Left Common Iliac Vein Research Articles

Intravascular Nodular Fasciitis Mimicking Thrombotic Complications in a 16-year-old male with May-Thurner Syndrome

Abstract Introduction/Objective Nodular fasciitis is a rare benign myofibroblastic proliferation commonly mistaken for malignant tumors due to its rapid growth and clinical presentation. May-Thurner Syndrome (MTS), characterized by compression of the left common iliac vein by the right common iliac artery, predisposes individuals to deep vein thrombosis (DVT). However, here we present a unique case of intravascular nodular fasciitis presenting as thrombotic complications in the context of MTS in a 16-year-old male. Methods/Case Report A 16-year-old male presented with progressive left hip and leg pain accompanied by recent swelling. Ultrasound revealed occlusive thrombi within the left side external iliac, common superficial femoral, and great saphenous veins, along with nonocclusive thrombi in left deep femoral vein. Magnetic resonance venography confirmed MTS and extensive thrombosis. Thrombectomy was done with fragments sent to pathology. Microscopic examination showed cellular areas with loose myxoid composition, proliferating spindle, myofibroblastic/fibroblastic, and stellate cells arranged in irregular bundles. Additional microscopic findings included mild cellular atypia, mitoses, focal macrophage aggregates, occasional multinucleate forms, foci of hemorrhage, fibrin exudate, ingrowing fibroblasts, and increased vascularization. Immunohistochemical stains demonstrated positivity for SMA, CD31, ERG, and CD34, highlighting prominent vascularization, while desmin, myogenin, myoglobin, STAT6, beta-catenin, S100, and AE1/AE3 were negative. Differential diagnosis included intravascular fasciitis, and possibly organizing thrombus with myxoid stroma. USP6 gene rearrangement (FISH) study was positive, confirming the diagnosis of nodular fasciitis. Results (if a Case Study enter NA) N/A Conclusion This case emphasizes the significance of maintaining a broad differential diagnosis when assessing specimens sent as thrombectomies. Recognizing intravascular nodular fasciitis as a potential presentation mimicking thrombosis is essential for accurate diagnosis and management.

Improvement of quality of life in women ≤ 25-years-old with chronic pelvic pain following stenting of nonthrombotic iliac vein compression.

Stenting of nonthrombotic iliac vein compression for chronic pelvic pain (CPP) is controversial, especially in young populations. The current study evaluated the effects of iliac vein stenting on CPP through the assessment of quality-of-life (QoL) and pain scores in female patients ≤25-year-old. A retrospective single site cohort study was conducted for 30 female patients who were treated with left common iliac vein (LCIV) stenting for CPP. QoL was assessed before and after stenting using the following assessments: International Pelvic Pain Society (IPPS), Pelvic Congestion Syndrome (PCS), Pelvic Pain and Urinary Urgency Frequency (PUF), Rome III IBS, ancillary symptoms assessment, and pain scores. Secondary evaluation of the accuracy of radiologic interpretations of iliac vein compression on CT and MRI was also performed. Finally, commonly associated comorbidities within this population were assessed. Patient reported outcomes in 30 iliac vein stent patients demonstrated improvements in QoL post-stenting as demonstrated through significant reductions in IPPS, PCS, and pain scores (p = .0103, .0156, and .0092, respectively). Many of the cross-sectional imaging studies that were read by the interpreting radiologist as normal or mild compression were later identified as moderate or severe by the interventional radiologist clinically evaluating the patient. These patients went on to show significant compression on venography and intravascular ultrasound with associated clinical improvement after stenting. Significant improvements in QoL were identified in young women with CPP after LCIV stenting. Similarities in the clinical presentation of common comorbidities and misinterpretation of cross-sectional imaging studies may make the identification of pelvic venous disease more challenging. Our findings endorse the need for further research on stenting in young women with venous origin CPP through comparative outcomes studies and blinded randomized controlled trials.

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

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). To analyze the correlation between iliac vessel geometry and probability of DVT in patients with MTS. 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. 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). 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.

Left-Sided Inferior Vena Cava: A Retrospective Study and Literature Review

ObjectiveThe primary goal of this research is to delve into the clinical and pathological facets of the left-sided inferior vena cava (IVC), and to catalogue and condense its radiological and clinical attributes, thereby furnishing valuable references for pertinent clinical diagnosis and therapeutic procedures. MethodsWe collated and scrutinized the general clinical features, radiological characteristics, and diagnostic and therapeutic strategies of 30 patients diagnosed with left-sided IVC in our hospital from July 2014 through February 2024. ResultsA majority of patients were asymptomatic and were only identified during diagnostic procedures for other ailments. CT scans revealed anomalies in the anatomical configuration of the left-sided IVC. The radiological presentations primarily showcased the right common iliac vein traversing the lumbar vertebrae to amalgamate with the left common iliac vein, forming the IVC. The IVC ascended on the left side of the abdominal aorta, accepted the left renal vein, and then transitioned to the right side of the abdominal aorta. In three instances, the IVC was witnessed ascending on the left side of the abdominal aorta, permeating through the diaphragm, converging with the azygos vein and abdominal aorta, and making its way into the right atrium. In these cases, the hepatic segment of the IVC was missing, and there was an absence of the IVC inferior to the hepatic vein, a condition we refer to as complete left-sided IVC. ConclusionLeft-sided IVC is predominantly asymptomatic but carries significant anatomical implications during abdominal, retroperitoneal surgeries, and vascular interventions. Precise identification and management of this anomaly can mitigate surgical risks and enhance patient prognosis.

Leiomyosarcoma of vascular origin: lessons learned from misdiagnosis

BackgroundLeiomyosarcoma (LMS) of vascular origin is a rare entity of soft tissue sarcomas. Although they arise mostly from retroperitoneal major vascular structures, some encountered cases may arise from the smaller vascular structures of the thigh as the femoral vein. Due to their origin from the vascular structures, they represent a diagnostic challenge as they may be misdiagnosed as deep vein thrombosis (DVT).Case presentationWe present a case of a 45-year-old woman with left femoral and iliac vein LMS that was previously described in the vascular ultrasound (US) report as extensive DVT involving the femoral and external iliac veins. The patient did not improve after receiving the prescribed anticoagulants. Seven months later, the patient underwent computerized tomography (CT) with contrast, revealing a soft tissue mass in the anatomical site of the left common femoral and external iliac veins. The patient underwent both US-guided tru-cut biopsy and incisional biopsy from the iliac lymph nodes which revealed leiomyosarcoma.Materials and methodsThe patient underwent both vascular ultrasound and magnetic resonance imaging of the pelvis and the left thigh at the time of the first presentation. Seven months later, she underwent contrast-enhanced CT of the abdomen and pelvis.OutcomeThe patient was referred to the oncology department to receive the appropriate chemotherapy protocol as the tumor was inoperable.ConclusionsAlthough leiomyosarcoma of vascular origin is a rare entity of neoplasms, it is usually underestimated. A high index of suspicion would help the clinician to suspect such a neoplasm and save time for early diagnosis and management. Special caution should be taken for patients with venous thrombosis not improving on anticoagulants. When there is suspicion, other modalities such as computerized tomography and magnetic resonance imaging help confirm the diagnosis.

Prospective Cohort Study of a Treatment Strategy for a Combination of the Left Common Iliac Vein Compression Stenosis and Pelvic Venous Insufficiency.

To develop a strategy for the iliac vein stenting in patients with a combination of the left common iliac vein (LCIV) compression stenosis and pelvic venous insufficiency (PVI). This prospective comparative cohort study included 55 patients with hemodynamically significant LCIV stenosis out of 285 females with PVI screened in 2014-2022. All 55 patients underwent duplex ultrasound, multi-detector computed venography, ovarian venography, and multiplanar pelvic venography. Patients underwent LCIV stenting or the left gonadal vein (LGV) embolization as the primary intervention. The endpoints (chronic pelvic pain [CPP] relief, patency of stents, and reduction in pelvic venous reflux [PVR]) were evaluated 1 and 10 days, as well as 1, 6, and 12 months after the procedure. All patients received antithrombotic therapy after the interventions. The primary LCIV stenting was performed in 49 patients and resulted in the CPP relief in 69.4%, pain reduction from 7.9±1.3 to 1.7±1.1 visual analog scale (VAS) scores (p=0.005), and substantial reduction of PVR in LGV (from 4.3±0.6 seconds to 1.9±0.3 seconds, p=0.003). The LGV embolization as the second stage of treatment was performed in 30.6% of patients with the LGV reflux greater than 5 seconds as a possible cause for the CPP persistence. The primary LGV embolization failed in 100% of patients (no changes in CPP and PVR). The LCIV stenting at the second stage resulted in the CPP relief within 10 days and the pelvic venous reflux (PVR) reduction. There were no complications of stenting, and the patency of stents in the follow-up period was 100%. Postembolization syndrome occurred in 9.5% of patients. No thromboses of the veins of the pelvis and lower extremities were identified. Treatment of patients with a combination of LCIV compression and PVI involves staged endovascular interventions: the LCIV stenting should be considered the first-line treatment, while the LGV embolization is performed when the PVI symptoms persist for more than 6 months and is not acceptable as the first-line treatment. The developed strategy of endovascular treatment for the combination of left common iliac vein (LCIV) and pelvic venous insufficiency (PVI) provides an effective elimination of chronic pelvic pain (CPP) and reflux in the pelvic veins and avoids unnecessary embolizations of the gonadal veins, thereby eliminating possible risks related to complications of embolization. The use of antithrombotic therapy is an effective and safe approach for preventing venous thromboembolic events after endovascular interventions.

Haemodynamic study of left nonthrombotic iliac vein lesions: a preliminary report

Nonthrombotic iliac vein lesions (NIVLs) are significant causes of chronic venous insufficiency (CVI) in the left lower limb and symptom recurrence following left lower limb varicose vein treatment. The goal of this study was to explore the haemodynamic and morphological characteristics of iliac veins in patients with NIVLs. Pressure at the caudal end of the stenotic left common iliac vein (LCIV) segment, local blood flow velocity, and time-averaged wall shear stress in the stenotic segment exhibited positive correlations with the clinical CVI classification (R = 0.92, p < 0.001; R = 0.94, p < 0.001; R = 0.87, p < 0.001), while the relative retention time showed a negative correlation (R = -0.94, p < 0.001). The pressure difference (∆P) between the two ends of the stenotic segment and the velocity difference (∆V) between the stenotic segment and the caudal end were positively correlated with the clinical classification (R = 0.92, p < 0.001; R = 0.9, p < 0.001). The cross-sectional area stenosis rate and length of the stenotic LCIV segment were positively correlated with the clinical classification (R = 0.93, p < 0.001; R = 0.63, p < 0.001). The results suggest that haemodynamic assessment of the iliac vein could effectively portray blood flow disturbances in stenotic segments of the LCIV, potentially reflecting the degree of iliac vein stenosis. Haemodynamic indicators are correlated with the severity of clinical CVI symptoms.

Percutaneous Transluminal Angioplasty Alleviate Pediatric Postthrombotic Syndrome: A Case Report and Literature Review.

Postthrombotic syndrome (PTS) is one of the long-term sequelae of deep vein thrombosis (DVT), and effective symptom management in pediatric PTS remains a challenge, with interventional therapy rarely explored in this population. We present a successful case of interventional treatment pediatric PTS, resulting in a remarkable amelioration of her symptoms. This case features a 6-year-old girl diagnosed with hyperinsulinemia, leading to a hypoglycemic coma. Following a mini-pancreatic partial pancreatectomy, she required further intensive care in the pediatric intensive care unit. It was during this period that left lower extremity DVT was identified, prompting warfarin anticoagulation therapy. During the anticoagulation period, she had several bleeding events and was switched to anticoagulation with low molecular heparin. One month later, the left common iliac vein and external iliac vein was found to be completely occluded. Over time, she experienced a gradual onset of lower limb swelling and pain, which, after 6 months, was accompanied by perineal edema and venous claudication. As a result, she underwent successful percutaneous transluminal angioplasty. In addition, the anticoagulation regimen was adjusted to rivaroxaban. At the 8-month follow-up, we observed significantly improvement in her postoperative lower extremity swelling and symptoms related to venous occlusion had completely disappeared. Moreover, vascular imaging confirmed improvement in stenosis and uninterrupted blood flow. In our review of pediatric PTS studies, we observed limited options to alleviate symptoms, and interventional treatments have not been reported. Our case study, demonstrating the safe and effective use of percutaneous transluminal angioplasty, helps to illuminate this area and alleviate pediatric PTS symptoms. This case validates the efficacy and safety of using percutaneous transluminal angioplasty (PTA) for the treatment of postthrombotic syndrome (PTS) in pediatric patients. This interventional approach offers significant symptomatic relief and improves quality of life, especially in cases where traditional anticoagulation therapies fail or lead to complications. The successful case presented emphasizes the necessity of considering endovascular interventions for children with moderate to severe PTS, particularly when conservative management is ineffective. This research underscores the potential for PTA to be adopted in clinical practice, offering a promising new approach for managing pediatric PTS.

Extensive Left Sided Venous Thrombi and Bilateral Pulmonary Emboli in the Context of May-Thurner Syndrome for a Patient Presenting with Acute Flank Pain: A Case Report

May-Thurner syndrome is an underappreciated differential in the context of deep venous thrombosis. It is a symptomatic congenital abnormality resulting from compression of the left common iliac vein, sometimes also referred to as iliac vein compression syndrome in the literature. This case reports the presentation of a female with acute flank pain to the emergency department following a recent laparotomy for a complicated tubo-ovarian abscess. She was subsequently diagnosed with a sub-acute thrombus extending from the left common femoral vein into the left inferior vena cava, as well as new bilateral pulmonary emboli. As the patient had relative contraindications to thrombolysis, a shared decision was made with the vascular team to opt for conservative management only. In this instance, this included long-term oral anticoagulant therapy and compression stockings. This case asserts that clinicians should maintain a high index of suspicion for May-Thurner syndrome in the context of extensive left-sided thrombus formation.

Current Diagnostic and Therapeutic Approaches in May-Thurner Syndrome in Children, Adolescents, and Young Adults: A Survey among Thrombosis Experts of the German Society of Thrombosis and Haemostasis.

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.

Total Endovascular Repair of a Giant Iliac Vein Aneurysm: A Case Report and Review of Literature.

The iliac veins are the least frequent location for venous aneurysms, with only a few cases described globally. The etiology and clinical presentation of this extremely rare entity is diverse and unclear and no treatment consensus has been reached yet. Our purpose is to present an interesting iliac vein aneurysm (IVA) case that we treated in our department, with a brief review of the literature. We report a case of a 74-year-old male patient with a giant, 55 mm in diameter, asymptomatic, right common IVA, with concurrent aplasia of the left common iliac vein and an extensive network of venous collaterals. The patient was treated, under general anesthesia, with total endovascular iliocaval reconstruction through implantation of a 32 × 100 mm thoracic aortic tubular Ankura stent graft. The computed tomography venography at first-month follow-up showed the complete exclusion of the IVA, without any endoleak and the patient remains up to date free of symptoms and thromboembolic events. Twelve cases of endovascular treatment of IVA have been reported so far, and our case is the first with implantation of a thoracic aortic stent graft. Our results suggest that this technique is safe, effective, and may be considered for appropriately selected patients. This is the first case with total endovascular repair of an iliac vein aneurysm with contralateral iliac vein aplasia through endovenous implantation of a thoracic aortic stent-graft. Our results suggest that this technique is safe and effective and thus, may be considered for appropriately selected cases.

A novel surgical approach using the "lateral corridor" for minimally invasive oblique lumbar interbody fusion at L5-S1: a clinical series and technical note.

The minimally invasive oblique lumbar interbody fusion (MI-OLIF) L5-S1 was introduced to overcome the limitations of conventional fusion techniques, however, MI-OLIF is not possible using the standard method due to vascular structures in some cases. We aimed to introduce the "lateral corridor" and report the details of the surgical technique with a clinical case series. We utilized the lateral access route of the left common iliac vein and named it the "lateral corridor", to distinguish the technique from the standard technique (central corridor). The type and frequency of branch vessels that required additional manipulations were reviewed, and the frequency of intraoperative vascular injury was investigated. Among the 107 patients who underwent MI-OLIF L5-S1, 26 patients (24.3%) who received the "lateral corridor" technique were included. Branch vessel ligation was required in 42.3% of the patients. The types of branch vessels that required ligation were seven cases (26.9%) of the iliolumbar vein (ILV) and six cases (23.1%) of ascending lumbar vein (ALV). The ILV and ALV were ligated in two cases. None of the patients developed intraoperative vascular injuries. We introduced the "lateral corridor" as an alternative approach for MI-OLIF L5-S1, implemented it in 24.3% of the patient cohort, and reported favorable outcomes devoid of vascular complications. The "lateral corridor" necessitated ligation of the ILV or ALV in 42.3% of cases. The "lateral corridor" approach appears to be a promising surgical technique, offering feasibility even in instances where the vascular anatomy precludes the employment of the conventional approach.

Abstract 3088: Inferior Vena Cava (IVC) Thrombosis In A Patient With May Thurner Syndrome: A Rare Case Of Thrombotic Iliocaval Obstruction In Octogenarian Population.

Introduction: May Thurner Syndrome is an extrinsic compression of the left common iliac vein by the right common iliac artery against lumbar spine. It is a rare cause of the lower extremity deep venous thrombosis (DVT) in octogenarian population. There is barely any data to document the association of IVC thrombosis with May Thurner Syndrome. Blood stasis in the setting of venous compression can increase the risk for DVT distally but proximal DVT is rare in absence of any other risk factors of thromboembolism. Case Representation: We present a unique case of 86-year-old female who was incidentally diagnosed with IVC thrombosis, left common iliac vein thrombosis, and left sided May Thurner Syndrome that is never documented before in octogenarian population. She had IVC thrombosis extending to the left common iliac vein with extrinsic compression by the right common iliac artery. This case is unique as our patient did not have any risk factor for venous thrombosis other than May Thurner Syndrome. Conclusion: May Thurner Syndrome can increase the risk for DVT proximal propagation and IVC thrombosis. The management of IVC thrombosis and May Thurner Syndrome in octogenarian population needs to account for risk of pulmonary embolism and mortality when avoiding anticoagulation compared to risk of morbidity and mortality from bleeding with anticoagulation. The decision to further manage depends upon clinical features, risk factors and institutional resources.

Heat therapy preconditioning improves the skeletal muscle contractile and mitochondrial function in a mouse model of access-related hand dysfunction

Introduction: Hemodialysis via arteriovenous fistula (AVF) is a life-line treatment for patients with end-stage kidney disease. However, hemodialysis access-related hand dysfunction (ARHD) including ischemia, muscle weakness and alterations in mitochondrial function is prevalent following AVF placement. We tested the hypothesis that two-weeks of daily heat therapy prior to AVF surgery would improve hindlimb function in a mouse model of ARHD. Methods: Adult male C57BL/6J mice (N=9-11/group) were fed a 0.2% adenine diet to induce chronic kidney disease. Following two weeks of the initial adenine diet, animals were randomly allocated to heat therapy (HT) or control (CON) groups. Animals assigned to HT were exposed to environmental heat at 40°C in a climate chamber for 30 min/day, six days/week, for two weeks while the control mice were exposed to room temperature (~22°C). The AVF was created using the left common iliac artery and vein 24-48 hours after the last treatment session. Laser Doppler perfusion to the ventral paw was assessed post-operatively (POD) and AVF patency was verified using a high-frequency duplex ultrasound system three days prior to euthanasia. Following 14 days of recovery, in situ tibialis anterior (TA) muscle contractility and gastrocnemius muscle mitochondrial function were assessed. RNA sequencing analysis of the hindlimb skeletal muscle (N=4/group) was performed. Results: Compared to baseline, the level of blood urea nitrogen was similarly elevated ( P&lt;0.05) in both groups following four weeks of adenine diet. In both groups, blood perfusion to the paw was decreased by ~50% immediately after AVF creation and progressively recovered to ~80% at POD13 without a treatment effect ( P=0.4467). No differences in body weight and muscle mass in the TA, extensor digitorum longus, and soleus muscles were observed (all P&gt;0.05). Notably, however, the absolute ( P=0.0250) and specific force ( P=0.0101) frequency relationship of the TA muscle were significantly improved in the animals exposed to HT. In addition, compared with control animals, HT mice had significant improvement in oxidative phosphorylation (OXPHOS) in both pyruvate ( P=0.0145) and octanoylcarnitine ( P=0.0196) fueled conditions. RNA sequencing results revealed that genes involved in nervous system development and metabolism were significantly different between HT and CON groups. Conclusion: Daily application of heat therapy for two weeks prior to the AVF surgery has beneficial effects on both skeletal muscle contractile and mitochondrial function suggesting this pre-habilitation strategy may mitigate the risk of ARHD in patients undergoing AVF surgery. Funding Support: National Institutes of Health grant R01HL148597 and American Heart Association grant POST903198. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

In vivo evaluation of safety and performance of a tapered nitinol venous stent with inclined proximal end in an ovine iliac venous model

A tapered stent with inclined proximal end is designed for fitting the iliac anatomically. The aim of the present study was to evaluate the safety and performance of the new stent in ovine left iliac veins. The experiment was performed in 30 adult sheep, and one nitinol-based VENA-BT® iliac venous stent (KYD stent) was implanted into each animal’s left common iliac vein. Follow-up in all sheep consisted of angiographic, macroscopic, and microscopic examinations at Day 0 (< 24 h), Day 30, Day 90, Day 180 and Day 360 post-stenting (six animals per each time-point). 30 healthy ~ 50 kg sheep were included in this study and randomly divided into five groups according to the follow-up timepoint. All stents were implanted successfully into the left ovine common iliac vein. No significant migration occurred at follow-up. There is no statistically significant difference between the groups (p > 0.05), indicating no serious lumen loss occurred during the follow-up period. Common iliac venous pressure was further measured and the results further indicated the lumen patency at follow-up. Histological examinations indicated that no vessel injury and wall rupture, stent damage, and luminal thrombus occurred. There was moderate inflammatory cell infiltration around the stent in Day-0 and Day-30 groups with the average inflammation score of 2.278 and 2.167, respectively. The inflammatory reaction was significantly reduced in Day-90, Day-180 and Day-360 groups and the average inflammation scores were 0.9444 (p < 0.001, Day-90 vs Day-0), 1.167 (p < 0.001, Day-180 vs Day-0) and 0.667 (p < 0.001, Day-90 vs Day-0), respectively. The microscopic examinations found that the stents were well covered by endothelial cells in all follow-up time points. The results suggested that the KYD stent is feasible and safe in animal model. Future clinical studies may be required to further evaluate its safety and efficacy.

Clinical Significance of Degree of Iliocaval Obstruction Based on Intravascular Ultrasound Use

Abstract Objective: Endovenous therapy serves as the preferred treatment for patients with May–Thurner syndrome (MTS) who have significant symptoms. While stenting for MTS generally yields better results than for postthrombotic syndrome, it remains unclear whether the severity of stenosis specifically in MTS influences these outcomes. This study aims at assessing the effect of the degree of stenosis on endovascular therapy for MTS. Methods: The retrospective study included 73 patients who presented for deep venous stenting of the lower limb at a tertiary center between 2018 and 2022. Based on the intravascular ultrasound (IVUS) use, patients were divided into two groups according to degree of stenosis: 50%–80% and &gt;80% stenosis. Both groups were compared regarding demographics, clinical presentations, procedural details, and postoperative outcomes. Results: Significant &gt;80% stenosis was detected in 45.2% of cases. There was no significant difference regarding demographics and comorbidities except for body mass index (BMI) as patients with &gt;80% stenosis were more likely to have higher BMI (P = 0.05). Patients with &gt;80% stenosis were more likely to have a prior history of DVT (21.2% vs. 5%; P = 0.036). There was no statistical difference in the clinical picture of both groups except for higher rates of active venous ulcer in patients with &gt;80% stenosis (21% vs. 5%: P =0.001). Patients with 50%–80% stenosis were more likely to present with atypical varicosities (50% vs. 21%; P = 0.011). Patients with &gt;80% stenosis were more likely to have venographic features of stenosis as pelvic collateral and ascending lumbar veins (P = 0.0007 and P &lt; 0.0001, respectively). After a mean clinical follow-up of 414.6 ± 587.5, primary patency was higher for the 50%–80% stenosis, 90.9% versus 74.4% (Log-rank test = 0.012). Conclusion: The severity of iliac vein stenosis/compression is associated with more advanced clinical presentations and more venographic signs of collateralizations. IVUS serves as a more sensitive tool than computed tomography venography in detecting left common iliac vein critical stenosis. More than 80% can serve as a proper cutoff point for critical venous stenosis that warrants more aggressive therapy and closer follow-up. A critical degree of stenosis was associated with lower patency rates when compared to 50%–80% stenosis.

Risk factors for vascular injuries in anterior lumbar interbody fusion: a single-institution retrospective study.

Vascular injuries in anterior lumbar interbody fusion (ALIF) occur due to the vascular manipulation needed to achieve optimal disc space exposure. In this study, the authors aimed to evaluate intraoperative vascular injuries in patients undergoing single- and multilevel ALIF at a large tertiary academic center. Prospectively collected data specifically addressing postoperative complications in patients who underwent ALIF by neurosurgery spine faculty working with a specialized vascular surgeon were retrospectively reviewed. Demographic characteristics and intraoperative data were collected. Patients were split into vascular injury and non-vascular injury groups. Outcome comparisons were conducted using the chi-square exact and Wilcoxon rank-sum tests for categorical and continuous data, respectively. Logistic regression was used to investigate associations with vascular injury, with univariate analysis first conducted to identify candidate associations. Based on these results, variables demonstrating a between-groups test statistic of p < 0.10 were included in the multivariate analysis to determine the independent predictors of vascular injuries. In total, 323 patients who underwent ALIF procedures were identified: 51% were male (n = 166) and 49% were female (n = 157). The mean age was 57.1 years, with 56% (n = 182) having undergone prior lumbar surgery. Vascular injuries were encountered intraoperatively in 7.1% (n = 23) of patients, and the majority (91% [n = 21]) involved the left common iliac vein. Patients with vascular injuries were statistically older (mean 63.6 vs 56.6 years), had greater incidence rates of coronary artery disease, opioid use, multilevel ALIF surgery involving the L2-3 level, and surgery involving multiple disc spaces, had more multilevel anterior instrumentation, and experienced greater blood loss during surgery and longer length of stay (all p < 0.05). Overall, there was 1 death (0.3%) secondary to aortic artery injury. Multivariate analysis identified opioid use, multilevel ALIF involving L2-3, and multiple interbodies as statistically independent predictors of vascular injury (all p < 0.05). Identifying patient risk factors can reduce the risk of vascular injuries in ALIF. Opioid use, multilevel ALIF involving L2-3, and multiple interbodies were independent predictors of vascular injuries in ALIF.

Atypical May-Thurner Syndrome Caused by Large Lumbar Osteophyte

AbstractAn 82-year-old man presented to the emergency department with intermittent left lower extremity swelling for the last 4 to 5 months that limited his daily activities. The patient had a negative lower extremity venous duplex 3 months prior and had been treating symptoms with compression stockings but experienced no improvement. Venography showed venous outflow obstruction in his left common iliac vein and the etiology was confirmed to be a lumbar vertebral osteophyte compressing the vein. The patient underwent endovascular treatment with balloon venoplasty and stent placement over the lesion with return of adequate outflow. This report describes treatment of symptomatic left common iliac venous compression with endovascular therapy alone.

A cadaver study evaluating intraluminal anomalies of the left common iliac vein

ObjectiveIntraluminal 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. MethodsDissection 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. ResultsSpurs 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). ConclusionsStudy 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.

A comparative study of altered hemodynamics in iliac vein compression syndrome.

Introduction: Iliac vein compression syndrome (IVCS) is present in over 20% of the population and is associated with left leg pain, swelling, and thrombosis. IVCS symptoms are thought to be induced by altered pelvic hemodynamics, however, there currently exists a knowledge gap on the hemodynamic differences between IVCS and healthy patients. To elucidate those differences, we carried out a patient-specific, computational modeling comparative study. Methods: Computed tomography and ultrasound velocity and area data were used to build and validate computational models for a cohort of IVCS (N = 4, Subject group) and control (N = 4, Control group) patients. Flow, cross-sectional area, and shear rate were compared between the right common iliac vein (RCIV) and left common iliac vein (LCIV) for each group and between the Subject and Control groups for the same vessel. Results: For the IVCS patients, LCIV mean shear rate was higher than RCIV mean shear rate (550 ± 103s-1 vs. 113 ± 48s-1, p = 0.0009). Furthermore, LCIV mean shear rate was higher in the Subject group than in the Control group (550 ± 103s-1 vs. 75 ± 37s-1, p = 0.0001). Lastly, the LCIV/RCIV shear rate ratio was 4.6 times greater in the Subject group than in the Control group (6.56 ± 0.9 vs. 1.43 ± 0.6, p = 0.00008). Discussion: Our analyses revealed that IVCS patients have elevated shear rates which may explain a higher thrombosis risk and suggest that their thrombus initiation process may share aspects of arterial thrombosis. We have identified hemodynamic metrics that revealed profound differences between IVCS patients and Controls, and between RCIV and LCIV in the IVCS patients. Based on these metrics, we propose that non-invasive measurement of shear rate may aid with stratification of patients with moderate compression in which treatment is highly variable. More investigation is needed to assess the prognostic value of shear rate and shear rate ratio as clinical metrics and to understand the mechanisms of thrombus formation in IVCS patients.