The esophagus below the carina lies directly posterior to the left atrium. Prior to the days of echocardiography a lateral view barium swallow was used to diagnose left atrial enlargement. The mid-esophageal dissection in a trans-hiatal esophagectomy takes place in this space. The distal esophagus passes to the left toward the cardia of the stomach as the aorta moves toward the midline behind it. The esophagus is identified during abdominal exploration (if there is no NG tube in place) by feeling the aortic pulsation behind it.
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