Temporary implantable nitinol device (TIND): a novel, minimally invasive treatment for relief of lower urinary tract symptoms (LUTS) related to benign prostatic hyperplasia (BPH): feasibility, safety and functional results at 1 year of follow-up

Objectives: To report the first clinical experience with a temporary implantable nitinol device (TIND; Medi-Tate(®) ) for the treatment of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH).

Patients and methods: In all, 32 patients with LUTS were enrolled in this prospective study, which was approved by our Institutional Ethics Committee. Inclusion criteria were: age >50 years, International Prostate Symptom Score (IPSS) of ≥10, maximum urinary flow rate (Qmax ) of ≤12 mL/s, and prostate volume of <60 mL. The TIND was implanted within the bladder neck and the prostatic urethra under light sedation, using a rigid cystoscope. The device was removed 5 days later in an outpatient setting. Demographics, perioperative results, complications (according to the Clavien system), functional results and quality of life (QoL) were evaluated. Follow-up assessments were made at 3 and 6 weeks, and 3, 6 and 12 months postoperatively. The Student's t-test, analysis of variance (anova), Kruskall-Wallis test, and simple and multiple linear regression models were used in the statistical analyses.

Results: The mean patient age was 69.4 years, the mean (standard deviation, sd) prostate volume was 29.5 (7.4) mL and the Qmax was 7.6 (2.2) mL/s. The median (interquartile range, IQR) IPSS was 19 (14-23) and QoL score was 3 (3-4). All the implantations were successful, with no intraoperative complications recorded. The mean operative time (sd) was 5.8 (2.5) min and the median (IQR) postoperative stay was 1 (1-2) day. All but one of the devices (96%) was removed 5 days at after implantation in an outpatient setting. Four complications (12.5%) were recorded, including urinary retention (one, 3.1%), transient incontinence due to device displacement (one, 3.1%), prostatic abscess (one, 3.1%), and urinary tract infection (one, 3.1%). Multiple regression analysis failed to identify any independent prognostic factor for complications. There were statistically significant differences in the IPSS, QoL score and Qmax when comparing pre- and postoperative results at every time point. After 12 months, the median (IQR) IPSS and QoL score were 9 (7-13) and 1 (1-2), respectively, and the mean (sd) Qmax was 12 (4.7) mL/s. The mean variations with respect to baseline conditions at the same time points were -45% for the IPSS and +67% for Qmax . At 12 months after surgery (last follow-up visit), no patients required medical therapy or surgical procedures for BPH.

Conclusion: TIND implantation is a feasible and safe minimally invasive option for the treatment of BPH-related LUTS. The functional results are encouraging and the treatment significantly improved patient QoL. Further studies are required to assess durability of TIND results and to optimise the indications of such a procedure.