Effect of electrical stimulation of the lower esophageal sphincter in gastroesophageal reflux disease patients refractory to proton pump inhibitors

Figure 1 Lower esophageal sphincter stimulation system. A: EndoStim^® wireless Programmer, Implantable Pulse Generator and Bipolar Stimulation Lead. Inset shows the two stimulation electrodes and the butterfly used for anchoring the electrode at the LES; B: Schematic of the EndoStim^® System Implant in a Patient: Electrode position and IPG implant location. Bipolar stitch electrodes are placed in the abdominal esophagus anteriorly in an inline configuration 1 cm apart. The lead is connected to the IPG that is implanted in the subcutaneous pocket in the anterior abdomen. IPG: Implantable pulse generator; LES: Lower esophageal sphincter.

Figure 2 Frequency of daytime and nighttime symptoms of (A) heartburn and (B) regurgitation at baseline and with lower esophageal sphincter - electrical stimulation therapy at 12 and 24 mo. Data are presented as median and interquartile range (IQR). Absence of median value or IQR bars indicate a value of zero for the listed variables. NS = Not significant, ^aP < 0.05, ^bP < 0.01, ^dP < 0.001. A: Percent days with Heartburn at baseline, 12- and 24-mo following LES-EST. There was a significant reduction in reported daytime and nighttime with heartburn at both time points compared to baseline, in both groups; B: Percent of days with Regurgitation at baseline, 12- and 24-mo following LES-EST. There was a marked reduction in reported daytime and nighttime with regurgitation at both time points compared to baseline, in the incomplete responder group and a marked reduction in these variables in the responder group. LES: Lower esophageal sphincter; EST: Electrical stimulation therapy.