A 71-Year-Old Man With Gas Accumulation in the Left Atrium.

A 71-year-old man with a history of atrial fibrillation presented to the emergency department with sudden unconsciousness after finishing lunch. Just 4 weeks ago, the patient underwent radiofrequency ablation for atrial fibrillation and regularly took rivaroxaban for anticoagulant therapy. According to the medical history, the patient suffered recurrent chest tightness and heartburn after radiofrequency ablation without other discomforts. During transportation to the hospital, the patient experienced a drop in BP after forceful vomiting.