[The esophagus in Chagas' disease: physiologic, pharmacologic and clinical studies].

Intramural denervation confirmed anatomopathologically and by means of a pharmacological test is the main factor responsible for achalasia of the cardia and for the absence of peristalsis in the esophageal body in Chagas' disease. The resulting difficulty in transit and stasis cause the main symptoms and complications of megaesophagus. Among the recent phenomena observed in the physiopathology and pharmacology of megaesophagus by the manometric method, we may mention: delayed pharyngo-esophageal time, concomitance of peristalsis and aperistalsis and abnormal responses of the lower sphincter to caerulein, atropine, nifedipine and isosorbitol dinitrate. Gammascintillography was shown to be useful in the study of esophageal transit in megaesophagus by permitting the detection of unsuspected abnormalities, especially when deglution is done with the patient lying down, and by affording a dynamic and quantitative view of the changes in esophageal emptying.