Stretta: A Naive Approach to a Complex Problem
I read with great interest the recent study: “No evidence for efficacy of radiofrequency ablation for treatment of gastroesophageal reflux disease: a systematic review and meta-analysis” by Lipka et al. from the University of South Florida. The study included only randomized trials that measured the LES pressure and esophageal acid exposure. Only 4 trials in the literature satisfied these criteria. The results are quite interesting. LES pressure and acid control improved in two studies only. Quality of life improvement and ability to discontinue proton pump inhibitors were similar in the Stretta and control arms. Overall, Stretta procedure when compared with sham therapy did not show any significant benefit.
These results are no surprise to any reflux specialist who deals with acid reflux disease or GERD on a daily basis. Acid reflux is the result of a defective barrier between the esophagus and the stomach. This barrier is a complex anatomic structure that consists of the lower esophageal sphincter muscle, the diaphragmatic crura, and the angle of Hiss. The phrenoesophageal membrane holds all 3 structures together in a delicate balance. All four components function in synchrony with esophageal peristalsis and gastric contractions. The end result is a one-way movement of food into the stomach except when vomiting. Many acid reflux experts agree that GERD is a multifactorial problem. Stretta, on the other hand, is an endoscopic procedure during which radiofrequency energy is delivered to the lower esophageal sphincter. The end result is increased fibrosis in the muscle presumably leading to “better” lower esophageal sphincter function. Even if we assume that the lower esophageal sphincter muscle tone increases following Stretta, this is unlikely to translate into acid reflux resolution. Creating a distal esophageal stricture or a hypertonic sphincter does not seem to address the different components of the gastroesophageal junction (GEJ) area. Nissen fundoplication surgery, on the other hand, tackles a number of factors that contribute to reflux. A floppy and short Nissen wrap, the most reliable treatment for GERD, increases gastric emptying, increases lower esophageal resting pressure, moves the acid pocket away from the GEJ and reposition the diaphragmatic crura around the intra-abdominal esophagus. This is far more involved than distal esophageal narrowing. More research is needed to understand the effect of Nissen fundoplication on acid reflux resolution. However, we no longer assume that acid reflux is solely the result of lower esophageal sphincter muscle hypotonia or transient relaxation. As a result, and in light of our increased knowledge about acid reflux pathophysiology, Stretta and other endoscopic procedures that are currently on the market and that are FDA approved don’t make lot of sense to me. It is our ethical obligation to inform our patients about the limitations of these so called “no scar” procedures, and I highly commend the authors of this study for their work and critical thinking.