Combating Steal: Percutaneous Interventions for Dialysis Access Steal Syndrome

Percutaneous Management of Dialysis Access Steal Syndrome: Interventions and Outcomes from a Single Institution’s 20-Year Experience

Clinical question

To evaluate the outcomes of percutaneous interventions in Dialysis Access Steal Syndrome and assess their safety and effectiveness .

Take away point

Percutaneous interventions in patients with Dialysis Access Steal Syndrome was demonstrated to provide symptomatic improvement, and decrease the need for follow up surgical intervention.

Reference

Rigsby DC, Clark TWI, Vance AZ, Chittams J, Cohen R, Mantell MP, Kobrin S, Trerotola SO. Percutaneous Management of Dialysis Access Steal Syndrome: Interventions and Outcomes from a Single Institution's 20-Year Experience. J Vasc Interv Radiol. 2024 Apr;35(4):601-610. doi: 10.1016/j.jvir.2023.12.566. Epub 2024 Jan 1. PMID: 38171415.

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Study design

Retrospective single institutional study

Funding Source

None reported

Setting

Academic: Perelman School of Medicine, University of Pennsylvania

Figure

Figure 1. Flow diagram describing patient progression from initial dialysis access steal syndrome (DASS) evaluation by a referring surgeon to interventional radiology (IR) percutaneous study with or without intervention to follow-up. DRAE = distal radial artery embolization.

Summary

 
Dialysis access steal syndrome (DASS) occurs when blood flows preferentially through the dialysis access circuit, depriving downstream tissues of oxygen-rich blood. This can lead to pain, ulcers, and tissue loss in the ipsilateral limb in up to 10% of dialysis patients. Known risk factors for DASS include older age, female sex, diabetes mellitus, coronary artery disease and peripheral arterial disease. Fistulography is recommended for initial diagnostic workup of DASS and can define the vascular anatomy and assess the degree of intervention required. Percutaneous interventions like distal radial artery embolization and minimally invasive ligation endoluminal-assisted revision percutaneous banding procedure can be performed and are described as the percutaneous equivalents to open surgeries, which include surgical access banding, distal revascularization with interval ligation, and distal radial artery ligation. Access ligation, which is the definitive treatment, is used sparingly due to the importance of maintaining hemodialysis access. Data on the clinical performance of percutaneous interventions is limited.

This study used data from a single institution over a period of 20 years. A retrospective chart review was performed for the 212 patients with 286 fistulograms meeting the inclusion criteria. Patient symptoms were recorded, flow through the access was quantified using a flow measurement (ReoCath, Transonic) catheter and categorized via the 2019 Kidney Disease Outcomes Quality Initiative. Each case fell into one of two categories: diagnostic fistulogram alone or undergoing fistulogram plus intervention. Technical success of the procedure was measured by reporting standards published by the Society of Interventional Radiology and clinical success by any reported improvement in DASS symptoms at the next follow up visit. Patients with severe ischemic tissue loss who received prompt surgical intervention were excluded.

The authors used a multiple logistic regression model to analyze the data, investigating the associations between DASS intervention and major adverse events, access preservation, and follow up surgery. Access was considered not preserved if follow up visit notes contained any indication of access abandonment or takedown. Covariates that were used in the regression model were female sex, upper arm access location, graft access type, diabetes mellitus, coronary artery disease and peripheral arterial disease. Odds ratios were also adjusted for correlation among multiple within-patient events using the robust Huber-White procedure.

Fistulograms revealed that 45% of patients had percutaneously treatable causes of DASS. Previous studies have reported anywhere from 20%-83% of patients having treatable causes of steal, but only about 33% of those patients underwent fistulograms before surgery. Two patients experienced adverse events that included a left common femoral artery hematoma and chest pain that required a 2-day hospital admission. The DASS interventions in this study demonstrated high rates of technical (94.0%) and clinical (54.2%) success that were consistent with similar modalities performed by vascular surgery. Analysis identified that the intervention group had 60% lower odds of follow up surgery and 70% lower odds of undergoing access revision surgery. Hemodialysis access preservation rate did not differ between the intervention and nonintervention groups, at an encouraging 88.0%.

There are limitations to this study that are due to its design, as a retrospective review it is unable to determine causality. The restriction to a single center also decreases the generalizability of the results to a broader population. There was a lack of complete follow up data due to an absence of standardized follow up intervals. This was mentioned by the authors that the true clinical success rate could be anywhere from 44% to 54% if all patients that were lost to follow up were accounted for.

Commentary

With an increasing prevalence of people receiving hemodialysis access, this study adds a large patient cohort to the Interventional Radiology literature on percutaneous management of DASS. Their analysis, which revealed that percutaneous interventions provided comparable outcomes to surgical interventions while maintaining a minimal side effect profile, was well designed and appropriately accounted for possible confounding variables. The implication was that Interventional Radiology can play a bigger role in the management algorithm of DASS and percutaneous interventions should be considered the first-line treatment for DASS. As the authors correctly noted, further research focusing on establishing causality through randomized control trials and investigating possible unintended consequences of percutaneous venous outflow optimization will elucidate the roles of percutaneous DASS interventions better.

Post Author

Anthony M. Camargo, BA
MD candidate, Class of 2025
University of Massachusetts Chan Medical School
@anthonymcamargo

Infrapopliteal Calcium Score for PAD

Clinical Utility of Infrapopliteal Calcium Score for the Evaluation of Severity of Peripheral Artery Disease

Clinical question

To identify associations between computed tomography (CT)–based lower-extremity calcium score (LECS) across different anatomic segments and the presence, severity, and clinical outcomes of peripheral artery disease (PAD).

Take away point

An infrapopliteal calcium score of >188 Agatston units was associated with increased odds of having CLTI and was a potent predictor of CLTI and all-cause mortality among claudicants who were prospectively followed.

Reference

Lee, Sujin, Mari Tanaka, Shiv Patel, Nikolaos Zacharias, Sandeep Hedgire, Rajeev Malhotra, and Anahita Dua. "Clinical Utility of Infrapopliteal Calcium Score for the Evaluation of Severity of Peripheral Artery Disease." Journal of Vascular and Interventional Radiology 35, no. 3 (2024): 370-376.

Click here for abstract

Study design

Retrospective multi-institutional database with a prospective component for model validation

Funding Source

None reported

Setting

Academic

Figure

Kaplan–Meier and Cox proportional hazards analysis of chronic limb-threatening ischemia (CLTI) and death among claudicants. Patients with an infrapopliteal calcium score of ≥188 had a significantly higher risk of progressing to CLTI or death compared with those with a calcium score of <188 (log-rank P = .0036). On the univariate Cox proportional hazards model, an infrapopliteal calcium score of ≥188 was associated with a hazard ratio of 5.58 for CLTI or death (P = .0095). LECS = lower-extremity calcium score.

Summary

Vascular calcification is a key feature of atherosclerotic cardiovascular disease, the leading global cause of morbidity and mortality. In peripheral artery disease (PAD), calcification in the lower extremities correlates with increased severity of ischemia and heightened risk of amputation. Despite evidence linking calcification in specific segments to adverse outcomes, the relationship between calcification at different anatomical sites and peripheral artery disease symptom severity remains unclear. This knowledge gap is particularly relevant as current guidelines recommend intervention only at advanced stages of peripheral artery disease symptoms. There is a need for quantitative markers. This study aims to establish associations between computed tomography-based lower-extremity calcium scores and peripheral artery disease symptom presence and severity, to enhance risk assessment and facilitate timely intervention.

This study utilized a multi-institutional database to evaluate patients who underwent CT angiography of the aorta and bilateral lower-extremity runoff between January 2016 and January 2020. Patients were categorized based on documented symptoms, including claudication, ischemic rest pain, and ulcers. A total of 139 patients met inclusion criteria. Lower-extremity calcium scores (LECSs) were quantified using the Agatston method on CT angiography images. Additionally, ankle-brachial index (ABI) and toe-brachial index (TBI) values obtained within 6 months of the CT scan were included. The optimal cutoff point for infrapopliteal calcium score in identifying patients with chronic limb-threatening ischemia (CLTI) was determined using the Youden J statistic and validated using bootstrapping technique. A prospective cohort of claudicants was followed until October 2022 for CLTI and all-cause mortality.

Multivariable analysis identified only hemodialysis and lower ankle-brachial index (ABI) as independent factors associated with increased odds of claudication. Lower-extremity calcium score in any of the anatomic segments was not independently associated with having claudication. On the other hand, multivariable analysis confirmed the independent association of high infrapopliteal calcium scores with CLTI, along with inability to perform daily activities and absence of hemodialysis dependence. Receiver operating characteristic analysis demonstrated improved predictive accuracy for CLTI when including infrapopliteal calcium scores in the model. Prospective follow-up of claudicants revealed that those with infrapopliteal calcium scores ≥188 Agatston units had a significantly higher risk of progressing to CLTI or death compared to those with lower scores. Cox proportional hazards analysis confirmed infrapopliteal calcium score as a robust predictor of CLTI-free survival, even after adjusting for potential confounders.

Arterial calcification is an independent risk factor for cardiovascular morbidity and mortality, but its impact on lower-extremity vasculature remains less understood. CT-based quantification of lower-extremity arterial calcification provides valuable information for risk stratification in PAD patients. Higher infrapopliteal calcium scores may identify patients at earlier stages of disease progression, enabling timely interventions to prevent CLTI and associated adverse outcomes.

Limitations of the study include its small sample size and retrospective design. Additionally, certain factors such as hemodialysis and surgical bypass procedures may confound the associations observed. Further prospective studies with larger cohorts are needed to validate the utility of infrapopliteal calcium score in evaluating peripheral arterial disease progression and guiding clinical management.

Commentary

This is a well done and well written study on the clinical utility of CT lower extremity calcium score for the evaluation of peripheral arterial disease. The methods and statistical analyses were appropriate and the prospective validation was appreciated. The findings have several implications for the management of peripheral arterial disease. First, infrapopliteal calcium score can serve as a prognostic indicator, enabling clinicians to identify claudicants who are at highest risk of disease progression. Second, infrapopliteal calcium scores can inform clinical decision-making regarding the timing and type of interventions. Overall, this study underscores the potential of CT-based lower-extremity arterial calcium score as a valuable tool in the evaluation and management of peripheral arterial disease. Further research and validation studies are warranted to confirm these findings and integrate infrapopliteal calcium scoring into clinical practice effectively.

Percutaneous Lumbar Discectomy (PLD)

Patient-Reported Outcomes and Return to Work after CT-Guided Percutaneous Lumbar Discectomy: A Prospective Study

Clinical question

What capabilities does percutaneous lumbar discectomy have in reducing pain and increasing functional capacities for patients with symptomatic lumbar disc herniation?

Take away point

87% of employed patients were able to return to work during the follow-up, with a median time of 8 days post procedure.

Reference

Ranc, P.-A., Rudel, A., Bentellis, I., Prestat, A., Elbaze, S., Sala, V., Torre, F., Pavan, L.-J., Uri, I. F., & Amoretti, N. (2024). Patient-reported outcomes and return to work after CT-guided percutaneous lumbar discectomy: A prospective study. Journal of Vascular and Interventional Radiology, 35(3), 390–397. https://doi.org/10.1016/j.jvir.2023.12.007

https://www.jvir.org/article/S1051-0443(23)00896-5/fulltext

Study design

Prospective, observational, descriptive

Funding Source

None

Setting

Academic single center, Pasteur 2 Hospital University Medical Center (Nice, France)

Figure

Evolution of the Oswestry disability index (ODI) during the first 6 months

Summary

The purpose of this study was to understand the effectiveness of percutaneous lumbar discectomy under combined CT and fluoroscopic guidance, specifically its effects on pain relief, the length of recovery through hospital stays and/or time taken to return to work. Evaluation of patient-reported outcomes based on validated functional disability indices was also performed.

This study had 87 patients, 57 of which were employed with a median age of 56. The criteria were lumbar radicular pain visualized on magnetic resonance, failure of conservative treatment, and failure or recurrence after a peri-radicular nerve block. Patients were excluded if they had lumbar stenosis, neurologic deficits, or history of previous surgical discectomy at site of pain.

An initial planning CT was obtained to determine the access and approach for the procedure. Transdural or juxtadural access were preferred for central canal zone or subarticular zone hernias, and posterolateral or lateral approaches for herniation of foraminal and extraforaminal topography. 20-gauge guide needle was introduced to the herniated disc with contrast confirmation of its position. The Herniatome decompression probe was utilized for fragmentation and aspiration. Technical success was defined by correct targeting and tactile feedback.

The data gathered included pain measurements with visual analog scale, duration of the symptoms up to 1 year before treatment, the treated lumbar level, and topography of the herniated disc. The Oswestry disability index was obtained by questionnaire to evaluate the degree of functional disability. The participants were followed-up at 1-month interval with a lumbar MRI to evaluate any complications, then at 3 and 6 months through a blinded observer call.

The median Oswestry disability index decreased from 44 to 20 in 1 month, to 12 within 3 months, and to 7 at 6 months showing a significant increase in functionality (P < .001). At the end of follow-up, for 85% of the patients a decrease in visual analog scale score of >50% was found. With regard to the length of hospital stay, 96.5% were discharged on the same day of procedure, with the remaining patients being discharged the next day. Of the 57 actively working patients, 50 (88%) returned to work after a median time of 8 days. There were no major adverse events.

These results were consistent with those of the study by Liu et al, which evaluated the evolution of Oswestry disability index as well as differences in patients treated with endoscopic discectomy vs. percutaneous discectomy. McCormick et al also showed a 30% decrease in Oswestry indices with a different decompression probe. Ultimately, this study showed a significant decrease in the Oswestry disability index and an improvement in functional capacities after CT-guided percutaneous lumbar discectomy, leading to a faster return to work time which translates to higher patient satisfaction and decreased socioeconomic burden.

Commentary

In light of the increased incidence of younger adults developing disc herniation, this study highlights the medical and economic benefits of minimally invasive techniques in patients with refractory herniated disc syndromes. The effectiveness profile of percutaneous lumbar discectomy was comparable to previously published retrospective studies. But the current prospective study enabled evaluation of the socioeconomic impact. The methods of study were adequate in providing both qualitative and quantitative analyses. Nonetheless, as the authors rightly noted, a control group to analyze the differences compared to surgical or conservative methods would provide more real-world implications. It is clear from the data though that percutaneous lumbar discectomy has clinical and economic significance as illustrated by the median visual analog score decrease of 6 and median return-to-work time of 8 days. Minimally invasive percutaneous approaches are powerful and cost-effective additions to the refractory herniated disc management toolkit.

Post Author

Christopher Loiselle, MS, OMSIV
Lincoln Memorial University-DeBusk College of Osteopathic Medicine
@Caloiselle