I read with great interest the publication in the current issue Surgical Endoscopy by Lee Swanstrom titled “Laparoscopic pyloroplasty is a safe and effective first-line surgical therapy for refractory gastroparesis”. The study includes 177 patients collected from a prospective foregut surgery database. 133 of those patients (75%) underwent a concurrent fundoplication for GERD related issues. Gastroparesis was defined by abnormal gastric emptying study, endoscopic visualization of retained food in the stomach or clinical symptoms suspicious of vagal nerve injury following complex re-operative foregut surgery. Postoperatively only 70 patients (39%) underwent a gastric emptying study and two thirds of those patients had normalization of their emptying study results. The authors report that 11% of the pyloroplasy patients underwent further treatment for failure of symptoms to improve. They conclude that laparoscopic pyloroplasty is an effective first line treatment for gastroparesis. The use of pyloroplasty does not preclude future surgical treatments for delayed gastric emptying and most patients do not go on to require additional treatments for gastroparesis.
This study is misleading and should not have been published at all. There is no way to make any conclusions about pyloroplasty effect on gastrorparesis when the majority of patients 75% had a concurrent fundoplication. Indeed, gastric fundus surgery in the form of gastric sleeve or gastric bypass is the most effective treatment of delayed gastric emptying. In this series, the concomitant fundoplication must have had a considerable effect on gastric emptying improvement and this cannot be dismissed. Nissen fundoplication improves gastric emptying and causes dumping symptoms in certain cases.
Additional limitations are noted and further weaken this study. Less than half of the patients underwent postoperative gastric emptying testing to document improvement and the authors do not mention the number of patients who underwent preoperative testing. Relying on symptom analysis alone, especially in a patient population that suffers from GERD related symptoms, does not reliably demonstrate gastroparesis resolution. There are too many assumptions in this study and a number of unfounded conclusions. The role of pyloroplasty in treatment of gastroparesis remains limited and unsupported by studies and by logical reasoning. Gastroparesis pathophysiology is poorly understood. However, knowledge from bariatric surgery has allowed us to appreciate the function of gastric fundus in controlling gastric emptying. In our practice, gastric fundus resection rather than pyloroplasty is the first line surgical treatment of delayed gastric emptying. We have published a case of severe gastroparesis with dilated stomach and have shown that gastric volume reduction mainly at the level of gastric fundus improves gastric emptying. The pylorus does not control gastric motility. Rather gastric fundus and post-pyloric signals emanating from the proximal intestine control stomach motility and emptying.
In conclusion, gastric emptying remains a complex physiological process that is poorly understood. Gastric emptying is related to a number of medical problems like obesity and diabetes that have reached epidemic levels in our society. Understanding gastro-intestinal motility is crucial to advancing our treatment approach to gastroparesis, obesity, diabetes and acid reflux disease. Passive drainage procedures like gastro-jejunostomy and pyloroplasty have little impact on gastric emptying physiology. Please leave the pylorus alone and concentrate on understanding gastric fundus role in gastric motility.