Correlation between common iliac vein geometry and the risk of deep vein thrombosis in patients with May-Thurner syndrome.

BACKGROUND: May-Thurner syndrome (MTS) is a continuous pathological change of the left common iliac vein intraluminal wall due to compression between the right common iliac artery and a lumbar vertebra, with clinical signs of compromised venous drainage of the left leg, which eventually leads to development of left-sided deep vein thrombosis (DVT). PURPOSE: To analyze the correlation between iliac vessel geometry and probability of DVT in patients with MTS. MATERIAL AND METHODS: This study consists of two age-matched female groups: DVT (n = 21) and control (n = 28). Iliac vein geometry, including left common iliac vein (LCIV) diameter, percentage of stenosis, angle between LCIV and right common iliac vein (RCIV), tilt angle of each CIV with horizontal line, and crossing angle between right common iliac artery (RCIA) and LCIV, were measured on computed tomography venography (CTV) images. The probability of DVT development was assessed using logistic regression. RESULTS: Comparing the DVT and control groups, the mean LCIV diameter was 2.4 mm and 3.7 mm (P = 0.001), and mean LCIV stenosis was 77.7% and 68.3% (P = 0.001), respectively. After age-adjustment, the odds of left DVT in patients with MTS correlated with LCIV diameter (odds ratio [OR]=0.25, P < 0.001, 95% confidence interval [CI]=0.11-0.54), LCIV stenosis (%) (OR=1.12, P = 0.003, 95% CI=1.04-1.21), LCIV tilt angle (OR=0.95, P < 0.038, 95% CI=0.91-0.99), and angle between two CIVs (OR=1.04, P < 0.039, 95% CI=1.00-1.09). CONCLUSION: LCIV diameter and percentage of stenosis, LCIV tilt angle, and CIV angle were independent risk factors for the development of DVT in patients with MTS.

May Measurement Month 2021: an analysis of blood pressure screening campaign results from India.

Raised blood pressure (BP) is the leading preventable risk factor for cardiovascular diseases that makes a major impact on early mortality and morbidity. Recognizing hypertension in the community, educating people about routine BP monitoring, and improving medication compliance are all important steps in detecting, controlling, and managing hypertension. During the course of 5 months, members of the Indian Society of Hypertension organized unique medical indoor and outdoor camps at 100 screening locations around India for the May Measurement Month (MMM) 2021 study. At every location, BP was measured three times, and a questionnaire was completed. Participants known to have hypertension before the study whether taking or not taking treatment were not included (not a normal pre-requisite for exclusion in MMM). The analysis included 15 045 participants in total. After calculating the average of the second and third BP measurements, 16.4% of participants were found to have hypertension based on ≥140/90 mmHg thresholds (2461 out of 15 045). 14.0% of females and 16.4% of males had hypertension. 16.4% of participants had undiagnosed hypertension and were not receiving treatment. The MMM screening campaign has the potential for identifying large numbers of people with undiagnosed hypertension and raising awareness of the importance of raised BP among the general public, medical professionals, policymakers, the government, and the media. Future BP screening campaigns should be larger in scope and involve follow-ups with past participants.

May Measurement Month 2021: an analysis of blood pressure screening results from Kazakhstan.

The May Measurement Month (MMM) screening campaign initiated by the International Society of Hypertension aimed to assess the prevalence of hypertension and associated risk factors to increase and improve population awareness of raised blood pressure (BP) and methods of prevention. The MMM is a cross-sectional survey of adults aged 18 years and over of both sexes who gave informed consent to participate in the survey and to have their BP measured. Kazakhstan participated in the campaign for the first time in 2021. Blood pressure was measured three times on a single occasion, and data on cardiovascular risk factors were collected. A total of 1763 respondents from 4 regions participated in the screening. The mean age was 41 ± 14.4 years; 31.5% of all participants were found to have hypertension, of whom 41.8% were aware, 34.0% on treatment, and only 15.8% controlled (<140/90 mmHg). Significant differences in these rates were found between age and sex groups. The screening campaign confirms low levels of awareness of hypertension and associated risk factors in the population in Kazakhstan and the need for annual screening and implementation of national hypertension control programmes.

Selective iliofemoral stent placement for complex pediatric cases: a decade of institutional experience.

BACKGROUND: Pediatric iliofemoral venous thromboembolism that is resistant to conventional treatments poses significant management challenges. Stent placement represents a potentially underutilized strategy in children when stenosis or thrombosis persists intraprocedurally or recurs postoperatively, despite treatments such as venoplasty, lysis, and thrombectomy. OBJECTIVE: This study aims to report our institutional experience with iliofemoral stenting in 17 pediatric patients with recurrent iliofemoral venous thromboembolism or stenosis. MATERIALS AND METHODS: We performed an IRB-approved retrospective review of pediatric patients (<18 years of age) who underwent iliofemoral venous stenting for recurrent stenosis or thrombosis between January 2012 and December 2022 at a single tertiary care institution. Patient demographics, risk factors for venous thromboembolism, presenting symptoms, and procedural characteristics were recorded. The primary outcome was stent patency rates at interval imaging follow-up. RESULTS: Seventeen patients with mean age of 14.6 years (range 7-17) and mean BMI of 27.7 were stented during the study period. Sixteen of 17 patients presented with evidence of May-Thurner anatomy. 14/17 patients presented with acute iliofemoral venous thromboembolism, 2/17 with chronic venous thromboembolism, and 1/17 with left lower extremity swelling without thrombosis. Seventy-three total angiographic procedures were performed, which included angioplasty, lysis, and thrombectomy, and 23 stent placements. Patients underwent an average of 3 procedures (range 1-9) over a mean of 2.8 months (range 0-17 months) prior to undergoing stent placement. Stents were deployed successfully in all patients. The median follow-up was 18 months (range, 1-77 months). Primary and secondary patency rates were 13/17 (76%) and 14/14 (100%) at 12 months and 12/17 (71%) and 14/14 (100%) at 24 months, respectively. CONCLUSION: In our experience of 17 patients, stent placement appears to be a durable option for children with iliofemoral venous thromboembolism following failure to establish vessel patency or development of recurrent thrombosis/stenosis postoperatively.

The TOPOS study.

Background: We aimed to study the long-term safety and efficacy of oblique venous stents for post-thrombotic syndrome (PTS) with iliac vein compression. Patients and methods: In the multinational, prospective, single-arm TOPOS study, PTS patients scheduled for endovascular therapy with the sinus-Obliquus® stent and optional distal extension with the sinus-Venous® or sinus-XL Flex® stent were enrolled at eight European vascular centres between October 2016 and December 2020. The primary outcome was primary stent patency at 24 months, and secondary outcomes included the clinical course of PTS (Villalta score, revised Venous Clinical Severity Score [rVCSS], Visual Analog Scale [VAS] of pain), quality of life changes (Chronic Venous Insufficiency Quality of Life Questionnaire, CIVIQ-20), and device-related complications. Results: We enrolled 60 patients (mean age 46±15 years, 68% women, 13% active ulcers): 80% required stent extension (70% below the inguinal ligament). The primary patency rate at 24 months was 80.7% (95%CI 68.1-90.0%); it was higher in patients without vs. those with stent extension (90.9% vs. 78.3%, p=.01). Compared to baseline, the Villalta, rVCSS, pain VAS, and CIVIQ-20 decreased by a median of 8 (interquartile range (IQR): 4-11), 5 (IQR: 3-7), 3 (IQR: 2-5), and 17 (IQR: 6-22) points, respectively; p<.001 for all parameters. Overall, 9 events of acute stent occlusion, 4 symptomatic stent stenosis, and 1 pulmonary embolism occurred. We did not observe major bleeding events or contralateral thrombosis. Conclusions: Endovascular treatment with the oblique stent and optional stent extension was safe and resulted in high patency rates at 24 months. The reduction in PTS severity was substantial and persisted over 2-year follow-up.

[Cockett's syndrome, a rare differential diagnosis of unilateral inferior member oedema]. / L'image du mois. Un diagnostic différentiel rare de l'œdème de membre inférieur unilatéral : le syndrome de Cockett.

We present here a typical picture of May-Thurner syndrome, rare but treatable etiology with specific treatment, of unilateral leg oedema and thromboembolic disease of the young woman.

Nous présentons ici une image typique de syndrome de Cockett, étiologie rare mais curable par un traitement spécifique, d'œdème de membre inférieur et de maladie thrombo-embolique chez la femme jeune.

[Successful endovascular treatment of proximal deep vein thrombosis following May-Thurner syndrome]. / Uspeshnoe lechenie proksimal'nogo tromboza glubokikh ven nizhnikh konechnostei na fone sindroma Meya-Ternera endovaskulyarnymi tekhnologiyami.

We present two clinical cases of successful endovascular treatment of proximal deep vein thrombosis following May-Thurner syndrome. In the first case, 2-day regional catheter thrombolysis, percutaneous mechanical thrombectomy and venous stenting were required to restore hemodynamics in the left lower limb. In the second case, regional catheter thrombolysis continued for 3 days with subsequent thrombotic mass lysis. However, iliac vein was severely narrowed that required venous stenting. Long-term results were favorable in both cases. Venous outflow has become almost normal after endovascular treatment. The patients' ability to work has been restored.

Rustrela Virus as Putative Cause of Nonsuppurative Meningoencephalitis in Lions.

Retrospective investigation of archived tissue samples from 3 lions displaying nonsuppurative meningoencephalitis and vasculitis led to the detection of rustrela virus (RusV). We confirmed RusV antigen and RNA in cortical neurons, axons, astrocytes and Purkinje cells by reverse transcription quantitative PCR, immunohistochemistry, and in situ hybridization.

Natural rubber reduces herbivory and alters the microbiome below ground.

Laticifers are hypothesized to mediate both plant-herbivore and plant-microbe interactions. However, there is little evidence for this dual function. We investigated whether the major constituent of natural rubber, cis-1,4-polyisoprene, a phylogenetically widespread and economically important latex polymer, alters plant resistance and the root microbiome of the Russian dandelion (Taraxacum koksaghyz) under attack of a root herbivore, the larva of the May cockchafer (Melolontha melolontha). Rubber-depleted transgenic plants lost more shoot and root biomass upon herbivory than normal rubber content near-isogenic lines. Melolontha melolontha preferred to feed on artificial diet supplemented with rubber-depleted rather than normal rubber content latex. Likewise, adding purified cis-1,4-polyisoprene in ecologically relevant concentrations to diet deterred larval feeding and reduced larval weight gain. Metagenomics and metabarcoding revealed that abolishing biosynthesis of natural rubber alters the structure but not the diversity of the rhizosphere and root microbiota (ecto- and endophytes) and that these changes depended on M. melolontha damage. However, the assumption that rubber reduces microbial colonization or pathogen load is contradicted by four lines of evidence. Taken together, our data demonstrate that natural rubber biosynthesis reduces herbivory and alters the plant microbiota, which highlights the role of plant-specialized metabolites and secretory structures in shaping multitrophic interactions.

The Pulsating Stent Sign in May-Thurner Syndrome.

PURPOSE: To report a case of a patient with May-Thurner syndrome who underwent endovenous stenting and was found to have pulsating arterial compression on the venous stent. REPORT: A 74-year-old man presented with 18 months of progressive right thigh and calf edema. After an extensive work-up, the patient underwent a venogram with intravascular ultrasound (IVUS), revealing compression of the right iliac vein by the external iliac artery and psoas muscle. Following stent deployment, fluoroscopy revealed extrinsic compression by an artery, but IVUS confirmed sufficient stent expansion. On follow-up, there was a significant resolution of right limb edema, and adjacent arterial pulsation/compression was deemed non-significant. CONCLUSION: The choice of venous stents is essential to prevent collapse from extrinsic compression, such as that from an adjacent artery. CLINICAL IMPACT: Carefully choosing venous stents is essential to ensure stent patency in the face of external compression.

Iliac vein recanalisation and stenting accelerate healing of venous leg ulcers associated with severe venous outflow obstruction.

Obstruction involving the iliac veins and/or inferior vena cava is highly comorbid in patients with chronic venous leg ulcers and is a barrier to healing. Intervention with venous stenting is recommended to promote wound healing; however, there is limited data to quantify the effects of venous outflow restoration on wound healing. We retrospectively identified patients with venous ulcers and comorbid venous outflow obstruction. Data regarding demographics, wound size, degree of obstruction, interventions, wound healing and recurrence were collected. Intervention was performed when possible and patients were grouped based on whether or not the venous outflow was reopened successfully and maintained for at least 1 year. Outcomes, including time to wound healing, wound recurrence, stent patency and ulcer-free time, were measured. Patients who maintained a patent venous outflow tract experienced higher rates of wound healing (79.3%) compared to those with persistent outflow obstruction (22.6%) at 12 months (p < 0.001). Ulcer-free time for the first year was also greater with patent venous outflow (7.6 ± 4.4 months versus 1.8 ± 3.0 months, p < 0.0025). Patients with severe obstruction of the venous outflow tract experience poor healing of VLUs despite appropriate wound care. Healing time is improved and ulcer-free time increased after venous intervention with stenting to eliminate obstruction.

Editor's Choice - Quality of Life after Stenting for Iliofemoral Venous Obstruction: A Randomised Controlled Trial with One Year Follow Up.

OBJECTIVE: Deep venous obstruction (DVO) is a great burden on the healthcare system and patients' quality of life (QoL). Case series show stenting is safe and effective, however most studies lack control groups and QoL changes have not been compared with conventional treatment. The aim was to assess the difference in QoL changes from baseline to 12 months between stent and conventionally treated patients with DVO. METHODS: Subjects > 18 years old with DVO due to post-thrombotic (PTS) or non-thrombotic iliac vein lesions (NIVLs) in a tertiary hospital were prospectively randomised to best medical therapy (BMT) or stent placement with BMT in a ratio 2:1, stratified for PTS or NIVL. The primary outcome was the between group difference in VEINES-QoL scores change from baseline to 12 months after treatment. Secondary outcomes included the difference in score changes for EuroQoL 5-Dimension 5 Level (EQ-5D-5L), Pain Disability Index (PDI), Venous Clinical Severity Score (VCSS), and the Villalta score. RESULTS: After three years, the inclusion rate dropped to almost zero, therefore the study had to be stopped. Sixty-three patients were randomised to either the stent (n = 42) or control group (n = 21). Overall, 50 patients had available data for primary outcome analysis. The adjusted mean difference between 12 month scores for VEINES-QoL and VEINES-Sym was 8.07 (95% CI 3.04 - 13.09) and 5.99 (95% CI 0.75 - 11.24) (p = .026), respectively, in favour of the stent group. The differences were significant, but a pre-defined meaningful 14 point improvement in QoL was not reached. The mean difference between 12 month scores for VCSS was -2.93 (95% CI -5.71 - 0.16, p = .040), -11.83 (95% CI -20.81 - 2.86, p = .011) for PDI, 0.015 (95% CI -0.12 - 0.15, p = .82) for the EQ-5D index, and -2.99 (95% CI -7.28 - 1.30, p = .17) for the Villalta score. CONCLUSION: Symptomatic patients with DVO who received dedicated venous stents had significantly higher VEINES-QoL/Sym scores at 12 months compared with the control group, but the between group difference was lower than the pre-specified clinically relevant QoL difference of at least 14 points. STUDY REGISTRATION NUMBER: NCT03026049.

Predictive Factors of Stent Patency in Iliofemoral Venous Diseases in a Multicentre Cohort Study.

OBJECTIVE: This study assessed primary stent patency predictive factors in three groups of patients with history of lower limb (LL) vein thrombosis: non-thrombotic iliac vein lesion (NIVL), acute deep vein thrombosis (aDVT), and post-thrombotic syndrome (PTS). METHODS: Consecutive patients from January 2014 to December 2020 with history of LL vein stenting from seven hospitals were included. All patients received an iliac or common femoral venous stent and had at least a six month follow up available with stent imaging. Anticoagulant and antiplatelet therapy strategies employed after venous stenting are reported and compared between groups. RESULTS: This study included 377 patients: 134 NIVL, 55 aDVT, and 188 PTS. Primary patency was statistically significantly higher in the NIVL group (99.3%) compared with the PTS group (68.6%) (p < .001) and the aDVT group (83.6%) (p = .002). PTS patients received a statistically significantly greater number of stents (p < .001) and had more stents below the inguinal ligament (p < .001). Median follow up was 28.8 months (IQR 16, 47). Discontinuation of antiplatelet therapy at the last assessment was 83.6% for NIVL, 100% for aDVT, and 95.7% for the PTS group (p < .001). Discontinuation of anticoagulation therapy at the last assessment was 93.2% for NIVL, 25.0% for aDVT, and 70.3% for the PTS group (p < .001). The only predictor of worse primary patency in the aDVT group was long term anticoagulation before stenting. CONCLUSION: Patients with NIVL have better primary patency after venous stenting than patients with venous thrombotic disorders. Long term anticoagulation before stenting was the only factor associated with poorer primary patency in patients with aDVT.

Spontaneous iliac vein rupture and thrombosis in patients with May-Thurner syndrome: A narrative review.

Spontaneous iliac vein rupture (SIVR) is extremely rare and can lead to serious complications, including death. Etiologies include inflammatory processes and hormonal and mechanical triggers, with concomitant May-Thurner syndrome (MTS) being a rare cause. Management can be challenging due to the difficult balance between reducing thrombotic burden and life-threatening hemorrhage that can result from aggressive anticoagulation. Furthermore, surgical interventions are associated with high mortality, making conservative management more desirable. We report a case of SIVR with retroperitoneal hematoma and concurrent MTS that was successfully managed using conservative measures. We further provide a narrative review of the current literature addressing the diagnosis, management, and outcome of SIVR focusing on cases with concurrent MTS.

Venous anomalies and thromboembolism.

Patients with venous anomalies are at increased risk of developing venous thromboembolism (VTE) and subsequent complications, but they are often under-recognised. While unprovoked VTE may trigger testing for inherited thrombophilias and malignancy screening, anatomic variants are considered less often. Venous anomalies increase the risk due to venous flow disturbance, resulting in hypertension, reduced flow velocity and turbulence. Recognition is important as endovascular or surgical intervention may be appropriate, these patients have a high rate of VTE recurrence if anticoagulation is ceased, and the anomalies can predispose to extensive VTE and severe post-thrombotic syndrome (PTS). In this case series, we present representative cases and radiological images of May-Thurner syndrome (MTS), inferior vena cava (IVC) variants and venous aneurysms, and review the available literature regarding optimal diagnosis and management in each condition.

Acute left iliofemoral vein thrombosis: Comparison between simple and bony May-Thurner syndrome in CT venography.

OBJECTIVES: To explore the etiology of May-Thurner syndrome (MTS) with acute iliofemoral deep vein thrombosis (DVT) regarding imaging findings and clinical features. METHODS: We retrospectively analyzed 57 patients with acute left iliofemoral DVT from 2015 to 2020. The diameter of left common iliac vein (LCIV) at the maximal compression site and its percent compression regarding the average diameter of the uncompressed iliac vein were recorded in central and distal portions of the LCIV according to the location in the quadrant of lumbar vertebral body. Compression was categorized into simple and bony MTS; Simple MTS as LCIV compressed by the right common iliac artery (RCIA) versus Bony MTS as LCIV by lower lumbar degenerative changes regardless of RCIA compression. Initial computed tomographic venography (CTV) regarding chronic change of LCIV such as fibrotic atrophy or cordlike obliteration, extent of thrombus, and lumbar degenerative changes were evaluated. Therapeutic effect after initial therapy was assessed in follow-up CTVs after 3-6 months. RESULTS: All patients showed LCIV compression with 19 simple MTS (mean age, 42.8 ± 14.1 years [23-67 years]; 12 females; symptom for 4.4 ± 5.5 days) and 38 bony MTS (mean age, 73.0 ± 10.2 years [49-85 years]; 26 females; symptom for 5.5 ± 4.8 days). There was significant difference in age (p < .001) and no significant difference in sex or symptom duration between two groups (p = .691 and 0.415, respectively). All simple MTS showed compression only in the central LCIV and half of bony MTS showed compression in both central and distal LCIV (p < .001). Among the lumbar degenerative changes, symmetric anterolateral osteophyte (p < .001) and asymmetric osteophyte (p < .001) were significantly associated with bony MTS, but not scoliosis (p = .799), compared to simple MTS. Although there was no significant difference in chronic change of LCIV, thrombosis extent, and therapeutic effect between two groups (p > .05), chronic change of LCIV showed significant difference between single and dual compression (23.7% vs. 57.9%, p = .024) and residual thrombus after initial therapy was occurred in 21.1% of single compression and 47.4% in dual compression with non-significant trend (p = .082). CONCLUSION: Bony MTS related to lumbar degenerative changes with acute iliofemoral DVT occurs in older patients, presenting more than one stenosis at LCIV, inducing more chronic change with possibly weaker therapeutic effect than simple MTS.

Evolution of Antenatally Diagnosed Bronchogenic Cyst in an Infant.

Bronchogenic cyst is one of the rare developmental lung conditions. Depending on the location, it can cause significant compression of the mediastinal structures, especially airways leading to atelectasis, emphysema, wheezing, and stridor. Computerized tomography helps in the confirmation of diagnosis. Surgery is definitive management. We present a case of bronchogenic cyst which presented as emphysema leading to respiratory emergency in an infant.

Deep venous thrombosis of the contralateral iliac vein after stenting of the iliocaval confluence: a therapeutic challenge.

The treatment of choice for patients with symptomatic venous compression syndrome is venous stenting. However, this treatment has well-documented complications and, although rare, contralateral deep venous thrombosis is one of these complications. Our objective is to present a case of deep venous thrombosis of the contralateral iliac vein resulting from placement of the stent beyond the recommended position and the therapeutic challenge is to recanalize the vein with reconstruction of the iliocaval confluence.

Combination between Dunbar Syndrome and May-Thurner Syndrome: A Rare Case Report.

Dunbar syndrome (DS) and May-Thurner syndrome (MTS) are part of a group of rare vascular disorders known as "vascular compression syndromes." Dunbar's syndrome is caused by the median arcuate ligament of diaphragm, which, due to an abnormal course, causes celiac artery compression. MTS is caused by the left common iliac vein compression pushed against the spine by the right common iliac artery causing progressive flow congestion and leading to thrombosis. Ultrasound is the first-level examination for the diagnosis of these rare pathologies and allows to recognize vascular compressions and to obtain an estimate of stenosis degree. We describe a very rare case of DS and MTS combination in a young man with postprandial pain and left lower limb thrombosis.

Mycobacterium lepromatosis as Cause of Leprosy, Colombia.

Leprosy is a granulomatous infection caused by infection with Mycobacterium leprae or M. lepromatosis. We evaluated skin biopsy and slit skin smear samples from 92 leprosy patients in Colombia by quantitative PCR. Five (5.4%) patients tested positive for M. lepromatosis, providing evidence of the presence of this pathogen in Colombia.