MSFinals-5715

MSFinals-5715

A 35-year-old male patient presented to the Emergency department with sudden onset chest pain and shortness of breath that had been ongoing for six hours. The symptoms appeared out of nowhere while he was watching TV, and lying flat made the breathlessness worse. The patient denied any recent history of infection, cough, fever, leg pain, swelling, or travel.
Upon examination, the patient was apyrexial and showed no signs of cyanosis. Respiratory examination revealed reduced breath sounds and hyperresonance in the right lung.
What is the most likely diagnosis?