Epigenetic and metabolic reprogramming of fibroblasts in Crohn's disease strictures reveals histone deacetylases as therapeutic targets.

BACKGROUND & AIMS: No effective therapeutic intervention exists for intestinal fibrosis in Crohn's disease [CD]. We characterised fibroblast subtypes, epigenetic and metabolic changes, and signalling pathways in CD fibrosis to inform future therapeutic strategies. METHODS: We undertook immunohistochemistry, metabolic, signalling pathway and Epigenetic [Transposase-Accessible Chromatin using sequencing] analyses associated with collagen production in CCD-18Co intestinal fibroblasts and primary fibroblasts isolated from stricturing [SCD] and non-stricturing [NSCD] CD small intestine. SCD/ NSCD fibroblasts were cultured with TGFß and valproic acid [VPA]. RESULTS: Stricturing CD was characterised by distinct histone deacetylase [HDAC] expression profiles, particularly HDAC1, HDAC2, and HDAC7. As a proxy for HDAC activity, reduced numbers of H3K27ac+ cells were found in SCD compared to NSCD sections. Primary fibroblasts had increased extracellular lactate [increased glycolytic activity] and intracellular hydroxyproline [increased collagen production] in SCD compared to NSCD cultures. The metabolic effect of TGFß-stimulation was reversed by the HDAC inhibitor VPA. SCD fibroblasts appear "metabolically primed" and responded more strongly to both TGFß and VPA. Treatment with VPA revealed TGFß-dependent and independent Collagen-I production in CCD-18Co cells and primary fibroblasts. VPA altered the epigenetic landscape with reduced chromatin accessibility at the COL1A1 and COL1A2 promoters. CONCLUSIONS: Increased HDAC expression profiles, H3K27ac hypoacetylation, a significant glycolytic phenotype, and metabolic priming, characterise SCD-derived as compared to NSCD fibroblasts. Our results reveal a novel epigenetic component to Collagen-I regulation and TGFß-mediated CD fibrosis. HDAC inhibitor therapy may 'reset' the epigenetic changes associated with fibrosis.

Dyskeratosis Congenita Links Telomere Attrition to Age-Related Systemic Energetics.

The underlying mechanisms of plasma metabolite signatures of human aging and age-related diseases are not clear but telomere attrition and dysfunction are central to both. Dyskeratosis congenita (DC) is associated with mutations in the telomerase enzyme complex (TERT, TERC, and DKC1) and progressive telomere attrition. We analyzed the effect of telomere attrition on senescence-associated metabolites in fibroblast-conditioned media and DC patient plasma. Samples were analyzed by gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry. We showed extracellular citrate was repressed by canonical telomerase function in vitro and associated with DC leukocyte telomere attrition in vivo, leading to the hypothesis that altered citrate metabolism detects telomere dysfunction. However, elevated citrate and senescence factors only weakly distinguished DC patients from controls, whereas elevated levels of other tricarboxylic acid cycle (TCA) metabolites, lactate, and especially pyruvate distinguished them with high significance. The DC plasma signature most resembled that of patients with loss of function pyruvate dehydrogenase complex mutations and that of older subjects but significantly not those of type 2 diabetes, lactic acidosis, or elevated mitochondrial reactive oxygen species. Additionally, our data are consistent with further metabolism of citrate and lactate in the liver and kidneys. Citrate uptake in certain organs modulates age-related disease in mice and our data have similarities with age-related disease signatures in humans. Our results have implications for the role of telomere dysfunction in human aging in addition to its early diagnosis and the monitoring of anti-senescence therapeutics, especially those designed to improve telomere function.

Ion-Pairing Chromatography and Amine Derivatization Provide Complementary Approaches for the Targeted LC-MS Analysis of the Polar Metabolome.

Liquid chromatography coupled to mass spectrometry is a key metabolomics/metabonomics technology. Reversed-phase liquid chromatography (RPLC) is very widely used as a separation step, but typically has poor retention of highly polar metabolites. Here, we evaluated the combination of two alternative methods for improving retention of polar metabolites based on 6-aminoquinoloyl-N-hydroxysuccinidimyl carbamate derivatization for amine groups, and ion-pairing chromatography (IPC) using tributylamine as an ion-pairing agent to retain acids. We compared both of these methods to RPLC and also to each other, for targeted analysis using a triple-quadrupole mass spectrometer, applied to a library of ca. 500 polar metabolites. IPC and derivatization were complementary in terms of their coverage: combined, they improved the proportion of metabolites with good retention to 91%, compared to just 39% for RPLC alone. The combined method was assessed by analyzing a set of liver extracts from aged male and female mice that had been treated with the polyphenol compound ampelopsin. Not only were a number of significantly changed metabolites detected, but also it could be shown that there was a clear interaction between ampelopsin treatment and sex, in that the direction of metabolite change was opposite for males and females.

Pathway analysis in metabolomics: Recommendations for the use of over-representation analysis.

Over-representation analysis (ORA) is one of the commonest pathway analysis approaches used for the functional interpretation of metabolomics datasets. Despite the widespread use of ORA in metabolomics, the community lacks guidelines detailing its best-practice use. Many factors have a pronounced impact on the results, but to date their effects have received little systematic attention. Using five publicly available datasets, we demonstrated that changes in parameters such as the background set, differential metabolite selection methods, and pathway database used can result in profoundly different ORA results. The use of a non-assay-specific background set, for example, resulted in large numbers of false-positive pathways. Pathway database choice, evaluated using three of the most popular metabolic pathway databases (KEGG, Reactome, and BioCyc), led to vastly different results in both the number and function of significantly enriched pathways. Factors that are specific to metabolomics data, such as the reliability of compound identification and the chemical bias of different analytical platforms also impacted ORA results. Simulated metabolite misidentification rates as low as 4% resulted in both gain of false-positive pathways and loss of truly significant pathways across all datasets. Our results have several practical implications for ORA users, as well as those using alternative pathway analysis methods. We offer a set of recommendations for the use of ORA in metabolomics, alongside a set of minimal reporting guidelines, as a first step towards the standardisation of pathway analysis in metabolomics.

Calm on the surface, dynamic on the inside. Molecular homeostasis of Anabaena sp. PCC 7120 nitrogen metabolism.

Nitrogen sources are all converted into ammonium/ia as a first step of assimilation. It is reasonable to expect that molecular components involved in the transport of ammonium/ia across biological membranes connect with the regulation of both nitrogen and central metabolism. We applied both genetic (i.e., Δamt mutation) and environmental treatments to a target biological system, the cyanobacterium Anabaena sp PCC 7120. The aim was to both perturb nitrogen metabolism and induce multiple inner nitrogen states, respectively, followed by targeted quantification of key proteins, metabolites and enzyme activities. The absence of AMT transporters triggered a substantial whole-system response, affecting enzyme activities and quantity of proteins and metabolites, spanning nitrogen and carbon metabolisms. Moreover, the Δamt strain displayed a molecular fingerprint indicating nitrogen deficiency even under nitrogen replete conditions. Contrasting with such dynamic adaptations was the striking near-complete lack of an externally measurable altered phenotype. We conclude that this species evolved a highly robust and adaptable molecular network to maintain homeostasis, resulting in substantial internal but minimal external perturbations. This analysis provides evidence for a potential role of AMT transporters in the regulatory/signalling network of nitrogen metabolism and the existence of a novel fourth regulatory mechanism controlling glutamine synthetase activity.

Retrieval of Bard Simon Nitinol inferior vena cava filters: Approaches, technical successes, complications, and clinical outcomes.

OBJECTIVE: The Simon Nitinol filter is a bi-level filtration device designed for permanent implantation that is no longer commercially available, but may result in similar complications to current commercially available long term indwelling temporary or permanent filters. Complications related to indwelling inferior vena cava filters include inferior vena cava thrombosis, inferior vena cava penetration, filter migration, and filter fracture. There is a paucity of reports describing the technical aspects related to retrieval of Simon Nitinol filters. MATERIALS AND METHODS: This study consisted of five patients with Simon Nitinol filters and describes the indication for retrieval, the retrieval techniques used to remove the filters, technical success, complications, and clinical course. RESULTS: The indications for retrieval included: abdominal pain (n = 2; 40%), iliocaval thrombosis (n = 1; 20%), identification of an intracardiac filter fragment (n = 1; 20%), and recurrent venous thromboembolic events (n = 1; 20%). Retrieval techniques included: biopsy forceps (n = 3; 60%), excimer laser extraction sheaths (n = 3; 60%), hangman modified loop snares (n = 3; 60%), rigid endobronchial forceps (n = 2; 40%), and balloon deflection (n = 2; 40%). All filters were successfully retrieved. One patient developed a post-procedural intramuscular hematoma near the site of right internal jugular sheath placement. CONCLUSIONS: Simon Nitinol filters may be retrieved safely and effectively using advanced inferior vena cava filter retrieval techniques.

Scholarly Activities and Indices Among Academic Endovascular Specialists: A Comparative Analysis Between Interventional Radiologists and Vascular Surgeons.

PURPOSE: To report scholarly metrics amongst academic endovascular specialists. MATERIAL AND METHODS: Faculty pages identified interventional radiologists and vascular surgeons at academic institutions. Members were classified as assistant, associate, or full professors. Scopus was used to extract publication and citation records. Data extracted included: number of publications, number of citations, h-index, i-10 index, hc-index, m-quotient, e-index, and g-index. RESULTS: Two hundred seventy six interventional radiologists and 266 vascular surgeons were included. Mean publications for interventional radiology assistant, associate, and full professors were 17.81, 48.77, and 131.65 and the citation counts were 311.45, 1051.08, and 3981.71, respectively. Mean publications for vascular surgeon assistant, associate, and full professors were 24.00, 48.7, and 161.37 and the citation counts were 414.33, 1147.89, and 5747.00, respectively. Multivariable proportional odds model for interventional radiologists showed a positive correlation between the academic rank and publication count (c = 0.028), h-index (c = 0.090), i10-index (c = 0.014), hc-index (c = 0.052), e-index (c = 0.016), and g-index (0.037). There was a negative correlation between m-quotient (c = -1.745) and citations (c = -0.001) and academic rank. Multivariable proportional odds model for vascular surgeons showed a positive correlation between the academic rank and publication count (c = 0.037) and g-index (c = 0.083). There was a negative correlation between m-quotient (c = -2.232) and hc-index (c = -0.065) and academic rank. CONCLUSION: Citation count and h-index are positively correlated while m-quotient is negatively correlated with academic performance for endovascular specialists.

Gianturco Z-stent placement for the treatment of chronic central venous occlusive disease: implantation of 208 stents in 137 symptomatic patients.

PURPOSE: To report the technical successes, adverse events, and long-term stent patency rates of Gianturco Z-stents for management of chronic central venous occlusive disease. METHODS: Overall, 137 patients, with mean age 48.6±16.1 years (range, 16-89 years), underwent placement of Gianturco Z-stents for chronic central venous occlusions. Presenting symptoms included lower extremity edema (n=66, 48.2%), superior vena cava syndrome (n=30, 21.9%), unilateral upper extremity swelling (n=20, 14.6%), hemodialysis fistula or catheter dysfunction (n=11, 8.0%), ascites (n=8, 5.8%), and both ascites and lower extremity edema (n=2, 1.5%). Most common etiologies of central venous occlusion were prior central venous access placement (n=58, 42.3%), extrinsic compression (n=29, 21.2%), and post-surgical anastomotic stenosis (n=27, 19.7%). Number of stents placed, stent implantation location, stent sizes, technical successes, adverse events, need for re-intervention, follow-up evaluation, stent patencies, and mortality were recorded. Technical success was defined as recanalization and stent reconstruction with restoration of in-line venous flow. Adverse events were defined by the Society of Interventional Radiology Adverse Event Classification criteria. Primary and primary-assisted stent patencies were analyzed using Kaplan-Meier analysis. RESULTS: In total, 208 Z-stents were placed. The three most common placement sites were the inferior vena cava (n=124, 59.6%), superior vena cava (n=44, 21.2%), and brachiocephalic veins (n=27, 13.0%). Technical success was achieved in 133 patients (97.1%). There were two (1.5%) severe adverse events (two cases of stent migration to the right atrium), one (0.7%) moderate adverse event, and one (0.7%) mild adverse event. Mean follow-up was 43.6±52.7 months. Estimated 1-, 3-, and 5-year primary stent patency was 84.2%, 84.2%, and 82.1%, respectively. Estimated 1-, 3-, and 5-year primary-assisted patency was 92.3%, 89.6%, and 89.6%, respectively. The 30- and 60- day mortality rates were 2.9% (n=4) and 5.1% (n=7), none of which were directly attributable to Z-stent placement. CONCLUSION: Gianturco Z-stent placement is safe and effective for the treatment for chronic central venous occlusive disease with durable short- and long-term patencies.

Fluoroscopically-guided interventions with radiation doses exceeding 5000 mGy reference point air kerma: a dosimetric analysis of 89,549 interventional radiology, neurointerventional radiology, vascular surgery, and neurosurgery encounters.

PURPOSE: To quantify and categorize fluoroscopically-guided procedures with radiation doses exceeding 5000 mGy reference point air kerma (Ka,r). Ka,r > 5000 mGy has been defined as a "significant radiation dose" by the Society of Interventional Radiology. Identification and analysis of interventions with high radiation doses has the potential to reduce radiation-induced injuries. MATERIALS AND METHODS: Radiation dose data from a dose monitoring system for 19 interventional suites and 89,549 consecutive patient encounters from January 1, 2013 to August 1, 2019 at a single academic institution were reviewed. All patient encounters with Ka,r > 5000 mGy were included. All other encounters were excluded (n = 89,289). Patient demographics, medical specialty, intervention type, fluoroscopy time (minutes), dose area product (mGy·cm2), and Ka,r (mGy) were evaluated. RESULTS: There were 260 (0.3%) fluoroscopically-guided procedures with Ka,r > 5000 mGy. Of the 260 procedures which exceeded 5000 mGy, neurosurgery performed 81 (30.5%) procedures, followed by interventional radiology (n = 75; 28.2%), neurointerventional radiology (n = 55; 20.7%), and vascular surgery (n = 49; 18.4%). The procedures associated with the highest Ka,r were venous stent reconstruction performed by interventional radiology, arteriovenous malformation embolization performed by neurointerventional radiology, spinal hardware fixation by neurosurgery, and arterial interventions performed by vascular surgery. Neurointerventional radiology had the highest mean Ka,r (7,799 mGy), followed by neurosurgery (7452 mGy), vascular surgery (6849 mGy), and interventional radiology (6109 mGy). The mean Ka,r for interventional radiology performed procedures exceeding 5000 mGy was significantly lower than that for neurointerventional radiology, neurosurgery, and vascular surgery. CONCLUSIONS: Fluoroscopically-guided procedures with radiation dose exceeding 5000 mGy reference point air kerma are uncommon. The results of this study demonstrate that a large proportion of cases exceeding 5000 mGy were performed by non-radiologists, who likely do not receive the same training in radiation physics, radiation biology, and dose reduction techniques as radiologists.

Thoracic duct embolization in kaposiform lymphangiomatosis.

An 11-year-old girl with kaposiform lymphangiomatosis presented with recurrent chylous pericardial effusions that were refractory to pericardial drainage and medical therapy. Magnetic resonance imaging demonstrated a prominent lymphatic duct with anterior mediastinal extension into the left clavicular region and a region of high signal that was favored to represent a low-flow lymphatic malformation. The patient underwent direct access thoracic duct lymphangiography with thoracic duct embolization and sclerotherapy of the large left-sided neck and pericardial lymphatic malformation. After the procedure, her pericardial effusions resolved, and she has remained asymptomatic for 15 months.

Percutaneous Extra-Anatomic Lymphovenous Bypass Creation: Toward Treatment of Central Conducting Lymphatic Obstructions.

INTRODUCTION: Protein-losing enteropathy manifests as a loss of serum proteins through the gastrointestinal tract, resulting in hypoproteinemia, extravascular fluid retention, and edema. Management consists of nutritional maintenance in conjunction with interventions targeted at treating the underlying etiology. MATERIALS AND METHODS: This report describes a patient with protein-losing enteropathy from a central conducting lymphatic obstruction who was treated with percutaneous extra-anatomic lymphovenous bypass creation. RESULTS: A modified gun-sight technique was used to create a lymphovenous bypass between an occluded terminal thoracic duct and the left internal jugular vein. CONCLUSION: A percutaneous technique to reconstruct the terminal thoracic duct via lymphovenous bypass creation was feasible.

Burnout among Interventional Radiologists.

PURPOSE: To characterize burnout, as defined by high emotional exhaustion (EE) or depersonalization (DP), among interventional radiologists using a validated assessment tool. MATERIALS AND METHODS: An anonymous 34-question survey was distributed to interventional radiologists. The survey consisted of demographic and practice environment questions and the 22-item Maslach Burnout Inventory-Human Services Survey (MBI). Interventional radiologists with high scores on EE (≥ 27) or DP (≥ 10) MBI subscales were considered to have a manifestation of career burnout. RESULTS: Beginning on January 7, 2019, 339 surveys were completed over 31 days. Of respondents, 263 (77.6%) identified as male, 75 (22.1%) identified as female, and 1 (0.3%) identified as trans-male. The respondents were interventional radiology attending physicians (298; 87.9%), fellows (20; 5.9%), and residents (21; 6.2%) practicing at academic (136; 40.1%), private (145; 42.8%), and hybrid (58; 17.1%) centers. Respondents worked < 40 hours (15; 4.4%), 40-60 hours (225; 66.4%), 60-80 hours (81; 23.9%), and > 80 hours (18; 5.3%) per week. Mean MBI scores for EE, DP, and personal achievement were 30.0 ± 13.0, 10.6 ± 6.9, and 39.6 ± 6.6. Burnout was present in 244 (71.9%) participants. Identifying as female (odds ratio 2.4; P = .009) and working > 80 hours per week (odds ratio 7.0; P = .030) were significantly associated with burnout. CONCLUSIONS: Burnout is prevalent among interventional radiologists. Identifying as female and working > 80 hours per week were strongly associated with burnout.

Thoracic Duct Embolization-Value Analysis Using a Time-Driven Activity-Based Costing Approach: A Single Institution Experience.

PURPOSE: To quantify cost drivers for thoracic duct embolization based on time-driven activity-based costing methods. MATERIALS AND METHODS: This was an Institutional Review Board-approved (HUM00141114) and Health Insurance Portability and Accountability Act-compliant study performed at a quaternary care institution over a 14-month period. After process maps for thoracic duct embolization were prepared, staff practical capacity rates and consumable equipment costs were analyzed via a time-driven activity-based costing methodology. Sensitivity analyses were performed to identify primary cost drivers. RESULTS: Mean procedure duration was 4.29 hours (range: 2.15-7.16 hours). Base case cost, per case, for thoracic duct embolization was $7466.67. Multivariate sensitivity analyses performed with all minimum and maximum values for cost input variables yielded a cost range of $1001.95 (minimum) to $89,503.50 (maximum). Using local salary information and negotiated prices for materials as cost parameters, the true cost per case of thoracic duct embolization at the study institution was $8038.94. Univariate analysis demonstrated that the primary driver of staffing costs was the length of time the attending anesthesiologist was present. The predominant modifiable cost drivers included cyanoacrylate glue volume used (minimum $4467; maximum $12,467), cost of glue utilized (minimum $5217; maximum $10,467), and cost of coils utilized (minimum $7377; maximum $10,917). Univariate analysis predicted that the use of Histoacryl glue in place of TRUFILL cyanoacrylate glue resulted in a cost savings of $2947.50 per case. CONCLUSIONS: The base cost per case for thoracic duct embolization was $7466.67. Costs, namely anesthesia staffing costs, cyanoacrylate glue, and coils were large, potentially modifiable drivers of overall cost for thoracic duct embolization.

The occlusion balloon reduction technique for de novo placement and salvage of malpositioned enteric tubes.

PURPOSE: Nasoenteric, gastrojejunostomy, and jejunostomy tubes are methods of enteral nutrition in patients with functioning gastrointestinal tracts who cannot maintain adequate oral intake. Current placements; however, may be complicated by redundant wire and catheter loops within the stomach preventing operators from optimal feeding tube placement and predisposing patients to feeding tube prolapse. This report describes the occlusion balloon reduction technique for salvage of malpositioned tubes and placement of new enteric tubes in the setting of redundant loops. MATERIALS AND METHODS: Five patients underwent the occlusion balloon reduction technique for jejunostomy (n = 3), gastrojejunostomy (n = 1), or nasojejunal tube placement (n = 1). All patients (n = 5) had redundant wires coiled within the stomach. In all patients (n = 5), a 9-French × 32 mm × 120 cm Coda balloon was inserted over the wire and passed into the small bowel. The balloon was inflated after which reduction of redundancy in the upper gastrointestinal tract was performed. Feeding tubes were then placed with tips in the distal jejunum. Technical success of the occlusion balloon reduction technique, successful placement of enteric tube, complications, and follow-up were recorded. RESULTS: The occlusion balloon reduction was technically successful in all patients (n = 5). Feeding tube placement was successful in all patients (n = 5). No minor or major complication occurred. Mean follow-up was 56 days. CONCLUSION: The occlusion balloon reduction technique provides a method for reduction of redundant wire and catheter loops within the stomach during enteric tube placement or repositioning.

13C Labeling of Nematode Worms to Improve Metabolome Coverage by Heteronuclear Nuclear Magnetic Resonance Experiments.

Nuclear magnetic resonance (NMR) spectroscopy is widely used as a metabolomics tool, and 1D spectroscopy is overwhelmingly the commonest approach. The use of 2D spectroscopy could offer significant advantages in terms of increased spectral dispersion of peaks, but has a number of disadvantages-in particular, heteronuclear 2D spectroscopy is often much less sensitive than 1D NMR. One factor contributing to this low sensitivity in 13C/1H heteronuclear NMR is the low natural abundance of the 13C stable isotope; as a consequence, where it is possible to label biological material with 13C, there is a potential enhancement of sensitivity of up to around 90fold. However, there are some problems that can reduce the advantages otherwise gained-in particular, the fine structure arising from 13C/13C coupling, which is essentially non-existent at natural abundance, can reduce the possible sensitivity gain and increase the chances of peak overlap. Here, we examined the use of two different heteronuclear single quantum coherence (HSQC) pulse sequences for the analysis of fully 13C-labeled tissue extracts from Caenorhabditis elegans nematodes. The constant time ct-HSQC had improved peak shape, and consequent better peak detection of metabolites from a labeled extract; matching this against reference spectra from the HMDB gave a match to about 300 records (although fewer actual metabolites, as some of these represent false positive matches). This approach gives a rapid and automated initial metabolome assignment, forming an ideal basis for further manual curation.

Medical Malpractice in Image-Guided Procedures: An Analysis of 184 Cases.

PURPOSE: To report types and outcomes of a small subset of malpractice lawsuits filed against physicians performing image-guided interventions in the United States. MATERIALS AND METHODS: In total, 1,312 cases involving common image-guided procedures were reviewed from the Westlaw and LexisNexis databases in the United States from 1963 to 2018. Social Security, disability, employment contract, product liability, criminal, and government employment claims were excluded. The final legal cohort comprised 184 (14.0%) cases. They were categorized into vascular (113/184; 61.4%), inferior vena cava filter (n = 22; 12.0%), neurointerventional (n = 13; 7.1%), gastrointestinal and genitourinary (n = 17; 9.2%), foreign body (n = 7; 3.8%), biopsy related (n = 9; 4.9%), and oncologic (n = 3; 1.6%) interventions. Claims were also organized by defendant type and by specialty, complication stage, verdict, and year. RESULTS: From 2001 to 2018, 58.7% of claims (n = 108) were reported. Procedural complications related to arteriography were most commonly litigated (63/113; 55.8%). Claims arising from intra-procedural and early post-procedural complications were common (84/184; 45.7%). Community hospitals were most often named as defendants (61/184; 33.2%). In reported outcomes, courts sided with defendants in 81.9% (104/127) of the cases, similar to national malpractice trends. Unreported outcomes comprised 31% (57/184) of the data. CONCLUSIONS: For the small subset of claims published within national legal databases, intra-procedural and early post-procedural complications after diagnostic arteriography were most commonly litigated. Most (81.9%) claims with reported outcomes sided with the defendant physician.

Lower extremity endovenous reconstruction for symptomatic occlusive disease in pediatric patients: techniques, clinical outcomes, and long-term stent patencies.

BACKGROUND: Endovascular stent reconstruction is the standard of care for chronic venous occlusive disease in adults, but it has not been reported in pediatric patients. OBJECTIVE: This study reports the technical success, complications, clinical outcomes, and stent patency of iliocaval stent reconstruction for chronic iliocaval thrombosis in pediatric patients. MATERIALS AND METHODS: Fourteen patients, 13 (93%) male with a mean age of 16.4 years (range: 8-20 years), underwent iliocaval stent reconstruction for chronic iliocaval thrombosis. The mean number of prothrombotic risk factors was 2.5 (range: 0-4), including 7 (50%) patients with inferior vena cava atresia. At initial presentation, the Clinical, Etiology, Anatomy, and Pathophysiology classification (CEAP) score was C3 in 2 (14%) patients, C4 in 11 (79%) patients, and C6 in 1 (7.1%) patient. Time course of presenting symptoms included chronic (>4 weeks) (n=7; 50%) and acute worsening of chronic symptoms (2-4 weeks) (n=7; 50%). Aspects of recanalization and reconstruction, stenting technical success, complications, clinical outcomes and stent patency were recorded. Clinical success was defined as a 1-point decrease in the CEAP. Primary, primary-assisted, and secondary patency were defined by Cardiovascular and Interventional Radiological Society of Europe guidelines. RESULTS: Most procedures employed three access sites (range: 2-4). Intravascular ultrasound was employed in 11 (79%) procedures. Blunt and sharp recanalization techniques were used in 12 (86%) and 2 (14%) patients, respectively. Stenting technical success was 100%. Two (14%) minor adverse events occurred and mean post-procedure hospitalization was 2.8 days (range: 1-8 days). Clinical success rates at 2 weeks, 6 months and 12 months were 85%, 82%, and 83%, respectively. At a mean final clinical follow-up of 88 months (range: 16-231 months), clinical success was 93%. Estimated 6- and 12-month primary stent patencies were 86% and 64%, respectively. Six- and 12-month primary-assisted and secondary stent patency rates were both 100%. CONCLUSION: Iliocaval stent reconstruction is an effective treatment for symptomatic chronic iliocaval thrombosis in pediatric patients with high rates of technical success, 6- and 12-month clinical success, and 6- and 12-month primary-assisted and secondary patency rates.