A 42-year-old man, who has been suffering from a duodenal ulcer for 20 years, has developed a constant feeling of heaviness in the stomach after eating. His eructation carries the smell of decay and vomiting occurs with the food eaten the day before. He has lost weight. His condition is relatively satisfactory, tissue turgor is reduced. The abdomen is soft on palpation, there are no signs of peritoneal irritation, and a «sloshing sound» can be heard in the epigastrium. Defecation occurs once in 3 days. What complication most likely corresponds with the patient’s condition and the described clinical presentation?