Michael D Crowell, PhD, Leonardo Rodriguez, MD, Edy Soffer, MD
Mayo Clinic in Arizona, Surgery, CCO Obesidad Y Diabetes, University of Southern California
INTRODUCTION: Chronic electrical stimulation of the LES in patients with GERD, using EndoStim LES stimulation system (EndoStim BV, the Hague, Netherlands), has been shown to enhance LES pressure, decrease distal esophageal acid exposure and improve GERD symptoms.
AIM: To evaluate, in a post-hoc analysis, the effect of electrical stimulation of the LES on proximal esophageal acid exposure measured at 23cm above the manometric upper border of the LES.
METHODS: Nineteen patients (median age 54 yrs.; IQR 47-64; 10 men) with GERD at least partially responsive to PPIs, hiatal hernia < 3 cm, esophagitis < LA grade C underwent laparoscopic implantation of the LES stimulation system. Electrical stimulation at 20 Hz, 220usec, 5-8mAmp in 6-12, 30 minutes sessions was delivered starting on day 1 post-implant. Esophageal acid exposure at baseline and after 12-months of LES electrical stimulation therapy was measured using dual channel pH probe with pH sensors 5 and 23cm above the manometric upper border of LES.
RESULTS: Total, upright and supine values of median (IQR) proximal esophageal acid exposure at baseline were 0.4 (0.1-1.35), 0.6 (0.2-2.1) and 0 (0.0-0.15) %, respectively. The corresponding values for each of these variables after 12-months of LES electrical stimulation therapy were 0 (0-0) % (p=0.001 for total and upright and p=0.043 for supine comparisons). Distal esophageal pH improved from 10.2 (7.6-11.7) to 3.6 (1.5-7.5) % (p=0.001). Seven (37%) patients had abnormal proximal esophageal acid exposure of > 1.1% at baseline. All seven patients normalized their proximal esophageal acid exposure (p=0.008). In the 7 patients with abnormal proximal esophageal pH, total, upright and supine median proximal esophageal 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. The corresponding values after 12-months of LES electrical stimulation therapy were 0 (0-0.1), 0 (0-0.2) and 0 (0-0) % (p=0.018 for total and upright and p=0.043 for supine comparisons). Distal esophageal pH for this group improved from 9.3 (7.8-17.2) to 3.4 (1.1-3.7) % (p=.043). There were no GI side-effects of dysphagia, gas-bloat or diarrhea reported with electrical stimulation therapy. There were no device or procedure related serious adverse events.
CONCLUSION: Electrical stimulation therapy of the LES is associated with normalization of proximal esophageal acid exposure in patients with GERD and may be useful in treating proximal GERD. The LES electrical stimulation therapy is safe and not associated with GI side-effect seen with typical antireflux surgery.
Session: Podium Presentation
Program Number: S066