Congenital Renal Arteriovenous Malformation: Diagnostic Clues and Methods

Background and objectives: Renal arteriovenous malformation (AVM) is a rare disease and is difficult to be diagnosed by conventional methods because of its rarity. In this study, we investigated the diagnostic clues, and made an algorithm for the better diagnosis of renal AVM. Materials and Methods: We reviewed 13 patients who were diagnosed with AVM by using renal angiography from 1986 to 2020 at our institutes. We evaluated clinical features, diagnostic tools, treatment modalities, and outcomes after the treatment of patients. Results: All patients were female, and the mean age was 36.9 years (range 19 to 54 years). Twelve (92.3%) patients complained of gross hematuria. Four (30.8%) patients showed symptoms in relation with pregnancy and delivery. Angiographic findings demonstrated cirsoid type in 10 patients and aneurysmal type in 3 patients. Among the 11 patients who underwent computed tomography, AVMs were detected in 3 (27.3%) patients. Renal duplex Doppler was performed in 6 patients, and all of these patients were diagnosed with AVM, demonstrating a vascular turbulence or blood-rich area. Twelve patients were initially treated with transarterial embolization. Nephrectomy was performed in two patients due to persistent bleeding with hypovolemic shock. Conclusions: We should consider possible AVMs in patients who were not detected by conventional work up for hematuria, especially in mid-aged, pregnant, or recently delivered women. Renal duplex Doppler might be the optimal diagnostic modality in these patients. Our diagnostic algorithm could be aid to diagnosis and treatment for renal AVM patients.

The role of Doppler ultrasonography in vascular access surveillance—controversies continue

Chronic hemodialysis therapy required regular entry into the patient’s blood stream with adequate flow. The use of arteriovenous fistulas and grafts is linked with lower morbidity and mortality than the use of catheters. However, these types of accesses are frequently affected by stenoses, which decrease the flow and lead to both inadequate dialysis and access thrombosis. The idea of duplex Doppler ultrasound surveillance is based on the presumption that in-time diagnosis of an asymptomatic significant stenosis and its treatment prolongs access patency. Details of performed trials are conflicting, and current guidelines do not support ultrasound surveillance. This review article summarizes the trials performed and focuses on the reasons of conflicting results. We stress the need of precise standardized criteria of significant access stenosis and the weakness of the metaanalyses performed.

MO774PREDICTIVE FACTORS FOR PROSTHESIC ARTERIOVENOUS FISTULA OPTION BY DUPLEX DOPPLER ULTRASOUND VASCULAR MAPPING

Background and Aims Vascular access (VA) remains the lifeline for hemodialysis (HD) patients. Arteriovenous fistulas (AVF) are recommended over prosthesic arteriovenous fistula (PAF). However, the choice of the type of VA still reflects local practice differences and patient-specific demographic and clinical factors. Duplex Doppler ultrasound (DDU) has been shown to be useful in evaluation of both structural and functional aspects of the peripheral vessels, and is emerging as the preferred method for VA planning. Our aim was to find predictive factors for PAF creation in our population, i.e. when AVF was not feasible. Method We retrospectively analysed a cohort of chronic kidney disease patients who underwent DDU vascular mapping for preoperative planning of HD access at a tertiary referral centre from 2019 to 2020. All the exams were performed by the same DDU operator. Demographic, clinical and DDU characteristics were studied. Continuous variables were recorded as means (±SD) for normally distributed data or as medians (interquartile ranges) for non-normally distributed data. Comparisons were made using t tests or Wilcoxon rank sum tests as appropriate. Categorical variables were evaluated by frequency distribution and recorded as proportions. Comparisons were made using the x2 test. Unadjusted and adjusted multivariate logistic regression models were fitted to identify risk factors to PAF creation due to not being a good candidate for AVF. Results A total of 252 patients were included. The mean age was 65±16 years, 144 (57%) were male, 211 (84%) where white, 40 (16%) were black and 1 (0.4%) was asian. Two hundred and thirty seven (94%) patients were right-handed and 186 (74%) were being evaluated for the first vascular access. The majority had arterial hypertension (HT) (205 (81%)); 98 (39%) had Diabetes Mellitus (DM), 89 (35%) were current or past smoker and 72 (29%) were obese. Most patients were considered appropriate candidates for AVF (207, 82%), whereas 45 (18%) were assigned to PAF. Figure 1 compares the DDU’s arterial indexes of each group. In a multivariate logistic regression model adjusted for age, sex, HT, DM and obesity, black race was found to be a predictor of being a candidate for PAV creation (OR 2.46; CI 95% 1.05-5.71; p-value 0.036). Conclusion Our study revealed that black race is an independent factor for PAV creation even after adjusting for classic risk factors as age, DM or HT. Long known insidious factors, such as poor socioeconomic status or poor access to medical care, have been pointed as justifiers to this disparity. However, facing the PAF-associated risks, we believe that further work must be done to clarify potential involved anatomical factors and potential reversible factors. Those patients have been described throughout the literature as presenting with higher risk of VA failure and severe peripheral arterial disease. In parallel we found that radial and ulnar arteries diameters and radial pulse wave velocity (PWV) in DDU were significantly lower in PAV-submitted patients, suggesting distal arterial compromise and stiffness. Our work has some limitations: neither vein parameters nor VA outcomes were analysed. However, it introduces a relationship between the black race and worse arterial indexes, and their impact on the choice of type of VA, as they seem not to be good candidates for AVF.

Clinical accuracy of reverse Barbeau test in the diagnosis of radial artery occlusion after transradial catheterization

Background Radial artery occlusion is an infrequent complication of transradial catheterization. Assessment of radial artery occlusion is a critical aspect of clinical care, and it should be done with an additional test, commonly by a plethysmographic test (reverse Barbeau test) or ultrasound (Doppler), the last is the gold standard. The objective of this study was to evaluate the accuracy of the reverse Barbeau test in detecting radial artery occlusion after transradial catheterization. Methods A study carried out in two centers encompassing patients submitted to procedures by radial access. All patients received at least 5,000IU of heparin. Sheaths were immediately removed after the procedure, using a patent hemostasis protocol. Patency of the radial artery was verified by reverse Barbeau test and duplex Doppler evaluation within the first 24 hours. Results A total of 350 patients were enrolled, with a mean age of 61.7 (±9.7) years. Radial artery occlusion was verified after the procedure in 19 (5.4%) patients, using duplex Doppler scan. Application of reverse Barbeau test had the following results: 64.0% type A curve, 15.7% type B, 8.3% type C, and 12.0% type D (the last suggesting occlusion). With reverse Barbeau test, patients with confirmed occlusion by ultrasound evaluation, 21.1% would be missed by a false-negative test, and in the ones, without radial artery occlusion, 8.2% would be misdiagnosed as having it (sensibility 78.9%; specificity 91.8%). Conclusion Reverse Barbeau test has good accuracy to detect radial artery occlusion, and it is a good option for clinical day use, although using reverse Barbeau test results in the overestimation of radial artery occlusion.

The Analysis of Selected Morphological and Hemodynamic Parameters of the Venous System and Their Presumable Impact on the Risk of Recurrence after Varicose Vein Treatment

Introduction: The current treatment of venous disease is focused on reflux elimination in main venous trunks, especially in the saphenous vein. However, a high recurrence rate, independent of the method of treatment, suggests that the reason of low effectiveness may be due to a strategy focused on symptoms, without considering their origin. Method: The aim of study was the comparison of retrospective data from 535 women with venous disease, either after treatment (n = 183) or not treated before (n = 352). The analysis concerned clinical symptoms and the results of the extended diagnostics, including the examination of the lower limb, pelvic and abdominal veins either using duplex-doppler ultrasound as well as venography with computed tomography or magnetic resonance. Results: The comparison of selected venous system parameters revealed more advanced disease progression in previously treated patients, compared to non-treated individuals (e.g., ipsi- or bilateral incompetence of sapheno-phemoral junction—29.5% vs. 20.4%, at P < 0.05 and 13.6% vs. 7.7% at P < 0.05, respectively). This difference could be explained by post-treatment alterations in the venous system, an older age and the higher number of pregnancies in the recurrence group. However, both groups did not differ in regards to the symptoms of pelvic venous insufficiency or the frequency of relevant variants/abnormalities in venous system. Conclusions: Based on the aforementioned findings, we postulate the revision of treatment strategy, which should consider abdominal and pelvic veins as the source of reflux in many female subjects.

The management of acute knee dislocations: A global survey of orthopaedic surgeons’ strategies

Purpose: Great variety and controversies surround the management strategies of acute multiligament knee injuries (aMKLIs) and no established guidelines exist for resource-limited practices. The aim of this study was to compare the management approach of acute knee dislocations (AKDs) by orthopedic surgeons from nations with different economic status. Methods: This descriptive cross-sectional scenario-based survey compares different management strategies for aMLKIs of surgeons in developed economic nations (DEN) and emerging markets and developing nations (EMDN). The main areas of focus were operative versus non-operative management, timing and staging of surgery, graft choice and vascular assessment strategies. The members of the Societe Internationale de Chirurgie Orthopedique et de Traumatologie (SICOT) were approached to participate and information was collected regarding their demographics, experience, hospital setting and management strategies of aMLKIs. These were analyzed after categorizing participants into DEN and EMDN based on the gross domestic product (GDP) per capita. Results: One-hundred and thirty-eight orthopedic surgeons from 47 countries participated in this study, 67 from DEN and 71 (51.4%) from EMDN. DEN surgeons had more years of experience and were older (p < 0.05). Surgeons from EMDN mostly worked in public sector hospitals, were general orthopedic surgeons and treated patients from a low-income background. They preferred conservative management and delayed reconstruction with autograft (p < 0.05) if surgery was necessary. Surgeons from DEN favored early, single stage arthroscopic ligament reconstruction. Selective Computerized Tomography Angiography (CTA) was the most preferred choice of arterial examination for both groups. Significantly more EMDN surgeons preferred clinical examination (p < 0.05) and duplex doppler scanning (p < 0.05) compared to DEN surgeons. More surgeons from EMDN did not have access to a physiotherapist for their patients. Conclusions: Treatment of aMLKIs vary significantly based on the economic status of the country. Surgeons from DEN prefer early, single stage arthroscopic ligament reconstruction, while conservative management is favored in EMDN. Ligament surgery in EMDN is often delayed and staged. EMDN respondents utilize duplex doppler scanning and clinical examination more readily in their vascular assessment of aMLKIs. These findings highlight very distinct approaches to MLKIs in low-resource settings which are often neglected when guidelines are generated.

Ultrasound speckle tracking to detect vascular distensibility changes from angioplasty and branch ligation in a radio-cephalic fistula: Use of novel open source software

We used novel open source software, based on an ultrasound speckle tracking algorithm, to examine the distensibility of the vessel wall of the inflow artery, anastomosis, and outflow vein before and after two procedures. An 83-year-old white man with a poorly maturing radio-cephalic fistula received an angioplasty at the anastomosis followed by branch ligation 28 days later. Duplex Doppler measurements corroborated the blood flow related changes anticipated from the interventions. The experimental distensibility results showed that it is technically feasible to measure subtle vessel wall motion changes with high resolution (sub-millimeter) using standard Digital Imaging and Communications in Medicine (DICOM) ultrasound data, which are readily available on conventional ultrasound scanners. While this methodology was originally developed using high resolution radiofrequency from ultrasound data, the goal of this study was to use DICOM data, which makes this technology accessible to a wide range of users.