Use of the Gianturco self-expanding stent in stenoses of the superior and inferior venae cavae.

Twenty-eight patients with severe superior and inferior vena cava syndromes were treated with self-expandable Gianturco stents. Nineteen patients responded, seven did not respond, and two were unevaluable. Fourteen of the 19 who responded had complete or near complete resolution of their syndrome, and five had a partial remission. Five of the responders did not derive any benefit from stent placement because of additional problems that led to their death within 3 weeks of the stent placement procedure. The main cause for failure was the relatively weak expansile force of the stent. Complications included stent migrations without untoward effects in one patient, stent misplacement in one patient, fracture of the stent wire in two patients, and hemorrhage that could be attributed to the stent in one patient. This uncontrolled study suggests that caval obstruction syndromes in some patients may be effectively palliated with Gianturco stents.     

Technical problems associated with placement of the Bird's Nest inferior vena cava filter.

Technical problems encountered during percutaneous placement of 165 Bird's Nest filters over 16 months are described. Filter deployment was successful in all patients. Although frequent, the technical problems were all minor with no long-term sequelae. Several problems were inherent to the design of the filter. Other problems related to the patient's anatomy were seen as well. Because deployment of the Bird's Nest filter is more operator-dependent than is deployment of other types of inferior vena cava filters, knowledge of pitfalls and means to avoid problems are particularly important.     

Chronically occluded inferior venae cavae: endovascular treatment

PURPOSE: To report the results of endoluminal recanalization and stent placement in patients with chronic occlusions of the inferior vena cava (IVC). MATERIALS AND METHODS: Seventeen consecutive patients (12 male, five female patients; mean age, 40.6 years; age range, 15-77 years) with chronic IVC occlusions were treated during a 6-year period. The mean duration of symptoms was 32 months. Underlying active malignancy was the cause of occlusion in four patients. Five patients with superimposed acute thrombus underwent catheter-directed thrombolysis prior to IVC recanalization. Clinical patency was defined as absence or improvement of symptoms. Clinical follow-up was supplemented with ultrasonography, vena cavography, or both in 10 patients. RESULTS: Technical success was achieved in 15 (88%) patients. Additional thrombolytic therapy and stent placement was needed in two patients to maintain patency at 4 and 6 months after the procedure. Twelve patients had IVCs that remained patent after a mean follow-up of 19 months for a primary patency rate of 80%. The primary assisted patency rate was 87% (13 of 15). There were four deaths owing to underlying disease 6-21 months after the procedures. There were no procedure-related complications. CONCLUSION: Endoluminal recanalization and stent placement in chronically occluded IVCs has a good intermediate-term outcome and should be considered in patients who have symptoms and who often do not have adequate alternative therapy.     

Bird's Nest filter placement within an enlarged hemiazygos vein for prevention of pulmonary embolism

Thrombosis of the inferior vena cava (IVC) may result in considerable enlargement of paravertebral, azygos, and hemiazygos collateral veins that may in turn serve as pathways for thromboemboli to the pulmonary circulation. Herein we describe the transfemoral placement of a Bird's Nest filter within an enlarged hemiazygos vein to provide prophylaxis against pulmonary embolism in a patient with right femoral venous thrombosis who could not tolerate systemic anticoagulation. There had been earlier transjugular placement of a Greenfield filter within the suprarenal IVC.     

Long-term follow-up of the Bird's Nest IVC Filter

AIM: This study is a long-term clinical follow-up of the Bird's Nest Filter which addresses issues such as caval patency, filter integrity, morbidity and mortality. MATERIALS AND METHODS: 78 consecutive patients with Bird's Nest Filters inserted between 1989 and 1994 were recalled for clinical assessment and imaging follow-up. Pre- and post-filter medical histories were obtained from the patients and their medical records. They were examined for clinical signs of inferior vena cava occlusion. Imaging follow-up was by plain abdominal radiography, colour duplex ultrasound and computed tomography. RESULTS: 52 patients were alive and well at 4-6 years. Thirty-day mortality was 5.1%. Three-year mortality was 19.2%. Recurrent pulmonary embolus occurred in 1.3%. IVC occlusion was demonstrated in 4.7%. No evidence of filter migration was seen. Wire prolapse occurred in 70% on abdominal X-ray and asymptomatic performation of the caval wall in 85.3% on CT. Morbidity and mortality were the same whether the patient was anticoagulated or not. CONCLUSION: The Bird's Nest Filter is safe and effective in both the short and long term.     

Prevalence of local venous thrombosis after transfemoral placement of a Bird's Nest vena caval filter

Bird's Nest vena caval filters were placed in 63 patients over a 6-month period by means of a transfemoral (n = 62) or transjugular (n = 1) approach. To determine the prevalence of access-site thrombosis, compression color Doppler flow imaging was performed 1-11 days after the procedure in 48 patients without suspected or documented preexisting thrombus. Clinical follow-up was from 5 to 289 days (mean, 100 days). Findings at ultrasound (US) examination were normal in 38 patients, and all of these patients remained clinically asymptomatic. Nonocclusive thrombus was seen in nine patients, eight of whom remained asymptomatic. A single patient had an occlusive thrombus at US. This patient had leg swelling. Nonocclusive thrombus did not predispose patients to the development of clinically evident occlusive thrombosis. The authors conclude that the transfemoral placement of the Bird's Nest vena caval filter is associated with a low prevalence (2%) of femoral vein occlusion documented at US follow-up. This contrasts with results from a similarly designed study demonstrating a 17% prevalence after percutaneous Greenfield filter placement.     

Penetration of a fractured Bird's Nest filter strut into the liver parenchyma: report of two cases

This report deals with two rare but similar cases of asymptomatic fracture of a Bird's Nest inferior vena cava (IVC) filter strut, penetrated into the liver parenchyma. Follow-up over 4 and 6 years, respectively, could not reveal any changes in the position of the fragmented strut in the liver parenchyma or any evidence of clinical symptoms owing to the migrated strut fragment.     

Left femoral vein approach for the percutaneous placement of the Bird's Nest Filter

The Bird's Nest Filter femoral catheter set has proven to be too short in some patients to permit placement in close proximity to the renal veins via the left femoral vein approach. The use of the longer, but otherwise identical Bird's Nest Filter jugular catheter set via the left femoral vein eliminates this problem.     

Congenital anomalies of the venae cavae: embryological origin,imaging features and report of three new variants

Due to the complexity of their developmental stages, the venae cavae may undergo a very large number of congenital anomalies. All the possible abnormalities which, to our knowledge, have been observed in the literature are reported, differentiating those of the superior vena cava and the azygos system, those of the inferior vena cava and the complex anomalies that concern the venous system as a whole. Moreover, we present three new variants: a right double inferior vena cava with azygos continuation of the posterior-medial vein; an agenesis of the superior vena cava with drainage through the azygos and hemiazygos veins to the inferior vena cava; and a double inferior vena cava with hemiazygos and azygos continuation of the left one.     

经皮穿刺下腔静脉滤器置入术

目的 评价下腔静脉滤器预防肺动脉血栓栓塞的作用。方法 ２８例下肢深静脉血栓形成患者实施了经皮穿刺下腔静脉小 置入术,２６例置入岛巢式滤器,２例置入Ｓｉｍｏｎ Ｎｉｔｉｎｏｌ滤器。结果 滤器全部置入肾静脉下方的下腔静脉内。２７例随访２￣３４个月,滤器无移位,１５例不伴有肺动脉血栓栓塞者无肺栓塞发生。结论下腔静脉滤器用于预防肺动脉血栓栓寒是一种安全有效的方法。     

Experience with the recovery filter as a retrievable inferior vena cava filter

PURPOSE: This study evaluates clinical experience with the Recovery filter as a retrievable inferior vena cava (IVC) filter. MATERIALS AND METHODS: One hundred seven Recovery filters were placed in 106 patients with an initial clinical indication for temporary caval filtration. Patients were followed up to assess filter efficacy, complications, eventual need for filter removal, time to retrieval, and ability to remove the filter. RESULTS: The patient cohort consisted of 62 men and 44 women with a mean age of 48 years (range, 18-90 y). Mean implantation time was 165 days. Indications for filter placement in patients with deep vein thrombosis (DVT) and/or pulmonary embolism (PE) included contraindication to anticoagulation (n = 33), complications of anticoagulation (n = 8), poor cardiopulmonary reserve (n = 6), large clot burden (n = 3), and PE while receiving anticoagulation (n = 1). Indications for filter placement in patients without proven PE or DVT included immobility after trauma (n = 35); recent intracranial hemorrhage, neurosurgery, or brain tumor (n = 18); and other surgical or invasive procedure (n = 3). Three patients (2.8%) had symptomatic PE after placement of the Recovery filter. No caval thromboses were detected. No symptomatic filter migrations occurred. Recovery filter removal was attempted in 15 of 106 patients (14%) at a mean of 150 days after placement. The Recovery filter was successfully retrieved in 14 of 15 patients (93%); one removal was unsuccessful at 210 days after placement. Ninety-two filters (87%) currently remain in place. CONCLUSIONS: Although all the filters were placed with the intention of being removed, a large percentage of filters were not retrieved. The Recovery filter was safe and effective in preventing PE when used as a retrievable IVC filter.     

The Simon nitinol inferior vena cava filter: preliminary experience in the UK.

The Simon nitinol filter is one of a new range of inferior vena cava filters designed for percutaneous placement. It employs a thermal memory alloy allowing it to be introduced in a straight form via a 9F sheath when cool but transforming instantly into its predetermined filter shape at body temperature. It was placed rapidly and successfully in six patients via a femoral approach and one patient via an antecubital vein. The only complication was an asymptomatic IVC obstruction in one patient.