Venous Interventions: Controversies in the Management of Acute Deep Venous Thrombosis and the Role of the Interventional Radiologist.

Lower extremity deep venous thrombosis (DVT) is estimated to occur in 1 in 1000 persons annually in adult populations, with prevalence predicted to double by the year 2050. While acute DVT and pulmonary embolism are a major cause of cardiovascular morbidity and mortality, the long-term prognosis for patients with venous thromboembolism is in part determined by the development of post-thrombotic syndrome (PTS), which occurs in up to 50% of patients. PTS refers to a chronic syndrome complex, invariably characterized by intractable edema, pain, stasis dermatitis, and venous stasis ulceration when severe.

Intravascular Ultrasound Use in Peripheral Arterial and Deep Venous Interventions: Multidisciplinary Expert Opinion From SCAI/AVF/AVLS/SIR/SVM/SVS.

Percutaneous revascularization is the primary strategy for treating lower extremity venous and arterial disease. Angiography is limited by its ability to accurately size vessels, precisely determine the degree of stenosis and length of lesions, characterize lesion morphology, or correctly diagnose postintervention complications. These limitations are overcome with use of intravascular ultrasound (IVUS). IVUS has demonstrated the ability to improve outcomes following percutaneous coronary intervention, and there is increasing evidence to support its benefits in the setting of peripheral vascular intervention. At this stage in its evolution, there remains a need to standardize the use and approach to peripheral vascular IVUS imaging. This manuscript represents considerations and consensus perspectives that emerged from a roundtable discussion including 15 physicians with expertise in interventional cardiology, interventional radiology, and vascular surgery, representing 6 cardiovascular specialty societies, held on February 3, 2023. The roundtable's aims were to assess the current state of lower extremity revascularization, identify knowledge gaps and need for evidence, and determine how IVUS can improve care and outcomes for patients with peripheral arterial and deep venous pathology.

Modern Treatment of Pulmonary Embolism (USCDT vs MT): Results From a Real-World, Big Data Analysis (REAL-PE).

Background: Advanced therapies are increasingly utilized to treat pulmonary embolism (PE). A unique data platform allows access to electronic health record data for comparison of the safety of PE therapies. Methods: All data from Truveta (Truveta, Inc) were analyzed (16 systems, 83,612,413 patients, 535,567 with PE). All patients treated with ultrasound-assisted catheter-directed thrombolysis (USCDT) (Boston Scientific) or mechanical thrombectomy (MT) (Inari Medical) for PE were identified. The primary analysis was based on index procedures performed from January 2009 to May 2023, and contemporary analysis on those performed from January 2018 to May 2023. Bleeding was assessed via direct laboratory analysis and transfusion administration documentation. International Society for Thrombosis and Hemostasis (ISTH) and Bleeding Academic Research Consortium (BARC) 3b definitions were recreated. Multiple logistic regression analysis of major bleeding was performed. In-hospital death and median length of stay were measured. Results: For the primary analysis, 2259 patients (N = 1577 USCDT, N = 682 MT) and for the contemporary analysis 1798 patients (N = 1137 USCDT, N = 661 MT) met the criteria. Incidence of hemoglobin reduction (>2 and >5 g/dL) and transfusions received were significantly higher among MT-treated patients in both analyses, as was ISTH and BARC 3b major bleeding (primary: ISTH MT 17.3% vs USCDT 12.4% P = .002; BARC 3b MT 15.4% vs USCDT 11.8% P = .019) (contemporary: ISTH MT 17.2% vs USCDT 11.0% P = .0002; BARC 3b MT 15.4% vs USCDT 10.6% P = .002). Regression analysis demonstrated that MT is associated with major bleeding. Median length of stay, all-cause 30-day readmission and in-hospital mortality were similar between groups. Intracranial hemorrhage was more common with MT. Conclusions: Major bleeding derived from direct laboratory and transfusion data occurred more frequently with MT vs USCDT. Intracranial hemorrhage was more common among MT-treated patients. In the absence of randomized data, these results provide guidance regarding the bleeding risk and safety of strategies for advanced PE therapy.

Consensus Statement on the Management of Nonthrombotic Iliac Vein Lesions From the VIVA Foundation, the American Venous Forum, and the American Vein and Lymphatic Society.

A nonthrombotic iliac vein lesion is defined as the extrinsic compression of the iliac vein. Symptoms of lower extremity chronic venous insufficiency or pelvic venous disease can develop secondary to nonthrombotic iliac vein lesion. Anatomic compression has been observed in both symptomatic and asymptomatic patients. Causative factors that lead to symptomatic manifestations remain unclear. To provide guidance for providers treating patients with nonthrombotic iliac vein lesion, the VIVA Foundation convened a multidisciplinary group of leaders in venous disease management with representatives from the American Venous Forum and the American Vein and Lymphatic Society. Consensus statements regarding nonthrombotic iliac vein lesions were drafted by the participants to address patient selection, imaging for diagnosis, technical considerations for stent placement, postprocedure management, and future research/educational needs.

Fatigue Test Method to Evaluate the 50 Year Durability of Venous Stents.

OBJECTIVE: Iliofemoral venous obstructive disease can result in significant, potentially debilitating symptoms that can negatively affect quality of life. Unlike arterial disease, patients with deep venous disease have a significantly lower median age, therefore the need for long term stent patency becomes a matter of decades rather than years. Furthermore, iliofemoral lesions frequently require stent placement across the inguinal ligament. Such stents are subject to dynamic stress from leg movement and associated concerns for device fatigue, resulting in stent fracture. The aim of this study was to describe an in vitro 50 year stent fatigue test method designed to assess durability against dynamic stress induced device fracture. METHODS: Through literature review, cadaver studies, and computer modelling, the most challenging loading was confirmed to be hip flexion across the inguinal ligament. This occurs when the patient adjusts between a seated and standing position. Sit to stand hip flexion at the inguinal ligament was effectively simulated on the bench in this in vitro experimental study. RESULTS: When tested under challenge parameters, hip flexion was reliably found to cause fractures in non-venous nitinol stents. However, a dedicated self expanding nitinol venous stent, engineered for improved durability, underwent up to 50 years of simulated loading on the bench with 15% (3/20) of stents experiencing fractures at 50 years, compared with fractures in 35% (14/40) of non-venous stents tested to 1.4 years; no statistical testing was performed as durations do not match and the objective was to demonstrate the test method. CONCLUSION: The presented fatigue test method is a suitable approach for evaluating the durability of stents intended for venous use. Venous stents demonstrated superior fatigue resistance compared with non-venous stents via in vitro hip flexion testing.

Inferior Vena Cava Filter Retrieval: Simple to Complex.

Retrievable inferior vena cava filters were designed to provide mechanical prophylaxis from pulmonary embolism with the intent for retrieval once no longer indicated, and have been utilized at a high rate since their introduction. Unfortunately, retrieval rates have historically lagged behind, in part due to significant rates of failed standard retrieval techniques for filters with prolonged dwell time. Refinement in advanced retrieval techniques has now allowed (in experienced centers) for safe removal of filters previously considered irretrievable. An individualized approach is necessary for each potential advanced filter retrieval to determine appropriate course of action. This review will emphasize complex filter retrieval techniques amidst a larger discussion of inferior vena cava filters and their management.

Intravascular Ultrasound Use in Peripheral Arterial and Deep Venous Interventions: Multidisciplinary Expert Opinion From SCAI/AVF/AVLS/SIR/SVM/SVS.

Percutaneous revascularization is the primary strategy for treating lower extremity venous and arterial disease. Angiography is limited by its ability to accurately size vessels, precisely determine the degree of stenosis and length of lesions, characterize lesion morphology, or correctly diagnose postintervention complications. These limitations are overcome with use of intravascular ultrasound (IVUS). IVUS has demonstrated the ability to improve outcomes following percutaneous coronary intervention, and there is increasing evidence to support its benefits in the setting of peripheral vascular intervention. At this stage in its evolution, there remains a need to standardize the use and approach to peripheral vascular IVUS imaging. This manuscript represents considerations and consensus perspectives that emerged from a roundtable discussion including 15 physicians with expertise in interventional cardiology, interventional radiology, and vascular surgery, representing 6 cardiovascular specialty societies, held on February 3, 2023. The roundtable's aims were to assess the current state of lower extremity revascularization, identify knowledge gaps and need for evidence, and determine how IVUS can improve care and outcomes for patients with peripheral arterial and deep venous pathology.

The role of iliac vein stent placement in pelvic venous disorder management.

Pelvic venous disease (PeVD) has historically been challenging to diagnose and treat. This paper describes a comprehensive approach to the diagnosis of PeVD and reviews the role of iliac vein stent placement in treatment. Patient selection is vital for non-thrombotic iliac vein lesions (NIVLs) as only a small subset of patients with an NIVL will benefit from stent placement. There is limited, inconclusive data on optimal treatment for patients with both primary ovarian vein reflux and an NIVL. Patients with chronic post-thrombotic outflow obstruction typically have a more favorable risk/benefit ratio for intervention but require anticoagulation and close follow-up due to poorer long-term stent patency. Intravascular ultrasound is a useful tool for identifying obstructive lesions, sizing stents, and planning landing zones. More research is needed to characterize underlying pathophysiology, validate thresholds for intervention, develop reliable methods for outcomes assessment, and determine treatment response. Until this data is produced, an individualized treatment approach is warranted.

Research Consensus Panel Follow-up: 8-Year Update on Submassive Pulmonary Embolism.

The 2015 Research Consensus Panel (RCP) on submassive pulmonary embolism (PE) set priorities for research in submassive PE and identified a rigorous randomized trial of catheter-directed therapy plus anticoagulation versus anticoagulation alone as the highest research priority. This update, written 8 years after the RCP was convened, describes the current state of endovascular PE practice and the Pulmonary Embolism-Thrombus Removal with Catheter-Directed Therapy trial, the main output from the RCP.

Society of Interventional Radiology Position Statement on the Management of Chronic Iliofemoral Venous Obstruction with Endovascular Placement of Metallic Stents.

PURPOSE: To state the position of the Society of Interventional Radiology (SIR) on the endovascular management of chronic iliofemoral venous obstruction with metallic stents. MATERIALS AND METHODS: A multidisciplinary writing group with expertise in treating venous disease was convened by SIR. A comprehensive literature search was conducted to identify studies on the topic of interest. Recommendations were drafted and graded according to the updated SIR evidence grading system. A modified Delphi technique was used to achieve consensus agreement on the recommendation statements. RESULTS: A total of 41 studies, including randomized trials, systematic reviews and meta-analyses, prospective single-arm studies, and retrospective studies were identified. The expert writing group developed 15 recommendations on the use of endovascular stent placement. CONCLUSIONS: SIR considers the use of endovascular stent placement for chronic iliofemoral venous obstruction to be likely to help selected patients, but the risks and benefits have not been fully quantified in well-designed randomized studies. SIR recommends urgent completion of such studies. In the meantime, careful patient selection and optimization of conservative therapy are recommended prior to stent placement, with attention to appropriate stent sizing and quality procedural technique. The use of multiplanar venography with intravascular ultrasound is suggested in diagnosing and characterizing obstructive iliac vein lesions and in guiding stent therapy. After stent placement, SIR recommends close patient follow-up to ensure optimal antithrombotic therapy, durable symptom response, and early identification of adverse events.

Society of Interventional Radiology Position Statement on the Endovascular Management of Acute Iliofemoral Deep Vein Thrombosis.

PURPOSE: To establish the updated position of the Society of Interventional Radiology (SIR) on the endovascular management of acute iliofemoral deep vein thrombosis (DVT). MATERIALS AND METHODS: A multidisciplinary writing group with expertise in treating venous diseases was convened by SIR. A comprehensive literature search was conducted to identify studies on the topic of interest. Recommendations were drafted and graded according to the updated SIR evidence grading system. A modified Delphi technique was used to achieve consensus agreement on the recommendation statements. RESULTS: A total of 84 studies, including randomized trials, systematic reviews and meta-analyses, prospective single-arm studies, and retrospective studies were identified and included in the review. The expert writing group developed 17 recommendations that pertain to the care of patients with acute iliofemoral DVT with the use of endovascular venous interventions. CONCLUSIONS: SIR considers endovascular thrombus removal to be an acceptable treatment option in selected patients with acute iliofemoral DVT. Careful individualized risk assessment, high-quality general DVT care, and close monitoring during and after procedures should be provided.

Safety and Success Rates of Excimer Laser Sheath-Assisted Retrieval of Embedded Inferior Vena Cava Filters.

Importance: Despite historically high rates of use, most inferior vena cava (IVC) filters are not retrieved. The US Food and Drug Administration safety communications recommended retrieval when the IVC filter is no longer indicated out of concern for filter-related complications. However, failure rates are high when using standard techniques for retrieval of long-dwelling filters, and until recently, there have been no devices approved for retrieval of embedded IVC filters. Objective: To evaluate the safety and success of excimer laser sheath-assisted retrieval of embedded IVC filters. Design, Setting, and Participants: A retrospective, multicenter, clinical cohort study of excimer laser sheath-assisted IVC filter retrievals from 7 US sites was conducted between March 1, 2012, and February 28, 2021, among 265 patients who underwent IVC filter retrieval using the laser. Patients were substratified between a high-volume single center and a multicenter data set. A blinded physician committee adjudicated reported complications and their association with use of the laser. Exposures: Retrieval of IVC filters using excimer laser sheath. Main Outcomes and Measures: The primary safety end point was device-related major complication rate (Society of Interventional Radiology categories C to F, which included any adverse event associated with morbidity or disability that increases the level of care, results in hospital admission, or substantially lengthens the hospital stay). The primary success end point was technical success of IVC filter retrieval. The primary end points were compared with literature-derived, meta-analysis-suggested target performance goals. Results: The single-center experience included 139 participants (mean [SD] age, 52 [16] years; 78 female participants [56.1%]), and the multicenter experience included 126 participants (mean [SD] age, 52 [16] years; 75 female participants [59.5%]). The device-related major complication rate was 2.9% (4 of 139; 95% CI, 0.8%-7.2%; P = .001) for the single-center experience and 4.0% (5 of 126; 95% CI, 1.3%-9.0%; P = .01) for the multicenter experience, both of which were significantly lower than the primary safety performance goal (10%). No major complications were considered to be definitively associated with use of the laser. The technical success rate was 95.7% (133 of 139; 95% CI, 90.8%-98.4%; P = .007) for the single-center experience and 95.2% (120 of 126; 95% CI, 89.9%-98.2%; P = .02) for the multicenter experience, both of which were significantly higher than the primary performance goal (89.4%). Conclusions and Relevance: This cohort study demonstrated high technical success and low complication rates of excimer laser sheath-assisted retrieval of embedded IVC filters in centers with variable case volume and experience, which suggests a wide applicability of the technique with proper training. The excimer laser sheath offers physicians a valuable tool for retrieval of challenging embedded IVC filters.

Endovascular Management of Acute Iliofemoral Deep Vein Thrombosis.

Lower extremity deep vein thrombosis (DVT) is frequently encountered in clinical practice. Postthrombotic syndrome (PTS) is a common sequela of DVT and encompasses a wide variety of symptoms, including severe pain, edema, and ulceration, all of which may contribute to a negative impact on quality of life. Studies have demonstrated that acute thrombosis of the iliofemoral venous segment is correlated with high rates of PTS, increased severity of symptoms, and high rates of thrombus recurrence, despite patients receiving treatment with standard-of-care anticoagulation therapy. Endovascular interventions, including catheter-directed thrombolysis, pharmacomechanical thrombectomy, and mechanical thrombectomy, have generated significant interest as a method for reduction of short-term symptom severity and potential reduction of downstream PTS severity. While there is high-quality evidence evaluating the role of catheter-directed and pharmacomechanical thrombectomy for acute iliofemoral DVT, newer mechanical-only devices that utilize thrombectomy without fibrinolytic medication are less studied. Currently, there are limited data evaluating the efficacy and safety of these treatment modalities, although investigations are ongoing.

Antithrombotic Therapy after Deep Venous Intervention.

Chronic deep venous disease (CVD) can result in significant morbidity and impact on quality of life due to a spectrum of symptoms, including lower extremity edema, venous claudication, and venous ulcers. CVD can be secondary to both thrombotic and nonthrombotic disease processes, including postthrombotic syndrome from prior deep vein thrombosis (DVT) or iliac vein compression syndrome. Endovascular therapy has become a mainstay therapy for CVD patients, with venous stent placement frequently performed. However, the management of anticoagulation following venous stent placement is not well-studied, with no large trials or consensus guidelines establishing an optimal regimen. The current knowledge gap in antithrombotic therapy is magnified by heterogeneity in practice and data collection, along with incomplete reporting in available studies. Furthermore, most published datasets are antiquated in the setting of rapid evolution in technique and technology available for deep venous intervention. Herein, we summarize the current available literature and offer an approach to anticoagulation and antiplatelet management following deep venous intervention for CVD.

A Brief Review of Thrombolytics for Venous Interventions.

Anticoagulation continues to be the mainstay of therapy for the management of venous thromboembolism. However, anticoagulation does not lead to the breakdown or dissolving of the thrombus. In an acute pulmonary embolism, extensive thrombus burden can be associated with a high risk for early decompensation, and in acute deep venous thrombosis, it can be associated with an increased risk for phlegmasia. In addition, residual thrombosis can be associated with chronic thromboembolic pulmonary hypertension and postthrombotic syndrome in a chronic setting. Thrombolytic therapy is a crucial therapeutic choice in treating venous thromboembolism for thrombus resolution. Historically, it was administered systemically and was associated with high bleeding rates, particularly major bleeding, including intracranial bleeding. In the last two decades, there has been a significant increase in catheter-based therapies with and without ultrasound, where lower doses of thrombolytic agents are utilized, potentially reducing the risk for major bleeding events and improving the odds of reducing the thrombus burden. In this article, we provide an overview of several thrombolytic therapies, including delivery methods, doses, and outcomes.