Intraoperative air embolism originating from a pulmonary vein.

Air embolism entering the systemic arterial system originating from the pulmonary circuit itself is an extremely rare occurrence. We report the case of an 18-year-old female undergoing correction of an atrial septal defect, who had an air embolism that is believed to have originated from the right superior pulmonary vein. Although the exact mechanism of air entry remains a matter of speculation, several plausible hypotheses are proposed and discussed. Injury to a pulmonary vein may lead to air entry with migration to the left atrium and ultimately to systemic embolism.