinum, including asthma and COVID-19. Most cases of pneumomediastinum improve with conservative management, and surgery (mediastinotomy) is reserved for complicated cases with tension pneumomediastinum. CASE REPORT This is the case of a 23-year-old man who presented with chest tightness after 3.5 h of cycling. The patient did have a prior history of clinically stable asthma, with no recent exacerbation, and denied any other associative factors. Imaging was significant for pneumomediastinum. The patient was admitted for observation in the hospital and treated with supportive care, without any surgical intervention. The patient had appropriate improvement in his symptoms in 24 h. Repeat imaging showed improvement in the pneumomediastinum, and the patient was discharged to outpatient follow-up. CONCLUSIONS Our case presents a unique link between cycling and pneumomediastinum. Prolonged cycling may emerge as a risk factor for this complication. People with a previous history of pneumomediastinum should be careful to review other risk factors prior to planning long-distance bicycling. Physicians need to keep this differential diagnosis in mind when encountering a patient with similar symptoms so that a timely diagnosis is made.