IMPROVING THE DIAGNOSTIC YIELD OF HIGH-RESOLUTION ESOPHAGEAL MANOMETRY FOR GERD: THE "STRAIGHT LEG-RAISE" INTERNATIONAL STUDY.

BACKGROUND

/aims. The straight leg raise (SLR) maneuver during high resolution manometry (HRM) can assess esophagogastric junction (EGJ) barrier function by measuring changes in intra-esophageal pressure (IEP) when intra-abdominal pressure (IAP) is increased. We aimed to determine whether increased esophageal pressure during SLR predicts pathological esophageal acid exposure time (AET).

METHODS

Adult patients with persistent gastro-esophageal reflux disease (GERD) symptoms undergoing HRM and pH-impedance or wireless pH study off-PPI were prospectively studied between July 2021 and March 2022. After HRM Chicago 4.0 protocol, patients were requested to elevate one leg at 45 degrees for 5 seconds while supine. The SLR maneuver was considered effective when IAP increased by 50%. Intra-esophageal pressures were recorded 5 cm above the lower esophageal sphincter at baseline and during SLR. GERD was defined as AET >6%.

RESULTS

The SLR was effective in 295 patients (81%), 115 (39%) of whom had AET >6%. Hiatal hernia (EGJ type 2-3) was seen in 135 (46%) patients. Compared to patients with AET <6%, peak IEP during SLR was significantly higher in the GERD group (29.7 vs. 13.9 mmHg, p<0.001). Using receiver operating characteristic (ROC) analysis, an increase of 11 mmHg of peak IEP from baseline during SLR was the optimal cut-off to predict AET >6% (AUC 0.84, sensitivity 79%, specificity 85%), regardless of the presence of hiatal hernia. On multivariable analysis, IEP pressure increase during SLR maneuver, EGJ-CI, EGJ subtype 2, and EGJ subtype 3 were found to be significant predictors of AET>6% CONCLUSIONS: The SLR maneuver can predict abnormal AET, thereby increasing the diagnostic value of HRM when GERD is suspected.