The clinical significance and natural history of the double pylorus. 
The double pylorus is a fistulous communication between the gastric antrum and duodenal bulb.  In most instances, it is believed to be a complication of peptic ulcer disease.  In prior reports, the longest follow-up has been only 5 years.  We report four cases of double pylorus, three of which have been followed medically (one for 7 years), and a fourth which required surgery for recurrent pain after 10 years of medical treatment.  In previously reported cases, only 20% have required surgery, usually for refractory symptoms, whereas 80% of patients have been managed medically and have been free of complications.  In one of our cases, the mucosal bridge separating the pylorus from the fistula perforated, with coalescence of the two channels into one large gastroduodenal passage.  There were no serious clinical symptoms or sequelae caused by this additional destruction of tissue.  We conclude that the double pylorus is a destructive but relatively benign complication of peptic ulcer disease.