Progress in Implantable Gastric Stimulation: Summary of Results of the European Multi-Center Study

Obezite Tedavisinde Takılabilir Gastrik Uyarıcı: Avrupadaki Çok Merkezli Çalışmanın Sonuçları ve Özeti

Obesity is a global problem, effecting an estimated 300 million individuals worldwide and causing an enormous economic burden. A new bariatric procedure, gastric myoelectrical stimulation, has been developed. The Implantable Gastric Stimulator (IGS^®) induces satiety, while avoiding the morbidity and the mortality of the common restrictive, malabsorptive or combination restrictive/malabsorptive operations. The procedure does not alter the normal anatomy. The safety and efficacy of this from of therapy is being evaluated in the Laparoscopic Obesity Stimulation Survey (LOSS), a European prospective non-randomized clinical trial involving 69 patients in 5 countries (Italy, Austria, Germany, Belgium and Portugal).

Between January 2002 and December 2003, 69 patients (F7M 49/20) with mean age 41 years (18-65), underwent IGS implantation. Mean BMI was 41 (35-57), mean weight 115.0 kg (65-160), and mean excess weight (EW) 52 kg (13-89). The LOSS involved 11 investigator centers located in 5 European Countries. All subjects gave signed informed consent for the operation and to enter this prospective non-randomized study.

The device consists of a stimulation lead implanted in the gastric wall, connected to an electronic pulse-generator (Transcend IGS^®, Transneuronix Inc., Mt. Arlington, NJ, USA) which is implanted subcutaneously.

Percent excess weight loss (%EWL) was: 8.6±1.8 (standard error (SE) 0.9±1.2) at 1 month, 15.8±2.3 (SE 1.38±2.1) at 3 months, 17.8±2.6 (SE 1.98±2.3) at 6 months, 21.0±3.5 (SE 2.64±2.6) at 10 months, and 21.0±5.0 (SE 3.78±2.9) at 15 months.

There were 7 intra-operative gastric penetrations, observed by gastroscopy; in these cases, the electrode was withdrawn and repositioned in an adjacent of the pes anserinus area. One patient required a reoperation to remove a retained lead needle. There were no other immediate peri-operative complications. No lead dislodgement was seen on the first postoperative day abdominal X-ray, nor in the following months on the lead impedance test. One patient presented during the first postoperative month with pain at the abdominal stimulator site. This symptom was reduced with NSAIDs.

Conclusion; preliminary data of LOSS showed that IGS can be safely implanted laparoscopically. The operation was easier to perform than other bariatric procedures. Studies indicate minimal peri-effects have been observed from gastric stimulation therapy. LOSS is evaluating weight loss over time. If the weight loss is maintained, the IGS could be considered as the first choice operation in the treatment of morbid obesity. IGS is not indicated as a second choice procedure after restrictive or malabsorptive operations.

REFERENCES

1. De Luca M, Segato G, Busetto L, Favretti F, Aigner F, Weiss H, De Gheldere C, Gaggiotti G, Himpens J, Limao J, Scheyer M, Toppino M, L. Zurmeyer E, Bottani G, Penthaler H. Progress in Implantable Gastric Stimulation: Summary of Results of the European Multi-Center Study. Obes Surg 2004;14(1):S33-S39.