Objective: To examine the application effect of the modified wire-loop snare technique in retrieving severely tilted inferior vena cava filters (IVCF). Methods: The clinical data of 18 patients (12 males and 6 females, aged (62.1±13.1) years (range: 29 to 78 years)) who underwent the modified wire-loop snare technique to retrieve IVCF at the Affiliated Hospital of Qingdao University, Qingdao Eighth People's Hospital, and Jimo District Hospital of Traditional Chinese Medicine from November 2017 to April 2022 were retrospectively analyzed. The applied filters included drum-type filters (OptEase in 7 cases, Aegisy in 2 cases) and conical filters (Celect in 6 cases and Denali in 3 cases). Preoperative CT angiography and intraoperative digital subtraction angiography showed that the filter was severely tilted and the hook was covered by hyperplastic intima of the vena cave vein. A modified wire-loop snare technique was used to retrieve drum-type filters and conical filters via femoral and jugular vein approaches, respectively. After successful puncture, the long sheath was placed, the 4 F (1 F≈0.33 mm) vertebral catheter and a snare were inserted through the long sheath, and the 5 F pigtail catheter was inserted simultaneously to guide a 0.035 inch soft guide-wire (260 cm in length) to pass through the top of the filter and turning back. The tip of the soft guide-wire was snared by the vertebral catheter and pulled out of the sheath. The 4 F vertebral catheter was inserted following the tip of the guide-wire to form a wire-loop using the vertebral catheter and the pigtail catheter. After fixing the tip and tail of the soft guide-wire in vitro, the long sheath was pushed forward to cut the hyperplastic intima and the hook was pulled away from the vena cava wall to retrieve the filter under the support of two catheters. Results: The filters were successfully retrieved in 17 cases, the operation time was (25.5±8.7) minutes (range: 15 to 45 minutes), no complication occured. The hook of one filter (Celect) penetrated out of the vena vava wall and the wire-loop could not pull the hook back into the vena cava. Then the filter was removed by laparotomy. Conclusion: The modified wire-loop snare technique could retrieve the severely tilted retrivable drum-type filters and conical filters, even when serve adhesion exists between the filter and the vena cava wall.
Humans ; Vena Cava Filters ; Retrospective Studies

The dynamic analysis of the implantation process of a new vena cava filter was carried out by finite element analysis method to reveal the influence of the angle, length, width and thickness of the filter rod on its mechanical properties and the inner wall of the blood vessel. The results showed that the high-stress and high-strain areas of the filter were mainly concentrated in the connection between the filter rod and the filter wire. With the increase of the angle of the filter rod, the maximum equivalent stress and the maximum elastic strain on the filter wall decreased, while the maximum equivalent stress on the vascular wall increased. With the increase of the length of the filter rod, the maximum equivalent stress and strain peak of the filter wall increased, but the maximum equivalent stress of the vessel wall decreased. With the increase of the width and thickness of the filter rod, the maximum equivalent stress of the filter wall, the maximum elastic strain and the maximum equivalent stress of the vessel wall all showed an upward trend. The static safety factor of all filter models was greater than 1, and the structure after implantation was safe and reliable. The results of this study are expected to provide a theoretical basis for the structural optimization and deformation mechanism of the new type vena cava filter.
Finite Element Analysis ; Vena Cava Filters ; Vena Cava, Inferior

The use of retrievable inferior vena cava (IVC) filters has markedly increased in the recent years. However, the failure rate for the retrieval of the IVC filters using the endovascular method is reported to be up to 19%. Open surgical removal of the IVC filters is technically challenging and may require longitudinal cavotomy, clamping, and repair of the IVC. Here, we present a case of successful open surgical removal of the IVC filter using minimal cavotomy. This technique is an effective method after a failed endovascular removal attempt.
Constriction ; Methods ; Vena Cava Filters ; Vena Cava, Inferior

Vena cava filter is a filter device designed to prevent pulmonary embolism caused by thrombus detached from lower limbs and pelvis. A new retrievable vena cava filter was designed in this study. To evaluate hemodynamic performance and thrombus capture efficiency after transplanting vena cava filter, numerical simulation of computational fluid dynamics was used to simulate hemodynamics and compare it with the commercialized Denali and Aegisy filters, and in vitro experimental test was performed to compare the thrombus capture effect. In this paper, the two-phase flow model of computational fluid dynamics software was used to analyze the outlet blood flow velocity, inlet-outlet pressure difference, wall shear stress on the wall of the filter, the area ratio of the high and low wall shear stress area and thrombus capture efficiency when the thrombus diameter was 5 mm, 10 mm, 15 mm and thrombus content was 10%, 20%, 30%, respectively. Meanwhile, the thrombus capture effects of the above three filters were also compared and evaluated by in vitro experimental data. The results showed that the Denali filter has minimal interference to blood flow after implantation, but has the worst capture effect on 5 mm small diameter thrombus; the Aegisy filter has the best effect on the trapping of thrombus with different diameters and concentrations, but the low wall shear stress area ratio is the largest; the new filter designed in this study has a good filtering and capture efficiency on small-diameter thrombus, and the area ratio of low wall shear stress which is prone to thrombosis is small. The low wall shear stress area of the Denali and Aegisy filters is relatively large, and the risk of thrombosis is high. Based on the above results, it is expected that the new vena cava filter designed in this paper can provide a reference for the design and clinical selection of new filters.
Blood Flow Velocity ; Hemodynamics ; Humans ; Software ; Thrombosis ; therapy ; Vena Cava Filters ; Vena Cava, Inferior

PURPOSE: Surgery is the most common risk factor for pulmonary embolism (PE) in patients with a recent venous thromboembolism (VTE). This study reviewed clinical outcomes of preoperative inferior vena cava filter (IVCF) use in patients with acute VTE during abdominal-pelvic cancer or lower extremity orthopedic surgeries. MATERIALS AND METHODS: We retrospectively analyzed 122 patients with a recent VTE who underwent IVCF replacement prior to abdominal-pelvic cancer or lower extremity orthopedic surgery conducted between January 2010 and December 2016. Demographics, clinical characteristics, postoperative IVCF status, risk factors for a captured thrombus, and clinical outcomes were collected for these subjects. RESULTS: Among the 122 study patients who were diagnosed with acute VTE in the prior 3 months and underwent preoperative IVCF replacement, 70 patients (57.4%) received abdominal-pelvic cancer surgery and 52 (42.6%) underwent lower extremity orthopedic surgery. There were no perioperative complications associated with IVCF in the study population and no cases of symptomatic PE postoperatively. A captured thrombus in the filter was identified postoperatively in 16 patients (13.1%). Logistic regression analysis indicated that postoperative anticoagulation within 48 hours significantly reduced the risk of a captured thrombus (odds ratio [OR], 0.28; 95% confidence interval [CI], 0.08–0.94; P=0.032). CONCLUSION: A captured thrombus in preoperative IVCF was identified postoperatively in 16 patients (13.1%). Postoperative anticoagulation within 48 hours reduces the risk of captured thrombus in these cases.
Demography ; Humans ; Logistic Models ; Lower Extremity ; Orthopedics ; Pulmonary Embolism ; Retrospective Studies ; Risk Factors ; Thrombosis ; Vena Cava Filters ; Vena Cava, Inferior ; Venous Thromboembolism

BACKGROUND AND OBJECTIVES: Neurologic intolerance (NI) is defined as the occurrence of neurological symptoms during carotid artery stenting (CAS). Because NI is inevitable problem, it may be helpful to anticipate its occurrence. So, we studied factors associated with NI during proximal protected CAS. METHODS: We retrospectively analyzed all consecutive patients underwent proximal protected CAS from August 2012 to January 2017. RESULTS: We included total 123 patients (109 males, 72±8 years old). The total procedure time was 43±12 minutes, and mean occlusion time was 4.8±1.2 minutes. We divided CAS patients into 2 groups according to presence of NI; neurologic tolerance (NT; n=74, 60%) and NI (n=49, 40%) groups. After the univariate analysis, symptomatic carotid artery stenosis (p = 0.003), absence of anterior communicating artery (p = 0.015) and low common carotid artery occlusion pressure (CCAOP, p < 0.001) were associated with NI. After the multivariate analysis, NI was significantly associated with symptomatic carotid artery stenosis (odds ratio [OR], 5.549; p = 0.014) and systolic CCAOP≤42 mmHg (OR, 6.461; p < 0.001). In NI group, 43 patients (88%) recovered right after the balloon deflation and 2 patients were normalized within 2 hours. However, 1 had major stroke and 3 had minor strokes in 4 patients with persistent NI ≥24 hours. CONCLUSIONS: About 40% showed NI during the CAS. Most of them (88%, 43 of 49 patients) recovered after the balloon deflation, but stroke incidence was significantly higher in NI group. Symptomatic carotid artery stenosis and systolic CCAOP ≤42 mmHg were significantly associated with the development of NI during proximal protected CAS.
Arteries ; Carotid Arteries ; Carotid Artery, Common ; Carotid Stenosis ; Embolic Protection Devices ; Humans ; Incidence ; Male ; Multivariate Analysis ; Neurologic Manifestations ; Retrospective Studies ; Stents ; Stroke

An 88-year-old woman complained of right quadrant abdominal pain and severe edema in both legs. She had a history of pulmonary embolism one month ago. Abdomen CT showed a huge hepatic cyst compressing the intrahepatic portion of the inferior vena cava (IVC). The venogram CT showed multifocal thrombosis in the iliocaval and both lower extremity veins. Percutaneous hepatic cyst drainage was carried out. Fluid analysis presented leukocytosis, which suggested an infected hepatic cyst. To prevent secondary pulmonary thromboembolism, an IVC filter was inserted before catheter drainage for the hepatic cyst. One week later, abdominal pain was relieved. Then, sclerotherapy for the remnant hepatic cyst was performed by ethanol. Follow-up CT showed an increased amount of thrombosis in the iliocaval and left calf vein, but the IVC filter prevented another thromboembolic event successfully. The patient started dabigatran, a new oral anticoagulant, and compression stockings were applied to both legs. After one month, no visible thrombosis in the pelvis or either extremity was detected in abdominal CT. This case suggests that a huge hepatic cyst, especially with infection, should be considered as a possible cause of deep vein thrombosis if no other risk factors for thromboembolism exist.
Abdomen ; Abdominal Pain ; Aged, 80 and over ; Catheters ; Dabigatran ; Drainage* ; Edema ; Ethanol ; Extremities ; Female ; Follow-Up Studies ; Humans ; Leg ; Leukocytosis ; Liver ; Lower Extremity ; Pelvis ; Pulmonary Embolism ; Risk Factors ; Sclerotherapy ; Stockings, Compression ; Thromboembolism ; Thrombosis ; Tomography, X-Ray Computed ; Veins ; Vena Cava Filters* ; Vena Cava, Inferior* ; Venous Thrombosis*

The retrievable type of inferior vena cava filter has been widely used to prevent pulmonary thromboembolism in patients with deep vein thrombosis and contraindication of anticoagulation. Physicians make considerable efforts to remove the filter according to the manufacturer and US Food and Drug Administration safety advisory recommendation. However, forced filter retrieval might cause vascular injury within 3 weeks. Herein, we report pathologic and angiographic findings to suggest filter associated vascular injury during forced retrieval just within recommended period in a patient with deep vein thrombosis.
Humans ; Pulmonary Embolism ; United States Food and Drug Administration ; Vascular System Injuries ; Vena Cava Filters* ; Venous Thromboembolism ; Venous Thrombosis*

A 20-year-old man presented with a femur fracture and epidural hemorrhage (EDH) following a fall. One month after fracture surgery, swelling developed in both legs, and he was diagnosed as having a deep-vein thrombosis and pulmonary embolism. A retrievable inferior vena cava filter (IVCF) was inserted, because EDH is a contraindication to anticoagulants. Four months later, he complained of abdominal pain, and a computed tomography scan showed a fractured IVCF strut. After percutaneous removal failed 3 times, the IVCF was surgically removed by orthopedists using a portable image intensifier without cardiopulmonary bypass.
Abdominal Pain ; Anticoagulants ; Cardiopulmonary Bypass ; Femur ; Hemorrhage ; Humans ; Leg ; Pulmonary Embolism ; Vena Cava Filters* ; Vena Cava, Inferior* ; Venous Thrombosis ; Young Adult

BACKGROUND: The inferior vena cava filter (IVCF) is very effective for preventing pulmonary embolism in patients who cannot undergo anticoagulation therapy. However, if a filter is placed in the body permanently, it may lead to other complications. METHODS: A retrospective study was performed of 159 patients who underwent retrievable Cook Celect IVCF implantation between January 2007 and April 2015 at a single center. Baseline characteristics, indications, and complications caused by the filter were investigated. RESULTS: The most common underlying disease of patients receiving the filter was cancer (24.3%). Venous thrombolysis or thrombectomy was the most common indication for IVCF insertion in this study (47.2%). The most common complication was inferior vena cava penetration, the risk of which increased the longer the filter remained in the body (p=0.032, Exp(B)=1.004). CONCLUSION: If the patient is able to retry anticoagulation therapy and the filter is no longer needed, the filter should be removed, even if a long time has elapsed since implantation. If the filter cannot be removed, it is recommended that follow-up computed tomography be performed regularly to monitor the progress of venous thromboembolisms as well as any filter-related complications.
Follow-Up Studies ; Humans ; Pulmonary Embolism ; Retrospective Studies ; Thrombectomy ; Thromboembolism ; Vena Cava Filters* ; Vena Cava, Inferior* ; Venous Thrombosis