Summary Objectives Flexible endoscopic septum division is an established treatment for Zenker’s diverticulum (ZD); however, long-term outcome data are lacking. We aimed to evaluate the long-term efficacy of flexible endoscopic septal division (FESD) using the stag beetle knife for ZD and identify predictors of symptom recurrence. Methods Patients undergoing the procedure between 2013 and 2018 were prospectively enrolled. Procedures were performed by a single operator. Symptom severity pre- and postprocedure was recorded using the dysphagia, regurgitation, and complications scale. Symptom recurrence was defined as a total score > 1 after the index procedure. Time-to-event analyses were performed using Kaplan–Meier plots, with multivariable analyses performed using Cox regression models. Results Altogether, 65 patients (mean age 74.0 years, 60% male) were included. Previous stapling had been performed in 44.6% of patients. Over the mean posttreatment follow-up period of 19 months, 5.6% of the treatment naïve group and 34.5% of the recurrent group underwent repeated FESD (P = 0.003), with rates of symptom remission and improvement of 75.4% and 92.7%, respectively. Recurrence at 48 months was higher in patients with recurrent ZD (84.7%) than in treatment-naïve patients (10.7%). On multivariable analysis, recurrent disease (hazard ratio [HR] 20.8, P = 0.005) and younger age (HR 0.96/year, P = 0.047) were associated with symptom recurrence. Conclusions In patients with treatment-naïve ZD, flexible endoscopic septal division is safe and provides durable symptom remission. However, in patients with poststapling recurrence, the risk of recurrence is high and time-dependent.

Although barium swallow imaging is established in the investigation of Zenker's diverticulum (ZD), no agreed measurement protocol exists. We developed a protocol for measuring ZD dimensions and aimed to correlate measurements with symptoms and post-operative outcomes. This prospective study included patients with confirmed ZD who underwent flexible endoscopic septal division (FESD) between 2014 and 2018. ZD was confirmed on barium radiology with measurements reviewed by two consultant radiologists. Symptom severity pre-and post-FESD was measured using the Dysphagia, Regurgitation, Complications (DRC) scale. Regression analyses were conducted to identify dimensions associated with therapeutic success, defined as remission (DRC score ≤ 1) 6 months after index FESD. In total, 67 patients (mean age 74.3) were included. Interobserver reliability (intraclass correlation coefficients-ICCs) was greatest for pouch width (0.981) and pouch depth (0.934), but not oesophageal depth (0.018). Male gender (60.9%) was associated with larger pouch height (P = 0.008) and width (P = 0.004). A positive correlation was identified between baseline DRC score and pouch depth (ρ 0.326, P = 0.011), particularly the regurgitation subset score (ρ 0.330, P = 0.020). The index pouch depth was associated with FESD procedure time (rho 0.358, P = 0.041). Therapeutic success was achieved in 64.2% and was associated with shorter pouch height (median 14.5 mm vs. 19.0 mm, P = 0.030), pouch width (median 19.9 mm vs. 28.8 mm, P = 0.34) and cricopharyngeal length (median 20.2 mm vs. 26.3 mm, P = 0.036). ZD dimensions may be feasible and were evaluated using Barium radiology. Specific parameters appear to correlate with severity and post-FESD outcomes, which aid with pre-procedural planning.