Antithrombotic Therapy and Freedom From Bridging Stent Occlusion After Elective Branched Endovascular Repair: A Multicenter International Cohort Study.

CLINICAL IMPACT: Based on our study, no antithrombotic therapy is significantly associated with bridging stent occlusion, and no evidence of the superiority of other antithrombotic therapy exists. Nevertehless, due to the low number of bridging stent occlusions, this study can neither support nor reject the PRINCE2SS recommendations. Further studies with larger cohorts are needed to determine clear guideliness of the best antithrombotic treatment regimen after complex enfovascular aortic repair.

Interventional radiology for prevention and management of postpartum haemorrhage: a single centre retrospective cohort study.

PURPOSE: Postpartum haemorrhage (PPH) remains a leading cause of maternal death despite current medical management. Surgical interventions are still needed for refractory bleeding. Interventional radiology (IR) can be a successful intermediary that avoids the need for hysterectomy. Nevertheless, IR outcome data in a peripartum setting are limited. The objective of this study is to document the efficacy and safety of IR. METHODS: Retrospective study reviewed the records of consecutive patients who underwent peripartum IR from 01/01/2010 until 31/12/2020 in a tertiary academic centre. Patients were divided in a prophylactic and a therapeutic group. Information about interventions before and after IR, and IR specific complications was retrieved. Efficacy was defined by the number of transfusions and additional surgical interventions needed after IR, and safety was assessed by the incidence of IR related complications. RESULTS: Fifty-four patients, prophylactic group (n = 24) and therapeutic group (n = 30), were identified. In both groups, IR was successful with 1.5 ± 2.9 packed cells transfused post-IR (1.0 ± 2.1 prophylactic vs 1.9 ± 3.3 therapeutic; p = 0.261). Additional surgical interventions were required in n = 5 patients (9.2%), n = 1 (4.2%) in the prophylactic vs. n = 4 (13.3%) in the therapeutic group. Complications were reported in n = 12 patients (22.2%), n = 2 (8.3%) prophylactic vs. n = 10 (33.3%) in therapeutic group. Mostly minor complications, as puncture site hematoma or bleeding, were reported in n = 4 (7.4%). Severe complications as necrosis and metabolic complications were reported in n = 2 patients (3.9%). CONCLUSION: IR for prevention and treatment of PPH was highly successful and associated with minor complications.

Adaptive design of experiments to fit surrogate Gaussian process regression models allows fast sensitivity analysis of the input waveform for patient-specific 3D CFD models of liver radioembolization.

BACKGROUND AND OBJECTIVE: Patient-specific 3D computational fluid dynamics (CFD) models are increasingly being used to understand and predict transarterial radioembolization procedures used for hepatocellular carcinoma treatment. While sensitivity analyses of these CFD models can help to determine the most impactful input parameters, such analyses are computationally costly. Therefore, we aim to use surrogate modelling to allow relatively cheap sensitivity analysis. As an example, we compute Sobol's sensitivity indices for three input waveform shape parameters. METHODS: We extracted three characteristic shape parameters from our input mass flow rate waveform (peak systolic mass flow rate, heart rate, systolic duration) and defined our 3D input parameter space by varying these parameters within 75 %-125 % of their nominal values. To fit our surrogate model with a minimal number of costly CFD simulations, we developed an adaptive design of experiments (ADOE) algorithm. The ADOE uses 100 Latin hypercube sampled points in 3D input space to define the initial design of experiments (DOE). Subsequently, we re-sample input space with 10,000 Latin Hypercube sampled points and cheaply estimate the outputs using the surrogate model. In each of 27 equivolume bins which divide our input space, we determine the most uncertain prediction of the 10,000 points, compute the true outputs using CFD, and add these points to the DOE. For each ADOE iteration, we calculate Sobol's sensitivity indices, and we continue to add batches of 27 samples to the DOE until the Sobol indices have stabilized. RESULTS: We tested our ADOE algorithm on the Ishigami function and showed that we can reliably obtain Sobol's indices with an absolute error <0.1. Applying ADOE to our waveform sensitivity problem, we found that the first-order sensitivity indices were 0.0550, 0.0191 and 0.407 for the peak systolic mass flow rate, heart rate, and the systolic duration, respectively. CONCLUSIONS: Although the current study was an illustrative case, the ADOE allows reliable sensitivity analysis with a limited number of complex model evaluations, and performs well even when the optimal DOE size is a priori unknown. This enables us to identify the highest-impact input parameters of our model, and other novel, costly models in the future.

Simplification strategies for a patient-specific CFD model of particle transport during liver radioembolization.

BACKGROUND: Patient-specific 3D computational fluid dynamics (CFD) simulations have been used previously to identify the impact of injection parameters (e.g. injection location, velocity, etc.) on the particle distribution and the tumor dose during transarterial injection of radioactive microspheres for treatment of hepatocellular carcinoma. However, these simulations are computationally costly, so we aim to evaluate whether these can be reliably simplified. METHODS: We identified and applied five simplification strategies (i.e. truncation, steady flow modelling, moderate and severe grid coarsening, and reducing the number of cardiac cycles) to a patient-specific CFD setup. Subsequently, we evaluated whether these strategies can be used to (1) accurately predict the CFD output (i.e. particle distribution and tumor dose) and (2) quantify the sensitivity of the model output to a specific injection parameter (injection flow rate). RESULTS: For both accuracy and sensitivity purposes, moderate grid coarsening is the most reliable simplification strategy, allowing to predict the tumor dose with only a maximal deviation of 1.4 %, and a similar sensitivity (deviation of 0.7 %). The steady strategy performs the worst, with a maximal deviation in the tumor dose of 20 % and a difference in sensitivity of 10 %. CONCLUSION: The patient-specific 3D CFD simulations of this study can be reliably simplified by coarsening the grid, decreasing the computational time by roughly 45 %, which works especially well for sensitivity studies.

Abdominal aneurysm sac thrombus CT density and volume after EVAR: which association with underlying endoleak?

BACKGROUND: Our aim was to analyse abdominal aneurysm sac thrombus density and volume on computed tomography (CT) after endovascular aneurysm repair (EVAR). METHODS: Patients who underwent EVAR between January 2005 and December 2010 and had at least four follow-up CT exams available over the first five years of follow-up were included in this retrospective single-centre study. Thrombus density and aneurysm sac volume were calculated on unenhanced CT scans. Linear mixed models were used for data analysis. RESULTS: Out of 82 patients, 44 (54%) had an endoleak on post-EVAR contrast-enhanced CT. Thrombus density significantly increased over time in both the endoleak and non-endoleak groups, with a slope of 0.159 UH/month (95% confidence interval [CI] 0.115-0.202), p < 0.0001) and 0.052 UH/month (95% CI 0.002-0.102, p = 0.041). In patients without endoleak, a significant decrease in aneurysm sac volume was identified over time (slope -0.891 cc/month, 95% CI -1.200 to -0.581); p < 0.001) compared to patients with endoleak (slope 0.284 cc/month, 95% CI -0.031 to 0.523, p = 0.082). The association between thrombus density and aneurysm sac volume was positive in the endoleak group (slope 1.543 UH/cc, 95% CI 0.948-2.138, p < 0.001) and negative in the non-endoleak group (slope -1.450 UH/cc, 95% CI -2.326 to -0.574, p = 0.001). CONCLUSION: We observed a progressive increase in thrombus density of the aneurysm sac after EVAR in patients with and without endoleak, more pronounced in patients with endoleak. The association between aneurysm volume and thrombus density was positive in patients with and negative in those without endoleak. RELEVANCE STATEMENT: A progressive increase in thrombus density and volume of abdominal aortic aneurysm sac on unenhanced CT might suggest underlying endoleak lately after EVAR. KEY POINTS: Thrombus density of the aneurysm sac after EVAR increased over time. Progressive increase in thrombus density was significantly associated to the underlying endoleak. The association between aneurysm volume and thrombus density was positive in patients with and negative in those without endoleak.

CIRSE Standards of Practice on Management of Endoleaks Following Endovascular Aneurysm Repair.

BACKGROUND: Endoleaks represent the most common complication after EVAR. Some types are associated with ongoing risk of aneurysm rupture and necessitate long-term surveillance and secondary interventions. PURPOSE: This document, as with all CIRSE Standards of Practice documents, will recommend a reasonable approach to best practices of managing endoleaks. This will include imaging diagnosis, surveillance, indications for intervention, endovascular treatments and their outcomes. Our purpose is to provide recommendations based on up-to-date evidence, updating the guidelines previously published on this topic in 2013. METHODS: The writing group was established by the CIRSE Standards of Practice Committee and consisted of clinicians with internationally recognised expertise in endoleak management. The writing group reviewed the existing literature performing a pragmatic evidence search using PubMed to select publications in English and relating to human subjects up to 2023. The final recommendations were formulated through consensus. RESULTS: Endoleaks may compromise durability of the aortic repair, and long-term imaging surveillance is necessary for early detection and correct classification to guide potential re-intervention. The majority of endoleaks that require treatment can be managed using endovascular techniques. This Standards of Practice document provides up-to-date recommendations for the safe management of endoleaks.

Newly Designed, Self-Expanding Large-Bore Nitinol Stents for Symptomatic Central Venous Stenosis: Technical and Long-Term Clinical Outcome.

PURPOSE: To retrospectively analyze the technical and long-term clinical outcome of angioplasty and stenting using the Venovo™ venous stent for the treatment of malignant and benign superior vena cava (SVC) occlusive disease. MATERIALS AND METHODS: Consecutive patients treated with the Venovo™ venous stent for SVC occlusive disease were included. SVC obstruction symptoms were classified according to the Kishi score. The Wilcoxon signed-rank test was used for testing significance of changes. Technical success, defined as correct placement of the stent, completely covering and re-expanding the obstruction, between groups was tested using the Fisher exact test. Overall survival was calculated using the Kaplan-Meier method. RESULTS: Fifty-five patients underwent stent insertion for symptomatic benign (n = 13; 24%) or malignant (n = 42; 76%) SVC occlusive disease. A significant drop in Kishi score, mean 3.91 before versus mean 1.02 after the procedure (P < 0.0001), was observed. In one patient (1.8%), an additional balloon-expandable stent was needed to manage incomplete expansion of the nitinol stent. In one patient, a procedure-related lung embolic complication was noted. Early thrombotic occlusion of the stent occurred in one patient. Late symptomatic restenosis occurred in 3 patients. Overall primary stent patency and primary-assisted stent patency were 86% (95% CI 66-95) and 97% (95% CI 83-100) at 1-year follow-up and 98% (95% CI 87-100), 98% (87-100) at 2-year follow-up, respectively. CONCLUSION: In this retrospective analysis, angioplasty and stent placement using the Venovo™ venous stent is safe and clinically effective for the treatment of both benign and malignant SVC occlusive disease. Reintervention for symptomatic restenosis is rare.

Factors Impacting Survival After Transarterial Radioembolization in Patients with Unresectable Intrahepatic Cholangiocarcinoma: A Combined Analysis of the Prospective CIRT Studies.

PURPOSE: Transarterial radioembolization (TARE) with Yttrium-90 resin microspheres is a treatment option for patients with intrahepatic cholangiocarcinoma (ICC). However, optimising the timing of TARE in relation to systemic therapies and patient selection remains challenging. We report here on the effectiveness, safety, and prognostic factors associated with TARE for ICC in a combined analysis of the prospective observational CIRT studies (NCT02305459 and NCT03256994). METHODS: A combined analysis of 174 unresectable ICC patients enrolled between 2015 and 2020 was performed. Patient characteristics and treatment-related data were collected at baseline; adverse events and time-to-event data (overall survival [OS], progression-free survival [PFS] and hepatic PFS) were collected at every follow-up visit. Log-rank tests and a multivariable Cox proportional hazard model were used to identify prognostic factors. RESULTS: Patients receiving a first-line strategy of TARE in addition to any systemic treatment had a median OS and PFS of 32.5 months and 11.3 months. Patients selected for first-line TARE alone showed a median OS and PFS of 16.2 months and 7.4 months, whereas TARE as 2nd or further treatment-line resulted in a median OS and PFS of 12 and 9.3 months (p = 0.0028), and 5.1 and 3.5 months (p = 0.0012), respectively. Partition model dosimetry was an independent predictor for better OS (HR 0.59 [95% CI 0.37-0.94], p = 0.0259). No extrahepatic disease, no ascites, and < 6.1 months from diagnosis to treatment were independent predictors for longer PFS. CONCLUSION: This combined analysis indicates that in unresectable ICC, TARE in combination with any systemic treatment is a promising treatment option. LEVEL OF EVIDENCE: level 3, Prospective observational.

Comparison of the single-cell and single-nucleus hepatic myeloid landscape within decompensated cirrhosis patients.

Background and aims: A complete understanding of disease pathophysiology in advanced liver disease is hampered by the challenges posed by clinical specimen collection. Notably, in these patients, a transjugular liver biopsy (TJB) is the only safe way to obtain liver tissue. However, it remains unclear whether successful sequencing of this extremely small and fragile tissue can be achieved for downstream characterization of the hepatic landscape. Methods: Here we leveraged in-house available single-cell RNA-sequencing (scRNA-seq) and single-nucleus (snRNA-seq) technologies and accompanying tissue processing protocols and performed an in-patient comparison on TJB's from decompensated cirrhosis patients (n = 3). Results: We confirmed a high concordance between nuclear and whole cell transcriptomes and captured 31,410 single nuclei and 6,152 single cells, respectively. The two platforms revealed similar diversity since all 8 major cell types could be identified, albeit with different cellular proportions thereof. Most importantly, hepatocytes were most abundant in snRNA-seq, while lymphocyte frequencies were elevated in scRNA-seq. We next focused our attention on hepatic myeloid cells due to their key role in injury and repair during chronic liver disease. Comparison of their transcriptional signatures indicated that these were largely overlapping between the two platforms. However, the scRNA-seq platform failed to recover sufficient Kupffer cell numbers, and other monocytes/macrophages featured elevated expression of stress-related parameters. Conclusion: Our results indicate that single-nucleus transcriptome sequencing provides an effective means to overcome complications associated with clinical specimen collection and could sufficiently profile all major hepatic cell types including all myeloid cell subsets.

SurLym trial: study protocol for a multicentre pragmatic randomised controlled trial on the added value of reconstructive lymphatic surgery to decongestive lymphatic therapy for the treatment of lymphoedema.

INTRODUCTION: Lymphoedema is a chronic condition caused by lymphatic insufficiency. It leads to swelling of the limb/midline region and an increased risk of infection. Lymphoedema is often associated with mental and physical problems limiting quality of life. The first choice of treatment is a conservative treatment, consisting of exercises, skin care, lymph drainage and compression. Reconstructive lymphatic surgery is also often performed, that is, lymphovenous anastomoses, lymph node transfer or a combination. However, robust evidence on the effectiveness of reconstructive lymphatic surgery is missing. Therefore, the objective of this trial is to investigate the added value of reconstructive lymphatic surgery to the conservative treatment in patients with lymphoedema. METHODS AND ANALYSIS: A multicentre randomised controlled and pragmatic trial was started in March 2022 in three Belgian university hospitals. 90 patients with arm lymphoedema and 90 patients with leg lymphoedema will be included. All patients are randomised between conservative treatment alone (control group) or conservative treatment with reconstructive lymphatic surgery (intervention group). Assessments are performed at baseline and at 1, 3, 6, 12, 18, 24 and 36 months. The primary outcome is lymphoedema-specific quality of life at 18 months. Key secondary outcomes are limb volume and duration of wearing the compression garment at 18 months. The approach of reconstructive lymphatic surgery is based on presurgical investigations including clinical examination, lymphofluoroscopy, lymphoscintigraphy, lymph MRI or CT angiography (if needed). All patients receive conservative treatment during 36 months, which is applied by the patient's own physical therapist and by the patient self. From months 7 to 12, the hours a day of wearing the compression garment are gradually decreased. ETHICS AND DISSEMINATION: The study has been approved by the ethical committees of University Hospitals Leuven, Ghent University Hospital and CHU UCL Namur. Results will be disseminated via peer-reviewed journals and presentations. TRIAL REGISTRATION NUMBER: NCT05064176.

Clinical practice recommendations for kidney involvement in tuberous sclerosis complex: a consensus statement by the ERKNet Working Group for Autosomal Dominant Structural Kidney Disorders and the ERA Genes & Kidney Working Group.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by the presence of proliferative lesions throughout the body. Management of TSC is challenging because patients have a multifaceted systemic illness with prominent neurological and developmental impact as well as potentially severe kidney, heart and lung phenotypes; however, every organ system can be involved. Adequate care for patients with TSC requires a coordinated effort involving a multidisciplinary team of clinicians and support staff. This clinical practice recommendation was developed by nephrologists, urologists, paediatric radiologists, interventional radiologists, geneticists, pathologists, and patient and family group representatives, with a focus on TSC-associated kidney manifestations. Careful monitoring of kidney function and assessment of kidney structural lesions by imaging enable early interventions that can preserve kidney function through targeted approaches. Here, we summarize the current evidence and present recommendations for the multidisciplinary management of kidney involvement in TSC.

Evolution of spontaneous portosystemic shunts over time and following aetiological intervention in patients with cirrhosis.

Background & Aims: Spontaneous portosystemic shunts (SPSS) develop frequently in cirrhosis. Changes over time and the effect of aetiological interventions on SPSS are unknown, so we aimed to explore the effect of these variables on SPSS evolution. Methods: Patients with cirrhosis from the Baveno VI-SPSS cohort were selected provided a follow-up abdominal CT or MRI scan was available. Clinical and laboratory data were collected at baseline and follow-up. Imaging tests were reviewed to evaluate changes in the presence and size of SPSS (large (L)-SPSS was ≥8 mm) over time. Regarding alcohol- or HCV-related cirrhosis, two populations were defined: cured patients (abstinent from alcohol or successful HCV therapy), and non-cured patients. Results: A total of 617 patients were included. At baseline SPSS distribution was 22% L-SPSS, 30% small (S)-SPSS, and 48% without (W)-SPSS. During follow-up (median follow-up of 63 months), SPSS distribution worsened: L-SPSS 26%, S-SPSS 32%, and W-SPSS 42% (p <0.001). Patients with worse liver function during follow-up showed a simultaneous aggravation in SPSS distribution. Non-cured patients (n = 191) experienced a significant worsening in liver function, more episodes of liver decompensation and lower transplant-free survival compared to cured patients (n = 191). However, no differences were observed regarding SPSS distribution at inclusion and at follow-up, with both groups showing a trend to worsening. Total shunt diameter increased more in non-cured (52%) than in cured patients (28%). However, total shunt area (TSA) significantly increased only in non-cured patients (74 to 122 mm2, p <0.001). Conclusions: The presence of SPSS in cirrhosis increases over time and parallels liver function deterioration. Aetiological intervention in these patients reduces liver-related complications, but SPSS persist although progression is decreased. Impact and implications: There is no information regarding the evolution of spontaneous portosystemic shunts (SPSS) during the course of cirrhosis, and especially after disease regression with aetiological interventions, such as HCV treatment with direct-acting antivirals or alcohol abstinence. These results are relevant for clinicians dealing with patients with cirrhosis and portal hypertension because they have important implications for the management of cirrhosis with SPSS after disease regression. From a practical point of view, physicians should be aware that in advanced cirrhosis with portal hypertension, after aetiological intervention, SPSS mostly persist despite liver function improvement, and complications related to SPSS may still develop.