Abstract
Purpose
To define operator learning curve inflection points for prostatic artery embolization (PAE) and their impact on technical efficiency, clinical outcomes, and adverse events.
Materials and Methods
Between May 2013 and May 2021, 296 consecutive patients with moderate-to-severe lower urinary tract symptoms, urinary retention, or gross hematuria from benign prostatic hyperplasia underwent PAE by an interventional radiologist without prior PAE-specific experience. Operator learning curves plotted procedure time, fluoroscopy time, contrast volume, and embolic endpoint data against sequential procedure number. Multiple regression analysis evaluated for improvements in these parameters, with segmented linear regression to detect learning curve inflection points. Linear and logistic regression evaluated for learning curve impacts on 6-month clinical outcomes and 90-day adverse events.
Results
No baseline patient characteristic varied over the series apart from decreasing pre-procedural gland volume (P < 0.01). Multiple regression analysis demonstrated experience-dependent improvements in procedure time, fluoroscopy time, and contrast volume (P < 0.01), with corresponding learning curve inflection points at 76 (P < 0.01), 78 (P < 0.01), and 73 (P = 0.10) procedures. Embolic endpoints did not vary with experience (P > 0.05). Post-procedure reductions in International Prostate Symptom Score (21.5 ± 6.2 to 6.7 ± 4.7), Quality of Life score (4.5 ± 1.2 to 1.3 ± 1.2), post-void residual (190 ± 203 to 97 ± 148 mL), and gland volume (142 ± 97 to 76 ± 47 mL) were substantial (P < 0.01) but did not vary with experience (P > 0.05), nor did adverse event frequency/severity (P > 0.05).
Conclusion
Operator technical efficiency plateaued after 73–78 PAE procedures. Clinical improvements were substantial and adverse event frequency/severity low, and neither varied with experience. Operators without prior PAE-specific experience may perform PAE safely and effectively from the outset.
Level of Evidence
Level 2b, Cohort Study.
Similar content being viewed by others
Abbreviations
- PAE:
-
Prostatic artery embolization
- LUTS:
-
Lower urinary tract symptoms
- BPH:
-
Benign prostatic hyperplasia
- CCI:
-
Charlson comorbidity index
- BMI:
-
Body mass index
- IPSS:
-
International prostate symptom score
- QoL:
-
Quality of life score
- PGV:
-
Prostate gland volume
- PVR:
-
Post-void residual
References
DeMeritt JS, Elmasri FF, Esposito MP, et al. Relief of benign prostatic hyperplasia-related bladder outlet obstruction after trans-arterial polyvinyl alcohol prostate embolization. J Vasc Interv Radiol. 2020;11:767–70.
McWilliams JP, Bilhim TA, Carnevale FC, et al. society of interventional radiology multi-society consensus position statement on prostatic artery embolization for treatment of lower urinary tract symptoms attributed to benign prostatic hyperplasia: from the society of interventional radiology, the cardiovascular and interventional radiological society of europe, société française de radiologie, and the british society of interventional radiology. J Vasc Interv Radiol. 2019;30:627-637.e1.
National Institute for Health and Care Excellence. Prostate artery embolization for lower urinary tract symptoms caused by benign prostatic hyperplasia. BJU Int. 2018;122:11–12.
Gravas S, Cornu JN, Gacci M, et al. EAU guidelines on management of non-neurogenic male lower urinary tract symptoms (LUTS), incl. benign prostatic obstruction (BPO). Eur Assoc Urol. 2021;1–111.
Lerner LB, McVary KT, Barry MJ, et al. Management of lower urinary tract symptoms attributed to benign prostatic hyperplasia: AUA guideline part II—surgical evaluation and treatment. J Urol. 2021;206:818–26.
Hopper AN, Jamison MH, Lewis WG. Learning curves in surgical practice. Postgrad Med J. 2007;83:777–9.
Das R, Lucatelli P, Wang H, et al. Identifying the learning curve for uterine artery embolization in an interventional radiological training unit. Cardiovasc Interv Radiol. 2014;38:871–7.
Jakobsson H, Farmaki K, Sakinis A, et al. Adrenal venous sampling: the learning curve of a single interventionalist with 282 consecutive procedures. Diagn Interv Radiol. 2018;24:89–93.
Yarmohammadi H, Gonzalez-Aguirre AJ, Maybody M, et al. Evaluation of the effect of operator experience on outcome of hepatic artery embolization of hepatocellular carcinoma in a tertiary cancer center. Acad Radiol. 2018;25:856–60.
Iezzi R, Posa A, Merlino B, et al. Operator learning curve for transradial liver cancer embolization: implications for the initiation of a transradial access program. Diagn Interv Radiol. 2019;25:368–74.
Ayyagari R, Powell T, Staib L, et al. Prostatic artery embolization in non-index benign prostatic hyperplasia patients: single-center outcomes for urinary retention and gross prostatic hematuria. Urology. 2020;136:212–7.
Ayyagari R, Powell T, Staib L, et al. Prostatic artery embolization using 100–300μm trisacryl gelatin microspheres to treat lower urinary tract symptoms attributable to benign prostatic hyperplasia: a single-center outcomes analysis with medium-term follow-up. J Vasc Interv Radiol. 2020;31:99–107.
Ayyagari R, Powell T, Staib L, et al. Case-control comparison of conventional end-hole versus balloon-occlusion microcatheter prostatic artery embolization for treatment of symptomatic benign prostatic hyperplasia. J Vasc Interv Radiol. 2019;30:1459–70.
Powell T, Kellner D, Ayyagari R. Benign prostatic hyperplasia: clinical manifestations, imaging, and patient selection for prostate artery embolization. Tech Vasc Interv Radiol. 2020;23:100688.
Carnevale FC, Moreira AM, Antunes AA. The “perfected technique”: proximal embolization first, then embolize distal for benign prostatic hyperplasia. Cardiovasc Inter Radiol. 2014;37:1602–5.
Pisco JM, Bilhim T, Pinheiro LC, et al. Medium- and long-term outcome of prostate artery embolization for patients with benign prostatic hyperplasia: results in 630 patients. J Vasc Interv Radiol. 2016;27:1115–22.
Uflacker A, Haskal ZJ, Bilhim T, et al. Meta-analysis of prostatic artery embolization for benign prostatic hyperplasia. J Vasc Interv Radiol. 2016;27:1686-1697.e8.
Kurbatov D, Russo GI, Lepetukhin A, et al. Prostatic artery embolization for prostate volume greater than 80 cm3: results from a single-center prospective study. Urology. 2014;84:400–4.
Dindo D, Demartines N, Clavien PA. Classification of surgical complications: a new proposal with evaluation in a cohort of 6336 patients and results of a survey. Ann Surg. 2004;240:205–13.
Moreira AM, Moreira de Assis A, Carnevale FC, et al. A review of adverse events related to prostatic artery embolization for treatment of bladder outlet obstruction due to BPH. Cardiovasc Interv Radiol. 2017;40:1490–500.
Muggeo V. Estimating regression models with unknown breakpoints. Stat Med. 2003;22:3055–71.
Xiong W, Sun M, Ran Q, et al. Learning curve for bipolar transurethral enucleation and resection of the prostate in saline for symptomatic benign prostatic hyperplasia: experience in the first 100 consecutive patients. Urol Int. 2013;90:68–74.
Kim KH, Yang HJ, Heo NH, et al. Comparison study of learning curve using cumulative sum analysis between holmium laser enucleation of the prostate and transurethral resection of the prostate: is holmium laser enucleation of the prostate a difficult procedure for beginner urologists? J Endourol. 2021;35:159–64.
Agreda Castañeda F, Buisan Rueda Ó, Areal Calama JJ. Análisis de las complicaciones en el aprendizaje del HoLEP: revisión sistemática. Actas Urol Esp. 2020;44:1–8.
Bilhim T, Costa N, Torres D, et al. Randomized clinical trial of balloon occlusion versus conventional microcatheter prostatic artery embolization for benign prostatic hyperplasia. J Vasc Interv Radiol. 2019;30:1798–806.
Kampantais S, Dimopoulos P, Tasleem A, et al. Assessing the learning curve of holmium laser enucleation of prostate (HoLEP). Syst Rev Urol. 2018;120:9–22.
Bilhim T, Vasco Costa N, Torres D, Campos Pinheiro L, Spaepen E. Long-term outcome of prostatic artery embolization for patients with benign prostatic hyperplasia: single-centre retrospective study in 1072 patients over a 10-year period. Cardiovasc Interv Rad. 2022;45(9):1324–36.
Funding
This study was not supported by any funding.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interests
Dr. Bhatia receives grants and personal fees from Merit Medical Incorporated, personal fees from Terumo Incorporated, personal fees from Mentice, grants and personal fees from Siemens Medical, stock holdings with Embolx Incorporated, and personal fees from Medtronic, outside the submitted work. All other authors have no conflicts of interest.
Consent for Publication
For this type of study consent for publication is not required.
Ethical Approval
For this type of study formal consent is not required.
Informed Consent
This study has obtained IRB approval from Yale University School of Medicine and the need for informed consent was waived.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Powell, T., Rahman, S., Staib, L. et al. Operator Learning Curve for Prostatic Artery Embolization and Its Impact on Outcomes in 296 Patients. Cardiovasc Intervent Radiol 46, 229–237 (2023). https://doi.org/10.1007/s00270-022-03321-w
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00270-022-03321-w