Causes of Artificial Urinary Sphincter Failure and Strategies for Surgical Revision: Implications of Device Component Survival.

BACKGROUND: Up to 50% of patients receiving an artificial urinary sphincter (AUS) require surgical revision after initial placement. However, the literature is heterogeneous regarding the leading causes of AUS failure and appropriate surgical management.

OBJECTIVE: To inform a revision approach by tabulating the causes of AUS failure, assessing AUS component survival, and examining the single-component revision efficacy.

DESIGN, SETTING, AND PARTICIPANTS: We retrospectively reviewed 168 patients receiving AUS placements carried out by a single surgeon from 2008 to 2016 at a high-volume academic institution. The median follow-up from initial placement was 2.7 yr, with 37.5% experiencing recurrent incontinence. The cuff size ranged from 4.0 to 5.5cm, with median size of 4.5cm.

INTERVENTION: Patients without infection or erosion underwent systematic device interrogation and revision, starting with the pressure-regulating balloon (PRB) and then, if necessary, the urethral cuff. Device revision involved either PRB-only correction or cuff and PRB revision.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We used bootstrapped intervals to estimate the mean time to failure for individual AUS components. Kaplan-Meier estimates were used to compare survival for individual components and for revised devices by revision technique.

RESULTS AND LIMITATIONS: PRB malfunction most commonly caused device failure, while cuff or pump malfunction was rare. Among patients undergoing surgical revision, those with PRB-only correction had similar outcomes to those with more extensive device correction (cuff and PRB exchange; p=0.46). This study, while systematic and detailed, is limited by sample size, follow-up length, and its retrospective nature.

CONCLUSIONS: PRB malfunction most commonly caused AUS failure in our cohort. PRB-only correction may satisfactorily restore AUS function in select patients. Consequently, initial interrogation of the PRB may avoid a second incision and urethral exposure for many patients requiring AUS revision.

PATIENT SUMMARY: Artificial urinary sphincters remain prone to failure over time. In many instances, correcting only the pressure-regulating balloon may effectively restore device function, allowing for a less invasive revision.