Artificial Urinary Sphincter Mechanical Failures—Is it Better to Replace the Entire Device or Just the Malfunctioning Component?

Abstract

We evaluate the characteristics of artificial urinary sphincter mechanical failures and compare outcomes based on the surgical revision strategy, replacing only the failed component or the entire device. A total of 1,802 male patients with stress urinary incontinence underwent artificial urinary sphincter procedures from 1983 to 2011 at our institution, of which 1,082 were primary placements. Of these patients 125experienced mechanical device malfunction. Multiple clinical and surgical variables were evaluated for a potential association with device malfunction. In addition, we evaluated for predictors of failure of the revised device, including time from primary artificial urinary sphincter to revision surgery and surgical revision strategy (single component vs entire device), with failure defined as any tertiary surgery. At a median followup of 4.2 years (IQR 0.8, 7.9) 125 patients experienced device malfunction. The urethral cuff was the most common component failure (46.1%), followed by abdominal reservoir (22.6%), tubing (21.7%) and pump (9.6%). There was no association of time from primary surgery to revision for mechanical failure (HR 0.89, p=0.33) or revision strategy (HR 0.47, p=0.15) withthe risk of tertiary surgery. Additionally, as there was no significant interaction between these variables (HR 1.11, p=0.39), no cutoff could be identified at which one revision technique produced significantly improved device survival compared to another. However, there was a trend toward improved 3-year device survival after replacement of the entire device vs a single component (76% vs 60%, p=0.11). No cutoff in time to mechanical failure could be identified to guidedecision making in the management of mechanical artificial urinary sphincter failure. Likewise, it is unclear if replacing the entire device, rather than the single malfunctioning component, alters device survival. As such, further studies are needed. However, given the current trend toward improved overall device survival, the limited additional risk and the lack of adequate clinical predictors fortertiary surgery, we would advocate for replacement of the entire device whenpossible.