An 8-year-old boy with a history of multiple neonatal laparotomies, including congenital diaphragmatic hernia repair and an open fundoplication, presented acutely with severe abdominal pain, distension, vomiting and shock. A large abnormal opacity in the left upper quadrant was visible on a plain abdominal radiograph. The patient was taken to the theatre for emergency laparotomy and was found to have a massively distended stomach, the fundus and body of which were necrotic. A subtotal gastrectomy was performed, sparing the viable tissue. The patient went on to make a full recovery. Acute massive gastric dilatation (AMGD) is a rare condition characterised by severe gastric distension. Gastric ischaemia results when intragastric pressure exceeds venous pressure, obstructing venous outflow. It is important to recognise AMGD as a severe complication of fundoplication due to closed-loop gastric obstruction. It should prompt consideration of an early laparotomy in cases where the diagnosis is suspected.