BackgroundMay-Thurner syndrome (MTS) is an anatomical anomaly characterized by compression of the left common iliac vein (LCIV) by the right common iliac artery (RCIA) presenting with left lower extremity swelling and venous hypertension. Persistent symptoms after MTS treatment often lead to referral for lymphedema workup to explore non-venous causes. We aimed to describe the presentation of MTS and the findings from the lymphedema workup.MethodsA retrospective review was conducted of patients with MTS and lower extremity lymphedema workup between 2013 and 2022 at a public academic hospital. Demographic data, diagnostic information, treatment details, and outcomes were collected. Descriptive statistical analysis was performed.ResultsOf 523 patients identified, 390(75%) were female, 133(25%) male with a mean BMI of 29.6 kg/m2. Mean age at diagnosis and symptom onset was 54.9(±17.1) and 47.6 (±18.2 )years, respectively. 465 patients (89%) were treated operatively with a combination of stenting, venoplasty, and thrombolysis while 47 (9%) were managed conservatively with compression garments and/or anticoagulation only. The LCIV was most commonly affected, followed by the left external iliac vein. The predominant symptoms were lower extremity deep vein thrombosis in 341 (65%) patients, lower limb edema in 286 (54%), and varicose veins in 129 (24.6%). Of six patients with lymphedema workup, three(50%) showed asymmetric or delayed uptake on lymphoscintigraphy and the remaining three had normal studies.ConclusionIn our study, May-Thurner syndrome was an uncommon but significant cause of lower extremity swelling and venous thromboembolism, especially in middle-aged females. Patients with persistent symptoms after intervention may benefit from diagnostic workup for lymphedema and treatment. More research is needed on the co-occurrence of lymphedema with MTS and its pathophysiology.

Total knee arthroplasty (TKA) can cause significant hidden blood loss after surgery, and transfusion or erythropoietin (EPO) treatment may be required. This study aimed to identify the factors associated with blood loss in patients undergoing TKA for osteoarthritis (OA).

We retrospectively enrolled 1444 OA patients undergoing primary TKA from January 2022 to June 2024. The patients were divided into two groups according to the grade of hidden blood loss. To identify the key influencing factors, we conducted a logistic regression analysis.

This study analyzed 1,444 primary arthroplasty cases, identifying 236 patients with high hidden blood loss (HHBL). Coronary artery disease (CAD) was significantly more prevalent in the HHBL group (15.3% vs. 9.4%, p = 0.006). Preoperative EPO use was higher in the low hidden blood loss (LHBL) group (21.9% vs. 9.3%, p < 0.001). Significant preoperative lab differences included hemoglobin, hematocrit, and platelet count. Surgical factors associated with HHBL included left knee TKA, conventional mechanical TKA (CMTKA), longer operation times, and intraoperative blood loss (IBL) > 20%. Postoperatively, the HHBL group had significantly more transfusions and longer hospital stays. Logistic regression identified CAD, platelet count, left knee surgery, CMTKA, operation time, and preoperative EPO use as significant factors influencing HHBL. These findings highlight the need for targeted strategies to manage blood loss in knee arthroplasty patients.

This study identifies several factors associated with high hidden blood loss in patients undergoing TKA for osteoarthritis. CAD, CMTKA, prolonged operation time, left-sided surgery, lower preoperative platelet count, and lack of preoperative erythropoietin (EPO) use were significantly linked to HHBL. While these associations highlight potential targets for intervention, further prospective studies are needed to confirm causality.

The purpose of this study was to explore the characteristics of hemodynamic parameters of iliac vein of patients with chronic venous disease (CVD) using two-dimensional (2D)-phase contrasted (PC) and four-dimensional (4D)-Flow magnetic resonance imaging (MRI) and to test the diagnostic and grading efficiency of 2D-PC and 4D-Flow MRI in CVD and iliac vein compression syndrome (IVCS).

Consecutive patients with CVD diagnosed in the outpatient department from 2023 to 2024 were enrolled in this study. Demographic data and medical records of the patients were also collected. The CEAP classification, Villalta score, and Venous Clinical Severity Score (VCSS) were used to evaluate the severity of lower limb symptoms. After computational tomography venography (CTV) scans to verify iliac vein compression, every patient underwent 2D-PC and 4D-Flow MRI scanning. Circle CVI42 software was used to perform data post processing. The inferior vena cava (IVC), common iliac vein (CIV), and common femoral vein (CFV) were chosen to acquire hemodynamic parameters by MRI. The hemodynamic parameter included flow rate (FR) per cardiac cycle, FR per minute, peak flow velocity (FV) and minimum FV measured by 2D-PC MRI and FR per cardiac cycle, peak FV and pressure gradient measured by 4D-Flow MRI. We analyzed the consistency of hemodynamic parameters between 2D-PC and 4D-Flow MRI, the differences in hemodynamic parameters between symptomatic and asymptomatic limbs and limbs with and without iliac vein compression, and the correlation between parameters and severity of symptoms.

A total of 34 individuals, including three healthy volunteers, 15 patients with CVD and iliac vein compression, and 16 patients with CVD without IVCS, were enrolled in this study. Hemodynamic parameters measured by 2D-PC and 4D-Flow MRI complied with the flow rate conservation and maintained consistency (P < .01). There was a statistically significant difference in the FR of the CIV and FR difference between the CIV and CFV measured by 2D-PC and 4D-Flow MRI between symptomatic and asymptomatic limbs (2D-PC MRI: FR of CIV: 6.0 ± 3.1 vs 8.5 ± 5.1; P = .01; FR difference: 1.6 ± 2.1 vs 3.6 ± 4.3; P = .01) (4D-Flow MRI: FR of CIV: 6.9 ± 2.8 vs 8.7 ± 4.2; P = .04; FR difference: 3.0 ± 2.8 vs 4.8 ± 3.5; P = .05), and limbs with and without iliac vein compression (2D-PC MRI: FR of CIV: 5.3 ± 3.0 vs 7.6 ± 4.4; P = .03; FR difference: 1.3 ± 2.7 vs 2.8 ± 3.4; P = .04) (4D-Flow MRI FR of CIV: 6.1 ± 2.6 vs 8.2 ± 3.7; P < .01; FR difference: 2.1 ± 3.7 vs 4.6 ± 3.1; P = .04). The FR of the CIV and the FR difference between the CIV and CFV were negatively correlated with symptom severity in all affected limbs (2D-PC MRI: FR of CIV: P < .01; r = -0.3; FR difference: P = .03; r = -0.3). There was a potential negative correlation between the FR of the CIV in limbs with iliac vein compression and the severity of symptoms (2D-PC MRI: FR of CIV: P = .07; r = -0.4).

In conclusion, hemodynamic parameters provided by 2D-PC and 4D-Flow MRI possess the potential clinical value of evaluating CVD and iliac vein compression.

Chronic venous insufficiency (CVI) is a prevalent disorder, arising from venous valve incompetence and vein wall weakness, which impairs blood return and leads to venous stasis and hypertension in the lower extremities. This condition, affecting up to 40% of older adults, has been primarily considered a peripheral issue. However, growing evidence indicates its systemic impacts, notably its contribution to cardiovascular dysfunction and heart failure (HF). CVI exacerbates central venous pressure and cardiac preload, placing strain on the right heart and predisposing at-risk patients to HF. Moreover, a feedback loop exists where HF worsens CVI through increased venous stasis and fluid overload, highlighting a complex bidirectional relationship. Emerging research reveals that CVI-driven inflammation and endothelial dysfunction may accelerate adverse cardiac dysfunction. This review provides a comprehensive analysis of CVI's systemic effects, emphasizing the need for integrated cardiovascular and venous management strategies to address the reciprocal influences of CVI and HF. Such an approach could reduce disease progression and enhance outcomes for affected patients.

To compare the sensitivity of measuring iliac vein stenosis using two-dimensional digital subtraction angiography (2D-DSA) and three-dimensional digital subtraction angiography (3D-DSA), with multidetector computed tomography venography (MDCTV) as the reference standard.

Between January 2020 and January 2023, a total of 103 patients suffered from chronic venous insufficiency symptoms categorized as CEAP Level 3 or above were included from three centers. These patients were admitted to our hospital after abdominal vascular ultrasound and MDCTV positivity. During hospitalization, all patients underwent both 2D-DSA and 3D-DSA procedures simultaneously. Ensure double-blind and rigorous evaluation process when evaluating images. All patients were categorized into two groups based on the degree of CTV stenosis: Group A (50%-70%) and Group B (>70%). Considering the morphology of iliac vein compression, all patients were categorized into three groups: central, lateral, and partial obstruction. Subsequently, the effectiveness analysis was performed for each diagnostic method based on the aforementioned classification.

With MDCTV as the reference standard, in Group A, the sensitivity of 2D-DSA and 3D-DSA is 78.69% and 90.48%, respectively. In Group B, the sensitivity of 2D-DSA and 3D-DSA is 93.44% and 97.62%, respectively. In Group A, the accuracy of 3D-DSA is significantly higher than that of 2D-DSA (p = 0.019). However, there is no statistically significant difference in Group B (p = 0.360). The accuracy rates for central, lateral, and partial obstruction using 2D-DSA are, respectively, 77.55%, 69.70%, and 95.24%. The accuracy rates for central, lateral, and partial obstruction using 3D-DSA are, respectively, 93.88%, 93.94%, and 100%. In central group, the accuracy of 3D-DSA is significantly higher than that of 2D-DSA (p = 0.021). In lateral group, no significant difference was observed between the accuracy obtained by both methods (p = 0.011). Similarly, no significant difference was found in partial obstruction group (p = 1.000). During the angiography procedure using 3D-DSA, a significant reduction was observed in both contrast agent quantity and exposure time (p < 0.05) without any apparent effects on renal function.

Regardless of the degree or type of iliac vein stenosis, 3D-DSA exhibits superior sensitivity compared to 2D-DSA for the diagnosis and evaluation of stenosis. Particularly in instances of noncentral stenosis, 3D-DSA outperforms 2D-DSA.Clinical ImpactThis will provide new insights for the clinical diagnosis and treatment of iliac vein compression syndrome (IVCS), significantly enhancing the diagnostic accuracy of IVCS. For clinicians, three-dimensional digital subtraction angiography (3D-DSA)offers a more comprehensive and detailed assessment in clinical practice, leading to more precise diagnosis and treatment of the disease. The efficacy of two-dimensional digital subtraction angiography (2D-DSA) in treating IVCS is significantly compromised without the guidance from computed tomography venography (CTV). We consider that 3D-DSA can replace CTV in both diagnosis and treatment, providing a new diagnostic and therapeutic strategy.

May-Thurner syndrome (MTS), iliac vein compression syndrome, also called Cockett syndrome, is a vascular disease caused by the compression of the left common iliac vein (LCIV) by the right common iliac artery (RCIA) against the lumbar vertebrae. This anatomical defect can lead to venous stasis especially in the left lower limb, and this increases the risk of deep venous thrombosis (DVT). Because routine screening is not standard practice, MTS frequently remains asymptomatic, and its prevalence is probably underestimated. Our case report presents 33 year old women with no thrombotic condition history who complained from a left leg swelling, pain, and stiffness over 5 days. Computed tomography angiography (CTA) confirmed a diagnosis of MTS, and Doppler ultrasonography confirmed extensive DVT in the left lower limb. After receiving conservative treatment with enoxaparin, the patient switched to apixaban therapy. The significance of identifying MTS as a possible cause of unilateral left-sided DVT is highlighted by this case, especially in young, otherwise healthy women. Recurrent DVT and chronic venous insufficiency are among the complications that can be prevented by early detection with imaging and anticoagulation treatment. Patients with atypical DVT presentations may benefit from earlier diagnosis and treatment made possible by greater knowledge of MTS.

The present study assessed the effectiveness and safety of stent placement for treating iliac vein compression syndrome (IVCS) with acute deep venous thrombosis (DVT).

We conducted a retrospective study on 31 patients with IVCS companied with acute DVT who underwent percutaneous mechanical thrombectomy or catheter-directed thrombolysis and angioplasty combined with iliac vein stenting from January 2017 to January 2023. Follow-up was performed at 3, 6, and 12 months after the surgical procedure. At each visit, patients were evaluated by colour Doppler ultrasound or computed tomography venography to determine stent patency; additionally, visual analog scale (VAS), venous clinical severity score (VCSS), and five-level EuroQol-five dimensions (EQ-5D-5L) questionnaire were used to assess pain, severity, and symptoms associated with venous pathology and quality of life, respectively.

The technical success rate of stent placement was 100 % in all patients. All patients completed follow-up at 3, 6, and 12 months after surgery. The primary patency rates were 96.8 % (95 % CI: 90.2-103.4 %) at 3, 6, and 12 months. The secondary patency rate was 96.8 % (95 % CI: 90.2-103.4 %) at 3 months and 100 % at 6, and 12 months. Only one patient experienced in-stent restenosis and underwent reintervention postoperation. All patients showed a significant improvement (P<0.05) in the scores of VAS, VCSS, and EQ-5D-5L.

Venous stent implantation was a safe and effective therapeutic approach for patients with IVCS combined with acute DVT.

 To investigate the efficacy of balloon dilatation combined with stent implantation in the treatment of iliac vein compression syndrome (IVCS).

 This research was a retrospective study that enrolled 127 IVCS patients for clinical data. The patients were divided into percutaneous transluminal angioplasty (PTA) group (n = 63) and stent implantation group (n = 64). The PTA group was treated with iliac vein balloon dilatation, and the stent implantation group was treated with combined stent implantation based on the PTA group. In both the groups, the quality of life was assessed using Chronic Venous Insufficiency Quality of Life Questionnaire (CIVIQ); complications occurring during the perioperative period and at postoperative follow-up were recorded; the vascular patency rate was calculated, and patient's condition was evaluated using the Villalta scale.

 The stent implantation group exhibited lower postoperative CIVIQ scores than the PTA group, and the stent implantation group (4.60%) had lower complication rate than the PTA group (19.05%). At 2 years of follow-up, the stent implantation group (92.19%) had higher vascular patency rate than the PTA group (79.37%). Villalta scores were lower in the stent implantation group than in the PTA group at 6, 12, and 24 months postoperatively.

 Iliac vein balloon dilatation combined with stent implantation for the treatment of IVCS can improve vessel patency rates, alleviate patients' clinical symptoms, and enhance their quality of life.

May-Thurner syndrome, also known as external iliac compression syndrome, is a rare but commonly underdiagnosed cause of asymmetric lower extremity edema. Here we describe a case of May-Thurner syndrome owing to external compression of the right and left common iliac veins presenting as chronic worsening asymmetric right greater than left lower extremity edema. Initial etiology workup was unremarkable, and further diagnostics revealed compression of the right common iliac vein at the bifurcation of the right common iliac artery between the right external and internal iliac arteries with concomitant compression of the left common iliac vein. Stenting of the right common iliac vein was completed, with significant symptomatic improvement at 30-day follow-up. This case documents a unique variant of May-Thurner syndrome rarely described in the literature.

Iliac Vein Compression Syndrome (IVCS) is a common risk factor for deep vein thrombosis in the lower extremities. The objective of this study was to investigate whether employing a porous medium model to simulate the compressed region of an iliac vein could improve the reliability and accuracy of Computational Fluid Dynamics (CFD) analysis outcomes of IVCS. Pre-operative Computed Tomography (CT) scan images of patients with IVCS were utilized to reconstruct models illustrating both the compression and collateral circulation of the iliac vein. A porous medium model was employed to simulate the compressed region of the iliac vein. The agreements of times to peak between discrete phase particles in CFD analysis and contrast agent particles in Digital Subtraction Angiography (DSA) were compared. Furthermore, comparisons were made between the CFD analysis results that incorporated the porous media and those that did not. The results revealed that in the CFD analysis incorporating the porous media model, more than 80% of discrete phase particles reached the inferior vena cava via collateral circulation. Additionally, the concentration variation curve of discrete phase particles demonstrated a high concordance rate of 92.4% compared to that obtained in DSA. In comparison to CFD analysis conducted without the porous medium model, the incorporation of the porous medium model resulted in a substantial decrease in blood flow velocity by 87.5% within the compressed region, a significant increase in pressure gradient of 141 Pa between the inferior vena cava and left iliac vein, and a wider distribution of wall shear stress exceeding 2.0 Pa in collateral vessels rather than in the compressed region. The study suggests that the introduction of a porous medium model improves the hemodynamic analysis of patients with IVCS, resulting in a closer alignment with clinical observations. This provides a novel theoretical framework for the assessment and treatment of patients with IVCS.

To determine the structural changes of Wallstents (Boston Scientific, Natick, MA) in vivo following deployment in iliac veins.

This retrospective single-center study was performed from September 2012 to April 2013 and included 100 office-based patients who underwent initial stent placement for nonthrombotic iliac vein lesions with Wallstent as well as a second procedure for stenting of the contralateral iliac vein. Measurements were obtained with marker balloons and the diameters of the stents were compared at the time of the index procedure to the secondary procedure.

The average time between the 2 procedures was 28 days (range 3-237, SD ± 39.89). The overall average stent diameter after the index procedure was 16.38 mm (range 10.95-21.45, SD ± 2.24). The overall average stent diameter of the index stent when remeasured during the second intervention was 17.58 mm (range 12.84-24.11, SD ± 2.38, P = 0.0003), which was significantly different from the initial measurements. There was no difference when comparing changes in stent diameter by gender or laterality of procedure. However, there was a significant difference in expansion of stents when placed in the common iliac vein versus the external iliac or common femoral veins.

This study shows that self-expanding Wallstents can continue to expand days to weeks in vivo following initial deployment. Additionally, we found that the change in diameter from initial placement to follow-up was more significant in stents placed in the proximal and middle segments of the common iliac vein.

Wallstents are durable implants designed to last within a patient for the rest of their life, it is important to understand the structural changes occurring after their placement. This study allows for a better understanding of Wallstent dynamics in vivo.

Venous Clinical Severity Score (VCSS) is a widely used standard for assessing and grading the severity of chronic venous disease (CVD). Prior research highlighted its high validity in detecting and quantifying venous disease. However, there is little, if any, known about the precise thresholds at which VCSS discriminates important stages of deep venous disease. This study sought to elucidate the diagnostic accuracy, thresholds, and correlation at which VCSS detects salient CEAP (Clinical-Etiology-Anatomy-Pathophysiology) classes in deep venous disease progression.

A registry of 840 patients who presented with chronic proximal venous outflow obstruction (PVOO) secondary to non-thrombotic iliac vein lesions from August 2011 to June 2021 was retrospectively analyzed. VCSS and CEAP classifications were used to evaluate preoperative symptoms. VCSS was compared to CEAP classes to determine the precise VCSS composite values at which the instrument was able to detect CEAP C3 and higher, C4 and higher, and C5 and higher. Receiver operative characteristic (ROC) curve and area under the curve (AUC) were used to evaluate VCSS for its ability to discriminate disease at these stages of CEAP classification. Spearman's rank coefficient was used to determine the correlation between CEAP VCSS composite as well as individual VCSS components (pain, varicose vein, edema, pigmentation, inflammation, induration, ulcer number, ulcer size, ulcer duration, compression).

VCSS composite was able to detect venous edema (C3) and higher at a sensitivity of 68.9% and a specificity of 54.8% at an optimized threshold of 8.5 (AUC = 0.648; 95% C.I. = 0.575-0.721). To detect changes in skin and subcutaneous tissue from CVD (C4) and higher, an optimal threshold of 11.5 was found with a sensitivity of 51.7% and specificity of 76.5% (AUC = 0.694; 95% C.I. = 0.656-0.731). Healed venous ulcer (C4) and higher was detectable at an optimized threshold of 13.5 at a sensitivity of 67.7% and a specificity of 88.9% (AUC = 0.819; 95% C.I. = 0.766-0.873). The correlation between VCSS composites and CEAP was weak (ρ = 0.372; p < .001). Attributes of VCSS that reflect more severe venous disease correlated more closely with CEAP classes, namely pigmentation (ρ = 0.444; p < .001), inflammation (ρ = 0.348; p < .001), induration (ρ = 0.352; p < .001), number of active ulcers (ρ = 0.497; p < .001), active ulcer size (ρ = 0.485; p < .001), and ulcer duration (ρ = 0.497; p < .001). The correlation between CEAP class and the other four components of VCSS were not statistically significant.

VCSS composite thresholds of 8.5, 11.5, and 13.5 are threshold values for detecting CEAP classification C3 and higher, C4 and higher, and C5 and higher, respectively. Consistent with prior work, VCSS appears to have a better ability to discriminate CVD at more severe CEAP classifications. In this registry, the correlation between VCSS and CEAP was found to be weak while components of VCSS that suggest more advanced disease exhibited the strongest correlation with CEAP.

May-Thurner syndrome is an anatomical anomaly characterized by venous compression of the iliac vein by the arterial system. It is more common in women. It may be asymptomatic or lead to symptoms related to hypertension/venous occlusion, namely, edema of the lower limb. The exact value of its prevalence is unknown. This case reports a 52-year-old woman with a personal history of cervical cancer. She went to her family doctor in June 2021 with complaints of edema of the left thigh, evolving over one week, without associated trauma or pain. She was directed to the emergency service, where after carrying out blood analysis, an indication for topical anti-inflammatories and monitoring of alarm signs was given. She went to the emergency service two more times in the next month with the same indications for treatment. In September 2022, during a family doctor's appointment, she again mentioned concerns regarding asymmetry of her legs. On objective examination, varicose veins were observed bilaterally. Blood analysis and arterial and venous echo-Doppler were required. There were no changes in the blood analysis. The echo-Doppler was not very conclusive, showing only slightly insufficient perforating veins. It was decided to request an abdominopelvic computed tomography (CT) whose result in February 2023 demonstrated extrinsic compression at the emergence of the left common iliac vein by the right iliac artery, likely related to May-Thurner syndrome. This clinical case recalls the importance of the family doctor in the longitudinal monitoring of his patients. The unique opportunity to learn about their background and evaluate them when surveying diagnostic hypotheses led to an unexpected diagnosis.

Orthostatic hypotension (OH) is a common cardiovascular disorder with high prevalence in the elderly. Concomitant venous return impairment may worsen the autonomic response and accentuate the symptoms. We detailed a patient with severe OH, prominent varicosities, and hemosiderin deposition in lower limbs. After excluding autonomic and neurological etiology, a computed tomography venography revealed significant common iliac vein compression. The patient was deemed to benefit from venous stenting. At a 2-year follow-up, the patient reported symptom improvement with adequate stent patency. Venous stenting may aid in the treatment of patients with severe OH symptoms without clear etiology and impairment of venous return.

Iliac vein compression syndrome (IVCS) is a clinical condition defined as obstruction of the iliac vein caused by chronic compression imposed by various causes. Currently, the clinical role of computed tomography venography (CTV) in the diagnosis of IVCS is unclear. Accurately diagnosing IVCS using CTV may enhance the understanding of the pathological anatomy of iliac veins, which may lead to better treatment outcomes, especially for recalcitrant venous leg ulcers (VLU). We aimed to investigate diagnostic criteria, contributing clinical factors, and stenting for IVCS with VLU in this study. CTV, digital subtraction angiography (DSV), and Doppler ultrasound (DUS) data were obtained from the medical and imaging records of 62 patients. Additionally, contributing factors and stenting for IVCS were analysed. Patients (100%) had clinical, aetiological, anatomic, or pathological C6 disease. CTV reduced the procedure time and contrast medium dose and provided more information than DSV. Risk factors for IVCS with VLU included female sex (P = 0.036) and advanced age (P = 0.014). The rate of ulcer healing was lower in the IVCS group without stent implantation (P = 0.020). Significant improvements were noted in venous clinical severity scores (P < 0.001) and chronic venous insufficiency questionnaire-20 scores (P < 0.001) after stenting for IVCS with C6 ulcers. CTV provides a more accurate diagnosis than DUS and DSV and allows detection of possible causes of IVCS. Female sex and advanced age were potential contributing factors for IVCS. Satisfactory outcomes were observed with stenting in the treatment of IVCS with C6 ulcers.

Deep vein thrombosis (DVT) is a serious condition with a high disease burden. Pulmonary embolism is one of the disastrous complications of DVT. The etiology of DVT includes factors responsible for hypercoagulation, venous injury, and factors causing stasis in the deep veins. May-Thurner syndrome (MTS) is one of the rarely thought of causes of DVT. MTS is an anatomical variant where the right common iliac artery compresses the left common iliac vein against the lumbar vertebrae. This leads to thrombus formation and stenosis in the left common iliac vein at the site of cross-over, resulting in an iliofemoral DVT. We present a case of a young female who presented with acute bilateral pulmonary embolism and subsequent cardiac arrest. She was treated with mechanical thrombectomy, angioplasty, and stent placement under the umbrella of anticoagulant agents. We aim to present this case to highlight that MTS should be considered a differential etiological condition in iliofemoral DVT. MTS is a rarely considered condition by clinicians while evaluating patients with lower limb DVT. When unaddressed, MTS can lead to recurrent DVT, post-thrombotic syndrome, and fatal complications like pulmonary embolism. Clinicians should investigate for possible MTS in patients with left lower extremity venous thrombotic events, irrespective of the presence of other risk factors.

May-Thurner syndrome (MTS) involves the chronic compression of the left common iliac vein (CIV) by the overlying right common iliac artery (CIA) against the lumbar vertebrae. This compression can result in signs and symptoms of deep vein thrombosis (DVT) affecting the left side. In this case report, we present the clinical details of a 19-year-old patient diagnosed with severe MTS, which manifested as DVT with symptoms of severe thigh pain, redness, and difficulty walking. Additionally, the patient experienced pleuritic chest pain, ultimately diagnosed as pulmonary embolism (PE). Her management involved surgical removal of the thrombus and endovascular stenting of the left CIV. Following her recovery, she progressed favorably, and her follow-up assessment yielded satisfactory results.

Abdominopelvic vascular compression syndromes (VCS) refer to conditions where blood vessels in the abdomen or pelvis are compressed by nearby structures, leading to various symptoms and complications. These conditions include superior mesenteric artery syndrome (SMAS), nutcracker syndrome (NCS), May-Thurner syndrome (MTS), and median arcuate ligament syndrome (MALS). Each syndrome is characterized by specific compressions of blood vessels, resulting in symptoms such as pain, nausea, vomiting, weight loss, leg swelling, and other related issues. Ehlers-Danlos syndrome (EDS), characterized by hyperelasticity, altered collagen, and mobility of the viscera, has been associated with VCS, although the exact prevalence is unknown. We report a case of a patient with EDS who presented with multiple VCS, including NCS, MTS, SMAS, and MALS.

May-Thurner syndrome (MTS) is a rare cause of deep venous thrombosis (DVT), characterized by the external compression of the left common iliac vein by the right common iliac artery against bony structures. Risk factors for MTS include female sex (postpartum, multiparous, and using oral contraceptive pills), spinal abnormalities like scoliosis, prior aortoiliac vascular stent placement, dehydration, and hypercoagulability. MTS patients with partial obstruction can be asymptomatic, but progression to extensive symptomatic DVT and/or chronic venous insufficiency can occur. MTS can be diagnosed by non-invasive imaging studies including ultrasound (US), computed tomography (CT) scan, magnetic resonance imaging (MRI), venogram, catheter-based venogram, and intravascular US. For MTS patients with moderate to severe symptoms, we suggest thrombectomy, angioplasty, and stenting of the affected segment. In this case report, we highlight a 44-year-old male with a recent diagnosis of left-sided DVT on apixaban who presented with worsening leg swelling. DVT, pulmonary embolism (PE), and MTS were diagnosed with a lower extremity US, chest CT angiography, and abdominal/pelvic CT scan and venography, respectively. The patient underwent interventional radiology-guided local thrombolysis, thrombectomy, and venoplasty along with stent placement in the left common iliac vein. Subsequently, the patient was discharged on rivaroxaban.

May-Thurner syndrome (MTS) is a pelvic venous disorder involving compression of the left common iliac vein by the right common iliac artery, which results in predisposition for deep vein thrombosis. Although MTS is increasingly recognized in young patients, specific guidelines on diagnosis and management for children, adolescents, and young adults do not exist so far. The aim of this study was to assess current diagnostic and therapeutic practice in Germany, Austria, and Switzerland in children and young adults with thrombosis and MTS.We designed an online survey with 11 questions, which we sent via a mailing list to all members of the German, Austrian, and Swiss Society of Thrombosis and Haemostasis Research. Between July and October 2022, 33 specialists answered the questionnaire. Most participating specialists worked at pediatric hospitals (61%). Numbers of annually treated thromboses ranged from <5 (26%) to >30 (13%). Most specialists used venous ultrasound to diagnose deep vein thrombosis, 53% magnetic resonance imaging. Only 25% of specialists systematically screened for MTS in deep vein thrombosis. MTS was managed with anticoagulation (65%), iliac vein stent placement (32%), or balloon angioplasty (13%). In total, 31% of specialists reported to use more than one therapeutic method. Diagnostic and therapeutic approaches for MTS differed between specialists. Lack of standardization resulted in individualized and highly diverse management. Prospective observational clinical studies investigating the outcome of different management strategies including long-term follow-up on outcome and incidence of postthrombotic syndrome will help in defining patient groups who benefit most from revascularizing interventional strategies and developing standardized guidelines.

Intraluminal anomalies within the left common iliac vein, characteristic of iliac vein compression syndrome, are thought to result from compression by and pulsation of the overlying right common iliac artery. This cadaver study was designed to expand on the existing literature by surveying and photographing these spurs in addition to exploring whether certain factors, inherent to the cadaver, are associated with spur presence.

Dissection to expose the aorta, inferior vena cava, and common iliac arteries and veins was performed in 51 cadavers. The spinal level at which the iliac vein confluence occurred was noted. The point at which the right common iliac artery crossed the left common iliac vein was examined for plaque presence. The overlying arterial structures were then transected to expose the venous system. The inferior vena cava was incised to facilitate observation into the mouth and full extent of the left common iliac vein. Spurs were photographed and documented. Statistical analysis was conducted to determine whether sex, body mass index (BMI), plaque presence, or level of the iliac vein confluence are associated with spur presence.

Spurs within the left common iliac vein were observed in 16 of 51 cadavers (31.4%). All spurs were located at the point that the right common iliac artery crossed the left common iliac vein. Using1 the classification system established by McMurrich, 67% of spurs (n = 10) were marginal and triangular; 25% (n = 4) were columnar. One marginal, linear spur (6%) and one partially obstructed spur with multiple synechiae (6%) were observed. Among this population, males were 73% less likely to have a spur (odds ratio, 0.269; P = .041). No significant relationship was found between plaque presence and spur presence (odds ratio, 0.933; P = .824) and no significant differences were noted between BMI and spur presence (χ2 = 1.752, P = .625). Last, a significantly greater percent of spurs was found within cadavers with an iliac vein confluence located at the L5/S1 disc space (χ2 = 9.650; P = .002).

Study findings show that spurs are more common when the confluence of the common iliac veins occurs at a lower spinal level. The level of the iliac vein confluence may be important in identifying patients at increased risk of venous disease. The findings also suggest that plaque within the right common iliac artery and BMI display no distinct relationship with spur presence. Further investigation is needed to understand exactly what factors lead to spur formation.

May-Thurner syndrome (MTS) is an extrinsic venous compression by the arterial system against bony structures in the iliocaval territory. The most common variant of MTS is due to compression of the left iliac vein between the overlying right common iliac artery and the fifth lumbar vertebrae. The prevalence of MTS is unknown; therefore, there are only a few publications about MTS in kidney transplant recipients. Risk factors that may progress from usually asymptomatic to symptomatic MTS are female sex, scoliosis, dehydration, coagulation disorders, and radiation. Clinical presentations include acute extremity pain and swelling, venous claudication, and chronic signs of venous insufficiency.

We describe a 63-year-old man who underwent kidney transplantation (left iliac fossa). Four days after transplantation, a graftectomy was done due to graft rupture caused by renal vein thrombosis. After imaging studies, a diagnosis of MTS was established. The patient had no typical symptoms of MTS. However, an incidence of right lower limb thrombosis was observed, and due to vertebral discopathy, the patient underwent surgery with implantation of a vertebral implant.

After a successful second transplantation on the right side, incidents of thrombosis were observed: superficial thrombosis of the upper limbs and massive deep vein thrombosis of the right lower limb. Thrombophilia was recognized, the graft function is stable, and anticoagulation therapy is being continued.

Asymptomatic MTS in the case of coincidence of other risk factors, such as coagulation disorders, history of vertebral operation, and additional pressure of the graft, can result in graft failure.

Venous thromboembolism significantly contributes to patient deterioration and mortality. Management of its etiology and anticoagulation treatment is intricate, necessitating a comprehensive consideration of various factors, including the bleeding risk, dosage, specific anticoagulant medications, and duration of therapy. Herein, a case of lower extremity thrombosis with multiple primary malignant tumors and high risk of bleeding was reviewed to summarize the shortcomings of treatment and prudent anticoagulation experience.

An 83-year-old female patient was admitted to the hospital due to a 2-wk history of left lower extremity edema that had worsened over 2 d. Considering her medical history and relevant post-admission investigations, it was determined that the development of left lower extremity venous thrombosis and pulmonary embolism in this case could be attributed to a combination of factors, including multiple primary malignant tumors, iliac venous compression syndrome, previous novel coronavirus infection, and inadequate treatment for prior thrombotic events. However, the selection of appropriate anticoagulant medications, determination of optimal drug dosages, and establishment of an appropriate duration of anticoagulation therapy were important because of concurrent thrombocytopenia, decreased quantitative fibrinogen levels, and renal insufficiency.

Anticoagulant prophylaxis should be promptly initiated in cases of high-risk thrombosis. Individualized anticoagulation therapy is required for complex thrombosis.

Deep venous thrombosis is a significant medical condition that results in life-threatening complications such as pulmonary embolism. Various factors can contribute to the formation of deep venous thrombosis, including prolonged immobility, surgery, and specific health conditions. May-Thurner syndrome is an underrecognized cause of deep venous thrombosis due to the compression of the left common iliac vein by the right common iliac artery. It poses diagnostic challenges due to its varied clinical presentations. This report discusses a 42-year-old female with no notable medical history who presented with acute onset of left leg swelling, pain, and discoloration. Despite the absence of common risk factors for deep venous thrombosis, investigations revealed a massive left-sided deep venous thrombosis. Additional imaging studies revealed the diagnosis of May-Thurner syndrome, manifesting as significant compression of the left common iliac vein. The patient underwent anticoagulation therapy, catheter-directed thrombolysis, and stent placement, resulting in symptomatic improvement and no recurrence over a six-month follow-up period. This case underscores the necessity of considering anatomical variations like May-Thurner syndrome in patients with unexplained deep venous thrombosis, particularly without typical risk factors. It highlights the importance of a comprehensive diagnostic approach, including advanced imaging techniques, to uncover underlying causes of deep venous thrombosis.

Diabetes, hypertension, and smoking are well-recognized risk factors for peripheral artery disease (PAD), but little is known of their impact on chronic venous insufficiency (CVI). This study evaluates these factors in patients undergoing iliac vein stenting (IVS) for CVI.

A registry of 708 patients who underwent IVS from August 2011 to June 2021 was retrospectively analyzed. Symptoms were quantified using venous clinical severity score (VCSS) and CEAP classification. Both major and minor reinterventions were recorded. Logistic regression models were used to determine the unadjusted and adjusted odds ratio of any reintervention. Log-rank test was used to assess differences in reintervention-free survival.

The prevalence of hypertension was 51.1% (N = 362), diabetes was 23.0% (N = 163), and smoking was 22.2% (N = 157). Patients with diabetes (3.6 vs. 3.4; P = 0.062), hypertension (3.6 vs. 3.3; P < 0.001), and smoking (3.7 vs. 3.4; P = 0.003) had higher CEAP scores than those without these comorbidities. Improvement in VCSS composite scores showed no differences postoperatively (diabetes: P = 0.513; hypertension: P = 0.053; smoking: P = 0.608), at 1-year follow-up (diabetes: P = 0.666; hypertension: P = 0.681; smoking: P = 0.745), or at 5-year follow-up (diabetes: P = 0.525; hypertension: P = 0.953; smoking: P = 0.146). Diabetes (P = 0.454), smoking (P = 0.355), and hypertension (P = 0.727) were not associated with increased odds of major reintervention. Log-rank test similarly showed no differences in reintervention-free survival for major or minor reoperations between those with and without diabetes (P = 0.79), hypertension (P = 0.14), and smoking (P = 0.80).

Diabetes, hypertension, and smoking were prevalent among CVI patients, but unlike in PAD patients, they had little to no impact on long-term outcomes or reinterventions after IVS.

Pelvic congestion syndrome (PCS) in females and varicoceles in males may be regarded as closely related conditions since the main pathophysiological cause for both processes is pelvic venous insufficiency. Varicoceles are more prevalent amongst sub-fertile males, with an approximate incidence of 15% in the general male population. PCS is commonly diagnosed amongst premenopausal multiparous women, representing one of the leading causes of chronic pelvic pain. Both conditions appear to be predominantly left-sided and are associated with oxidative stress and pro-inflammatory cascades with subsequent effects on fertility. Clinical examination and pelvic ultrasonography play an essential role in the assessment of varicoceles, PCS and chronic pelvic pain. Venography is generally considered as a gold-standard procedure for both conditions. There is still much debate on how these conditions should be managed. This review article provides a comparative analysis of the underlying pathophysiological mechanisms of both PCS and varicoceles, their impact on fertility, as well as their clinical management.

May-Thurner Syndrome (MTS) remains evasive because of the insidiousness and variable etiologies by which it can manifest. In this study, we examine a unique presentation of MTS resulting from compression of both common iliac veins by a right common iliac artery aneurysm that required complex endovascular venous and arterial intervention.

Whether and when to monitor the amount of anti-factor Xa (aFXa) activity in critically ill patients with complex diseases to prevent venous thromboembolism (VTE) remain unclear. This study is a randomised controlled trial to investigate the effect of aFXa level monitoring on reducing VTE and to establish a new method for accurately preventing VTE in critically ill patients with low-molecular-weight heparin (LMWH).

A randomised controlled trial is planned in two centres with a planned sample size of 858 participants. Participants will be randomly assigned to three groups receiving LMWH prophylaxis at a 1:1:1 ratio: in group A, peak aFXa levels will serve as the guide for the LMWH dose; in group B, the trough aFXa levels will serve as the guide for the LMWH dose; and in group C, participants serving as the control group will receive a fixed dose of LMWH. The peak and trough aFXa levels will be monitored after LMWH (enoxaparin, 40 mg, once daily) reaches a steady state for at least 3 days. The monitoring range for group A's aFXa peak value will be 0.3-0.5 IU/mL, between 0.1 and 0.2 IU/mL is the target range for group B's aFXa trough value. In order to reach the peak or trough aFXa levels, groups A and B will be modified in accordance with the monitoring peak and trough aFXa level. The incidence of VTE will serve as the study's primary outcome indicator. An analysis using the intention-to-treat and per-protocol criterion will serve as the main outcome measurement.

The Xuanwu Hospital Ethics Committee of Capital Medical University and Peking University First Hospital Ethics Committee have approved this investigation. It will be released in all available worldwide, open-access, peer-reviewed publications.

NCT05382481.

May-Thurner syndrome (MTS) can be caused by abdominal aortic aneurysm (AAA) compressing the left common iliac vein against the lumbar vertebra. We reported a rare case of MTS due to AAA Compression successfully treated with anticoagulation.

May-Thurner Syndrome (MTS) is a unique condition characterized by the compression of the left iliac vein by the right common iliac artery, which causes venous outflow obstruction and a high risk of venous sequelae. May-Thurner Syndrome is a condition that is primarily observed in females and is an uncommon cause of deep vein thrombosis (DVT). The more common presentation of DVT is in the lower left extremity, although there have been cases of right-sided formation. In this case report, we present a patient with unprovoked, recurrent, left-sided deep vein thrombosis in a 70-year-old woman. The aim of this case report is to highlight this uncommon condition and to suggest consideration of MTS in the setting of a patient with recurrent unprovoked DVTs of the same extremity.

This study aimed to investigate the association between common iliac vein (CIV) compression and pulmonary embolism (PE) in lower extremity deep vein thrombosis (DVT).

This was a single centre retrospective study. Between January 2016 and December 2021, DVT patients with enhanced computed tomography of the iliac vein and pulmonary artery were included. Patient demographics, comorbidities, risk factors, and degree of CIV compression were collected and analysed. Logistic regression was performed to evaluate the odds ratio (OR) with a 95% confidence interval (CI) of PE in relation to compression severity groups. The association between PE and compression degree was evaluated with restricted cubic splines (RCS) based on an adjusted logistic regression model.

Two hundred and twenty-six DVT patients (left side, n = 153; right side, n = 73) were included. Univariable analyses suggested that symptomatic or asymptomatic PE (54.4%, 123/226) was more common in men (p = .048) and right side DVT (p = .046) patients. Compared with no CIV compression, multivariable analyses suggested that mild compression did not statistically significantly reduce the PE risk, whereas moderate (adjusted OR 0.36; 95% CI 0.15 - 0.88; p = .025) and severe (adjusted OR 0.18; 95% CI 0.06 - 0.54; p = .002) compression statistically significantly reduced the risk. RCS showed that a smaller minimum diameter or greater compression percentage was correlated with continuously decreasing PE risk at a minimum diameter of < 6.77 mm or compression > 42.9%.

PE is more common in men and right side DVT patients. An increasing severity of CIV compression is consistently associated with a decreasing risk of PE when the minimum diameter is < 6.77 mm or the compression is > 42.9%, indicating that it is a protective factor against PE.

Although obesity is a recognized risk factor for the development of lower limb venous disease, less attention has been paid to objectively measuring the effect of centripetal obesity on blood flow in the lower limbs.

The diameter of lower limb veins and venous blood flow were measured in 44 patients (65.6 ± 12.5 years, 25 females, 19 males) with centripetal obesity and chronic venous disease.

The mean diameter of both common femoral veins (CFV) increased significantly in the semi-supine position following elevation of the panniculus (right: ∆0.73 ± 1.21 mm; p ≤ 0.001, left: ∆1.16 ± 1.42 mm; p ≤ 0.001). Moreover, there was a significant increase in venous flow volume in the left CFV (∆62.96 ± 117.85 ml/min; p  =  0.001). Similarly, there was an increase in the diameter of left great saphenous vein (∆0.24 ± 0.41 mm; p  =  0.002), measured at the mid-thigh, when the patient lifted their abdominal panniculus. Finally, the grade of obesity correlated with the extent of the venous disease.

These data provide preliminary evidence that centripetal obesity results in both structural and hemodynamic changes in the lower limb veins, even in the absence of classical reflux.

Common left iliac vein compression, otherwise known as May-Thurner Syndrome (MTS), is a medical condition that refers to chronic compression of an anatomical variant of the left iliac vein by the overlying right common iliac artery and is a predisposing factor for deep vein thrombosis of the left lower limb (LDVT). Although MTS is not often, its true prevalence is underestimated due to misdiagnose, fact that can result to life-threatening conditions such as the development of LDVT and pulmonary embolism. In this paper, we present a case of MTS presenting at our department with unilateral leg swelling without LDTV that was treated through endovascular management along with long-term anticoagulation. With this presentation, the authors wish to emphasise the importance of MTS as a frequently under-diagnosed condition that needs to be ruled out in unilateral left leg swelling with or without LDVT.

Symptomatic compression of the left common iliac vein between the right common iliac artery and spinal vertebrae is referred to as May-Thurner Syndrome (MTS). Atypical cases of MTS including compression of the left external iliac vein, right iliac vein or the inferior vena cava can also coexist and cause double vein compression. Current literature suggests that endovascular treatment including thrombolysis, thrombectomy, venoplasty and stent placement to correct the mechanical obstruction together with anticoagulation therapy is safe and a reasonable management for patients with MTS. Intravascular ultrasound (IVUS) can aid in the diagnosis and the operative planning of MTS, especially regarding sizing and precise deployment of venous stents. Here we present 2 unique atypical cases of MTS with double left iliac vein compression treated endovascularly with stent placement along the common and external iliac vein with the assistance of IVUS.

Interventional radiology has had an expanding role in women's health over the past few decades, with recent accelerated growth and development. Interventional radiology is fundamental in the treatment of multiple conditions that affect women, including pelvic venous disease, uterine fibroids, and adenomyosis, and in postpartum management. Patient workup, classification, and treatment techniques have continued to evolve as interventional radiology has become more prevalent in the treatment of patients affected by these conditions. The authors provide a review of the pathophysiology of, patient workup for, and treatment of pelvic venous disease and uterine artery embolization for various disease processes. The authors also highlight updates from the past 5-10 years in diagnosis, classification, and treatment strategies. ^© RSNA, 2023 Quiz questions for this article are available in the supplemental material.

To evaluate the safety and efficacy of heparin-coated venous stents in animals.

We used atomic layer deposition technology to obtain a heparin coating with good stability and then prepared a heparin-coated venous stent based on this technology. The experimental stents were prepared according to the diameter of the rabbit inferior vena cava and were divided into Ni-Ti alloy stent group, Ni-Ti-Al₂O₃ stent group and Ni-Ti-Al₂O₃-Heparin stent group. 3 days, 7 days and 14 days after stent implantation, the materials were collected, and the three groups of stents were observed by hard tissue section pathology, immunohistochemistry and scanning electron microscope to observe the differences in vascular wall inflammation, thrombosis, lumen stenosis and vascular intima regeneration.

The experiment confirmed the safety of the heparin-coated stent in vivo. Compared with the control group, the experimental group showed a high degree of vascular endothelialization and an intact neointimal structure 14 days after implantation. The long-term safety and biological effects of heparin-coated venous stents in animals require further study.

This study aimed to investigate the association between the left common iliac vein (CIV) compression degree and characteristics of first diagnosed left lower extremity deep vein thrombosis (DVT).

This was a single-center retrospective observational study. Between January 2015 and June 2022, first diagnosed left lower extremity DVT patients with enhanced computed tomography of lower extremities were included. Patient demographics, comorbidities, risk factors, DVT characteristics, and CIV compression degree were collected and analyzed. Logistic regressions were performed to evaluate the odds ratio (OR) with a 95% confidence interval (CI) of iliofemoral or mixed DVT vs. compression percentage. The association between compression percentage and iliofemoral or mixed DVT was evaluated on a continuous scale with restricted cubic splines (RCS). The association between compression percentage and thrombus burden was evaluated using the Spearman test.

A total of 196 (mean age, 61.8 ± 16.1 years; 86 males) patients were included. The median CIV compression percentage in iliofemoral or mixed DVT patients was significantly greater than in non-iliofemoral or non-mixed DVT, respectively (64.4 vs. 46.6%, p < 0.001; 67.8 vs. 54.8%, p = 0.004). CIV compression >50% was associated with significantly increased morbidity of iliofemoral DVT (adjusted OR, 2.96; 95% CI, 1.58-5.52; p = 0.001) or mixed DVT (adjusted OR, 2.39; 95% CI, 1.19-4.81; p = 0.014). RCS showed that a greater compression percentage was associated with a continuously increased OR of iliofemoral DVT (overall p = 0.003, non-linear p = 0.577) or mixed DVT (overall p = 0.020, non-linear p = 0.771). CIV compression percentage had a positive correlation with thrombus burden (rs = 0.284, p < 0.001).

A greater left CIV compression percentage may be associated with increasing likelihood of more proximal location and severe clot extent in first diagnosed left lower extremity DVT.

May-Thurner syndrome (MTS) is an anatomical variant that results in compression of the left common iliac vein by the right common iliac artery. Although often asymptomatic, lower extremity swelling/edema, deep venous thrombosis, post-thrombotic syndrome, and eventual lymphedema (due to long-standing venous obstruction) can develop. The clinical management of patients presenting for lymphedema surgery with concomitant or undiagnosed MTS is not well described.

This review investigates two patients who were evaluated for unilateral lower extremity lymphedema, both of whom were subsequently diagnosed with MTS. Standard imaging (including lymphoscintigraphy, indocyanine green lymphangiography, and magnetic resonance venography) were performed to identify proximal venous obstruction. Treatment was accomplished using vascular surgical management, including stenting of the iliac vein before lymphedema reconstruction with vascularized lymph node transfer and multiple lymphovenous bypass.

Both patients we examined in this review had improvement of lymphedema with vascular surgical management. Literature review reveals that MTS has an incidence as high as 20% in the population, although commonly unidentified due to lack of symptomatology.

There are no studies documenting the incidence of MTS in patients referred for lymphedema surgical management. Routine studies should be obtained to screen for proximal venous obstruction in patients presenting for surgical management of lower extremity lymphedema. Additional research is needed regarding the approach to managing patients with both MTS and lymphedema. Careful observational and prospective studies may elucidate the appropriate time interval between venous stenting and lymphedema microsurgical reconstruction.