The first clinical implant of Linx device was performed a decade ago. Since then, all reported studies have consistently confirmed a high rate of symptom relief and discontinuation of PPI therapy, an objective reduction of esophageal acid exposure, and an improved quality of life.

The feasibility study included 44 patients implanted with the Linx at four study centers in USA and in Europe between February 2007 and October 2008. The short-term, mid-term, 4-year, and final results of this study have been previously published [6–9]. In the feasibility study patients served as their own control to assess the effect of treatment on esophageal acid exposure, symptoms, and use of proton pump inhibitors. The primary criteria for inclusion in the trial were age >18 and <85 years, typical reflux symptoms at least partially responsive to proton pump inhibitors, abnormal esophageal acid exposure, and normal contractile amplitude and wave form in the esophageal body. The primary criteria for exclusion were history of dysphagia, previous upper abdominal surgery, previous endoluminal antireflux procedures, sliding hiatal hernia >3 cm, esophagitis >grade A, and/or the presence of histologically documented Barrett’s esophagus . Patients with abnormal manometric findings (distal esophageal contraction amplitude of <35 mmHg on wet swallows or <70% propulsive peristaltic sequences) were also excluded. Preoperative evaluation consisted of symptom questionnaire and Gastro-Esophageal Reflux Disease-Health Related Quality of Life (GERD-HRQL) questionnaire, upper gastrointestinal endoscopy, barium swallow, standard esophageal manometry, and 24–48 h esophageal pH monitoring. All Linx devices were successfully implanted via a standard laparoscopic approach . The median operative time was 40 min. No intraoperative complications occurred. Patients were instructed to resume a regular diet after a chest film and radiological assessment of the esophageal transit were performed. All patients except one were discharged within 48 h. Thirty-three patients (75%) were followed at 5 years. The mean total GERD-HRQL score off PPI decreased from 25.7 at baseline to 2.9 at year 5 (p < 0.001), and 94% (31/33) patients had a >50% reduction in the total score compared to baseline; 91% of patients reported of being satisfied with their current condition. Esophageal pH testing was completed in 20 patients at 5 years: 85% of patients achieved either normal esophageal acid exposure or had at least a 50% reduction from baseline. Normalization of esophageal pH was achieved in 70% of patients. Complete cessation of drug therapy or a reduction of 50% or more of the daily dose at 5 years was achieved by 88% and 94% of patients, respectively. Forty-three percent of patients complained of mild dysphagia during the postoperative period which resolved by 3 months without treatment. Laparoscopic device explant was necessary because of persistent dysphagia in one patient, the need to undergo magnetic resonance imaging in another, and the persisting reflux symptoms in a third individual.

A randomized single-arm trial was performed in a cohort of 100 patients at 13 centers in the United States and one in the Netherlands [10]. The criteria of inclusion and perioperative subjective and objective evaluations were similar to the feasibility study. Significant improvements were seen in GERD related quality of life, regurgitation, and esophageal acid exposure. Use of PPI dropped to 13% at 3 years and patient satisfaction with reflux control increased to 94% after implantation. Importantly, these positive results were stable showing no degradation over the study time period. Although 14% of patients reported non severe bloating after implantation, all study patients retained their ability to belch and vomit. Dysphagia was present to some extent in 68% of patients but decreased to 4% by 3 years. Five percent of patients rated the dysphagia as severe and required endoscopic balloon dilation or surgical removal of device with complete resolution.

Two single-center studies have further validated the efficacy of the Linx procedure . In Milan, Italy, 100 consecutive patients underwent Linx implantation between 2007 and 2012. The median implant duration was 3 years, ranging from 378 days to 6 years. There was a significant reduction of acid exposure time and improvement of GERD-HRQL score, and freedom from daily dependence on PPI was achieved in 85% of the patients [11]. Another study from USA, including 66 patients with an average follow-up of 5.8 months, showed similar satisfactory results [12].

Three case-control studies found comparable control of reflux symptoms after surgical fundoplication or Linx implant up to 1 year follow up. However, the fundoplication group showed a higher rate of patients with inability to belch and vomit, along with more severe gas-bloat symptoms [13–15].

A safety profile analysis study of the first 1000 implants in 82 hospitals worldwide showed 1.3% hospital readmission rate, 5.6% need of postoperative endoscopic dilations, and 3.4% reoperation rate [16]. All reoperations were performed non-emergently for device removal. Among the 36 patients who had the device removed, the most commons symptoms were dysphagia and recurrence of reflux symptoms. In addition, 7% of patients enrolled in the randomized multicenter single-arm trial had the device removed due to persistent dysphagia in four, vomiting in one, chest pain in one, and reflux in one [17].

A single-center cohort study focused on reoperations for Linx removal and reported the long-term results of one-stage laparoscopic removal and fundoplication [18]. Eleven (6.7%) out of 164 patients who underwent a laparoscopic Linx implant with a median follow-up of 48 months were explanted at a later date. The main presenting symptom requiring device removal was recurrence of heartburn or regurgitation in 46%, dysphagia in 37%, and chest pain in 18%. In two patients (1.2%) full-thickness erosion of the esophageal wall with partial endoluminal penetration of the device occurred. Although the course of this complication appeared to be benign and easy to treat, it is possible that the long-term erosion rate of the Linx device will be higher than it has been reported so far. The median implant duration was 20 months, with 82% of the patients being explanted between 12 and 24 months after the implant. Device removal was combined with partial fundoplication, most commonly Toupet or Dor, in 11 patients and with reconstruction of the angle of His in one. There were no conversions to laparotomy and the postoperative course was uneventful in all patients. At the latest follow-up after reoperation (1–5 years), the GERD-HRQL score was within normal limits in all patients.