Background: Functional obstructive gastroparesis is an understudied subtype of gastroparesis with normal 3 cycle per minute gastric myoelectrical activity that responds to botulinum toxin A injection and balloon dilation of the pylorus.
Aims: To determine the effect of pyloroplasty on symptoms, weight, gastric emptying, and gastric myoelectrical activity in patients with gastroparesis and normal 3 cycle per minute gastric myoelectrical activity.
Methods: Ten patients (average age 36 years with gastroparesis and normal 3 cycle per minute gastric myoelectrical activity) who had at least two successful endoscopic pyloric therapies and then underwent pyloroplasty were identified. Electrogastrography with water load satiety test was performed to determine gastric myoelectrical activity. Gastric emptying was measured with 4-h scintigraphy.
Key results: Six months after pyloroplasty, nine of ten patients reported improved symptoms and weight increased an average of 6.4 lb (p = 0.04). The average percentage of meal retained at 4 h decreased from 47% before to 16% after pyloroplasty (p < 0.01) and normalized in six patients. After pyloroplasty, the percent distribution of gastric myoelectrical activity power in the 3 cycle per minute range decreased at each measured interval compared with pre-pyloroplasty (p < 0.01).
Conclusions: (1) Pyloroplasty in these patients with obstructive gastroparesis improved gastric emptying and decreased 3 cycle per minute gastric myoelectrical activity, consistent with relief of functional gastric outlet obstruction. (2) Pyloric neuromuscular dysfunction is a key factor in delayed emptying in patients with functional obstructive gastroparesis.
Keywords: Nausea; Obstructive gastroparesis; Pyloric dysfunction; Pyloroplasty.