Abstract:
Introduction
Effective treatment of gastro-esophageal reflux disease (GERD) can be achieved by direct modulation
of the lower esophageal sphincter (LES) pressure. Recently the possibility of LES tonus increasing by
the means of implantable electrical stimulator was described. Although this method is already used in
clinical practice, optimal parameters of LES electrical stimulation are still unknown.
Study Aims
To obtain clinical data regarding effects of different modes of electrical stimulation of LES tonus.
Methods
LES electrical stimulation using external pulse generator was assessed in 9 patients with severe
GERD and decreased LES tonus. These patients underwent standard laparoscopic antireflux intervention
with additional insertion of 2 temporary electrodes at the level of gastroesophageal junction. Three sets
of parameters were studied: 1) low- frequency, long pulse (375 ms pulses, 6 mA at 6 pulse/min); 2) highfrequency
stimulation (0.3 ms, 6 mA at 40 Hz); 3) high-frequency, high-amplitude (0.3 ms, 10 mA at 40 Hz,
5 min intervals). High resolution esophageal manometry was used to assess changes in LES tonus. Each
set of parameters was used in three patients. Duration of postoperative LES electrical stimulation session
was 20 min. Esophageal manometry data during the stimulation were compared with postoperative
baseline (20 min), poststimulation period (20 min) and with preoperative manometric values as well.
Results
The low-frequency, long pulse stimulation produces moderate increase in LES pressure, which
is maintained in poststimulation period. The second set of parameters (used in commercially available
implantable stimulators) generates moderate relaxation of LES during the stimulation period and
significant increase of sphincter tonus in the poststimulation period. Patients stimulated with the third
set of parameters did not demonstrated modification of LES tonus during the stimulation with moderate
increase of the LES pressured in poststimulation period.
Conclusions
Electrical stimulation of LES produces changes in its tonus. Modifications in LES pressure during
the stimulation and after the stimulation period depend on many factors, including frequency, pulse
amplitude, waveform and duration of the stimulation. Further clinical studies are necessary for selection
of optimal stimulation parameters, which can be applied in the treatment of GERD.
Description:
VII Latvian Gastroenterology Congress with International participation
“Gastroenterology in the world and Latvia: Science for practice”
5 December 2015, Rīga, Latvia
Catedra de chirurgie nr. 4, Facultatea de rezidențiat și secundariat clinic, Universitatea de Stat de Medicină și Farmacie „Nicolae Testemițanu" din Republica Moldova
Clinical Republican Hospital, Laboratory of minimally invasive surgery, Kishinau, Moldova, State University of Medicine and Pharmacy “Nicolae Testemitanu”
Department of Surgery, Kishinau, Moldova
Medical engineering company Labromed, Kishinau, Moldova