Long-term results of electrical stimulation of the lower esophageal sphincter for treatment of proximal GERD

Abstract

Introduction: Electrical stimulation of the lower esophageal sphincter (LES) in gastroesophageal reflux disease (GERD) patients, using EndoStim® LES stimulation system (EndoStim BV, the Hague, Netherlands), enhances LES pressure, decrease distal esophageal acid exposure, improves symptoms, and eliminates the need in many patients for daily GERD medications. Aim: To evaluate, in a post hoc analysis, the effect of LES stimulation on proximal esophageal acid exposure in a subgroup of patients with abnormal proximal esophageal acid exposure. Methods: Nineteen patients (median age 54 years; IQR 47–64; men-10) with GERD partially responsive to proton pump inhibitors (PPI), hiatal hernia ≤3 cm, esophagitis ≤LA grade C underwent laparoscopic implantation of the LES stimulator. LES stimulation at 20 Hz, 215 μs, 5–8 m Amp sessions was delivered in 6–12, 30 min sessions each day. Esophageal pH at baseline and after 12-months of LES stimulation was measured 5 and 23 cm above the manometric upper border of LES. Results: Total, upright and supine values of median (IQR) proximal esophageal pH at baseline were 0.4 (0.1–1.4), 0.6 (0.2–2.3), and 0 (0.0–0.2) %, respectively, and at 12 months on LES-EST were 0 (0–0) % (p = 0.001 total and upright; p = 0.043 supine comparisons). 24-hour distal esophageal acid exposure improved from 10.2 (7.6–11.7) to 3.4 (1.6–7.0) % (p = 0.001). Seven (37 %) patients had abnormal (>1.1 %) 24-hour proximal acid exposure at baseline; all normalized at 12 months (p = 0.008). In these 7 patients, total, upright, and supine median proximal acid exposure values at baseline were 1.7 (1.3–4.1), 2.9 (1.9–3.7), and 0.3 (0–4.9) %, respectively, and after 12 months of LES-EST were 0 (0–0.0), 0 (0–0.1), and 0 (0–0) % (p = 0.018 total and upright; p = 0.043 supine comparisons). Distal esophageal pH for this group improved from 9.3 (7.8–17.2) at baseline to 3.2 (1.1–3.7) % at 12-months (p = 0.043). There were no GI side effects such as dysphagia, gas-bloat or diarrhea or device or procedure related serious adverse events with LES-EST. There was also a significant improvement in their GERD-HRQL scores. Conclusion: LES-EST is associated with normalization of proximal esophageal pH in patients with GERD and may be useful in treating those with proximal GERD. The LES-EST is safe without typical side effects associated with traditional antireflux surgery.