Gastroesophageal reflux disease (GERD) is one of the most prevalent diseases that we meet in daily practice, and its prevalence continues to rise.1,2 If left untreated or improperly managed, GERD can lead to esophagitis, esophageal strictures, aspiration, pneumonia, vocal cold inflammation and subsequent hoarseness, pulmonary dysfunction, Barrett esophagus, and esophageal cancer.2 Proton pump inhibitors (PPIs) have been for many years the principal medical treatment of GERD, but unfortunately between 20% and 30% of patients with erosive esophagitis and up to 40% of patients with nonerosive GERD have no or limited response to PPIs, even when their dose is doubled.3 There is also the concern for potential adverse effects of long-term treatment with PPIs including Clostridium difficile infection, bone fractures, hypomagnesemia and higher incidence of chronic kidney disease in susceptible individuals.4–6
Surgical correction of GERD has been the main treatment for those patients with poor response to PPIs and documented reflux on pH-impedance analysis. Antireflux surgery (ARS) has demonstrated improvement in patient symptoms and correction of pulmonary dysfunction, and it may play a role in reducing the incidence of esophageal cancer in patients with GERD.7 The most common surgical approach today is the laparoscopic Nissen fundoplication, although some other approaches such as the Toupet and the transthoracic Belsey have been used. However, patients with refractory GERD may not accept surgical correction of their GERD because of the invasive nature of the procedure, the risk of complications, and the risk of adverse events, including dysphagia, gas bloating, and inability to belch.8 It is in these cases where endoscopic treatment of GERD may have an emerging role, with different modalities arising in recent years (Fig. 45-1).9
Endoscopic antireflux treatments.
Among the different endoscopic therapies shown in Fig. 45-1, most are focused on trying to increase resistance at the gastroesophageal junction (GEJ).
The Stretta system (Mederi Therapeutics, Norwalk, CT, USA) applies radiofrequency (RF) energy to the lower esophageal sphincter (LES) and the cardia. It uses a flexible needle balloon and four electrodes that are placed at the level of the GEJ to apply the energy. The probes reach the level of the submucosa, where the RF energy is applied. Up to 14 applications could be given by changing the balloon position in relation to the Z-line. The system delivers low-power (5 W) energy, ensuring high temperatures (>85 °C) in the muscularis and the mucosal (>50 °C) levels. Regular cold irrigation prevents any injury to the mucosa.
The working mechanisms of this procedure are not well elucidated. Those described include scarring and tightening of the LES secondary to the thermal injuries induced and hypertrophy of the muscularis.10,11