Urodynamic after-contraction waves: a large observational study in an adult female population and correlation with bladder and ureter emptying functions in women.

Objective: To evaluate different patterns of after-contraction (A-C) waves detected during urodynamic evaluation in women.

Patients And Methods: 4,110 women were prospectively observed regarding the presence of A-C waves upon urodynamic evaluation. Intravenous pyelography and ultrasound were requested. Paired t test, χ(2) test, Wilcoxon's rank sum test and correlation analysis were performed with a 95% significance level.

Results: There were three distinguishing patterns of A-C: type I - detrusor contraction after the regular voiding phase, type II - detrusor contraction persisting after the flow rate had stopped, and type III - rebound of the detrusor contraction after the flow. A-C was observed in 13.9% of the women. Type I A-C wave patterns were present in 68 patients (11.8%), type II A-C wave patterns in 477 patients (83.2%), and type III A-C wave patterns in 28 patients (10.3%). Studies with intravenous pyelography and ultrasound very frequently showed bladder mucosa, muscle thickening or trabeculation. Secondary ureterectasis related to A-C waves was also observed. Additionally, watts factor, maximum flow rate, detrusor pressure and opening detrusor pressure were markedly elevated in patients with type III A-C, suggesting enhanced detrusor contraction in these A-C waves.

Conclusion: A-C waves are a real urodynamic entity with different patterns of presentation and with clinical and morphological alterations.