The outcome of fundoplication in patients with GERD based on abnormal impedance testing

The role of impedance testing in selecting patients for antireflux surgery is poorly understood. The aim of this study was to compare the outcomes of patients that underwent antireflux surgery for GERD based on an abnormal pH/abnormal impedance test versus a normal pH/abnormal impedance test.

Records of patients who had an abnormal off-medication impedance test (≥ 48 total reflux events) who underwent antireflux surgery were reviewed and divided into two groups: normal [pH-] or abnormal [pH+] esophageal acid exposure (DeMeester score > 14.7). Symptom resolution was compared: scale 1 (no resolution) to 5 (complete resolution).

Eighty-two patients met criteria: 44 [pH+] and 38 [pH-]. There were no differences in the demographics or indications for surgery. The frequencies of heartburn and regurgitation symptoms were significantly reduced by fundoplication in both groups. Complete resolution of heartburn was more common in the [pH+] group (90%) compared to the [pH-] group (67%) [p = 0.02]. Resolution of regurgitation was similar in both groups (90% in the [pH+] group vs 79% in the [pH-] group, p = 0.20). The mean dysphagia frequency score decreased for the [pH+] group, but increased in the [pH-] group. New-onset dysphagia was more common in [pH-] patients (23%) compared to [pH+] patients (5%), (p = 0.02). Continued use of PPI medications was significantly more likely in [pH-] group (42%) compared to the [pH+] group (21%). There was no difference in surgical satisfaction rates between groups.

Patients with abnormal impedance and increased esophageal acid exposure had significantly better symptom resolution, less dysphagia, and less frequent PPI use with antireflux surgery versus those with normal pH. These findings urge caution in the use of abnormal impedance values with normal esophageal acid exposure for the selection of patients for an antireflux operation.