Use of noncontrast computed tomography of the inferior vena cava for real-time imaging guidance for the placement of inferior vena cava filters.
ABSTRACT: Appropriate placement of an inferior vena cava (IVC) filter necessitates imaging of the renal veins because when an IVC filter is deployed its tip should be at or below the inferior aspect of the inferiormost renal vein. Traditionally, imaging during placement of IVC filters has been with conventional cavography and fluoroscopy. Recently, intravascular ultrasound has been used for the same purpose but with additional expense. Morbidly obese patients often exceed the weight limit of fluoroscopy tables. In addition, short obese patients are at risk of falling from narrow fluoroscopy tables. For such patients, computed tomography (CT) guidance is a viable alternative to conventional fluoroscopic guidance. IVC placement was performed in the CT suite for two obese patients who exceeded the weight limits of the available fluoroscopy tables. In one case, a Vena-Tech filter (Braun Medical, Melsungen, Germany) was placed using CT fluoroscopy. In the second case, a Recovery (Bard, Murray Hill, NJ) filter was placed using intermittent limited z-axis scanning. In the first case, the filter was placed below the level of the renal veins and above the confluence of the iliac veins, which is acceptable placement. In the second case, with refinement of technique, the filter tip was placed less than 1 cm below the inferiormost renal vein, which is considered optimal placement. CT of the IVC precisely images the renal veins and can characterize their number and their confluence with the IVC. CT guidance is a viable alternative to fluoroscopic guidance for the placement of IVC filters in morbidly obese patients.
Project description:Our study objective was to describe the frequency, indications, and outcomes after inferior vena cava (IVC) filter placement in a population-based sample of residents of the Worcester, Massachusetts, metropolitan area who had been diagnosed as having acute venous thromboembolism (VTE) in 1999, 2001, and 2003.A retrospective chart review of inpatient and outpatient medical records was conducted. Recorded indication(s) for IVC filter placement was determined among a subset of cases from 3 Worcester tertiary care hospitals. Three thrombosis specialists assessed the appropriateness of IVC filter placement.Of 1547 greater Worcester residents with validated acute VTE and without a prior IVC filter, 203 (13.1%) had an IVC filter placed after acute VTE. Patients with an IVC filter were older, had more comorbidities, and had a higher mortality rate during 3 years of follow-up. There was unanimous agreement by panel members that the use of an IVC filter was appropriate in 51% of cases and inappropriate in 26% of cases, with no consensus in the remaining 23%.In this community-based study, IVC filters were frequently used in the treatment of patients with acute VTE. Placement was deemed to be appropriate in approximately 50% of the patients but was not appropriate or debatable in the remaining cases. Given the increasing use of IVC filters, prospective studies are clearly needed to better define the indications for, and efficacy of, IVC filter placement.
Project description:Deep vein thrombosis (DVT) continues to be a significant source of morbidity for surgical patients. Placement of a retrievable inferior vena cava (IVC) filter is used when patients have contraindications to anticoagulation or recurrent pulmonary embolism despite therapeutic anticoagulation. Although retrievable IVC filters are often used, they carry a unique set of risks.A 67-year-old man presents to the Emergency Room (ER) following large volume melena and complaining of syncope. One year prior, the patient had been diagnosed with Glioblastoma multiforme, for which he underwent a craniotomy with near-total resection of the mass. He subsequently developed a deep vein thrombosis and underwent placement of a retrievable inferior vena cava (IVC) filter. Computerized tomography (CT) and esophagogastroduodenoscopy showed duodenal perforation by the retrievable IVC filter. The filter was successfully retrieved through an endovascular approach.Retrievable IVC filter placement is the preferred method of pulmonary embolism prevention in patients with significant risk for bleeding. Duodenal perforation by a retrievable IVC filter is a rare and serious complication. It is usually managed surgically, but can also be managed non-operatively.For patients with significant comorbidities or patients who are poor surgical candidates, non-operative management with close monitoring can serve as an initial approach to the patient with a caval enteric perforation secondary to a retrievable IVC filter.
Project description:PURPOSE:To compare the safety and efficacy of an absorbable inferior vena cava (IVC) filter and a benchmark IVC filter in a porcine model. MATERIALS AND METHODS:A randomized controlled Good Laboratory Practice study was performed in Domestic Yorkshire cross swine. Sixteen swine were implanted with an absorbable IVC filter (test device; Adient Medical, Pearland, Texas); 8 were implanted with a benchmark metal IVC filter (control device; Cook Medical, Bloomington, Indiana). All animals underwent rotational digital subtraction pulmonary angiography and cavography (anteroposterior and lateral) before filter deployment and 5 and 32 weeks after deployment. Terminal procedures and necropsy were performed at 32 weeks. The IVC, heart, lungs, liver, and kidneys were harvested at necropsy. The reported randomized controlled GLP animal study was conducted at Synchrony Labs, Durham, North Carolina. RESULTS:One animal died early in the test cohort of a recurring hemorrhage at the femoral access site resulting from a filter placement complication. All other animals remained clinically healthy throughout the study. No pulmonary embolism was detected at the 5- and 32-week follow-up visits. The absorbable filter subjects experienced less caval wall perforation (0% vs 100%) and thrombosis (0% vs 75%). The control device routinely perforated the IVC and occasionally produced collateral trauma to adjacent tissues (psoas muscle and aorta). The veins implanted with the absorbable filter were macroscopically indistinguishable from normal adjacent veins at 32 weeks except for the presence of radiopaque markers. Nontarget tissues showed no device-related changes. CONCLUSIONS:Implantation of the absorbable IVC filter in swine proved safe with no pulmonary emboli detected. There was complete to near-complete resorption of the filter polymer by 32 weeks with restoration of the normal appearance and structure of the IVC.
Project description:Background:Misplacement of central venous catheters (CVC) may have devastating consequences. Patients and methods:Placement of a CVC into the pulmonary artery (PA) and management of the complication is described. Literature search for accidental direct placement of CVCs into the PA was performed. Results:A 46 year old morbidly obese female required an infusaport for chemotherapy. She was anaesthetized and placed in Trendelenburg. Three attempts to access the left subclavian vein (LSCV) using landmarks failed. In steeper Trendelenburg, a blood vessels was accessed. Non pulsatile dark blood was aspirated, a guidewire was easily advanced. Fluoroscopy projected the guidewire tip over the right atrium; infusaport placement was without difficulties. Postoperative chest x-ray showed the tube initially pointing caudally, then traversing the midline with the tip projecting over the right atrium. Emergent angiogram showed placement of the tube into the mainstem of the PA. The tube was removed; CT-angiogram showed no extravasation but a 3cm left mediastinal hematoma. Transfer to an ICU in a facility offering emergent cardiothoracic surgery was done. She remained stable, repeat CT-scan showed decreased hematoma size and she was retransferred. The infusaport was placed under ultrasound guidance into the left jugular vein. Six additional cases of direct puncture of the PA were reported; in all except one the LSCV had been targeted. No patient died directly from the complication, all catheters were removed, four patients required surgery or interventional procedures. Conclusions:Accidental placement of CVC s into the PA is a rare complication. The catheter should be removed. Patients should be urgently transferred to a center with access to interventional radiology and cardiothoracic surgery.
Project description:A 45-year-old man, who was implanted with an inferior vena cava (IVC) filter in his infrarenal IVC, had a complication of deep vein thrombosis (DVT) propagation from the IVC, beyond the IVC filter, to the right calf and left external iliac veins. The entire IVC filter was covered with a massive thrombus. We first decided to retrieve the IVC filter itself, which was suspected of causing metallic allergy. The thrombotic IVC filter was successfully retrieved using multi-step catheter intervention. To our knowledge, this is the first case report to describe successful multi-step catheter intervention for retrieval of an IVC filter covered with a massive thrombus. <Learning objectives: Inferior vena cava (IVC) filter thrombosis is one of the most serious IVC filter complications. It is difficult to retrieve the IVC filter covered with a massive thrombus. Multi-step catheter intervention technique may be useful to retrieve an IVC filter with thrombotic occlusion.>.
Project description:This case describes a 57-year-old morbidly obese woman with complications of a permanent Bard inferior vena cava (IVC) filter (BD Bard, Covington, Ga) placed in 2005. She complained of recurrent abdominal pain for 6 years associated with constipation, nausea, and bloating. Computed tomography venography showed an IVC filter with malposition, strut fracture, and extrusion, and a fractured strut protruded outside of the vena cava, adjacent to the distal right common iliac artery. The da Vinci Xi Surgical System (Intuitive Surgical, Sunnyvale, Calif) was used to remove the IVC filter and its displaced fractured strut. The operation time was 189 minutes, with an estimated blood loss of 200 mL. She was discharged home on postoperative day 2 with no complications. She had complete resolution of abdominal pain at her follow-up appointment.
Project description:Abstract <h4>Background</h4> Spontaneous iliac vein ruptures have only been reported in approximately 50 cases. An accurate preoperative diagnosis is difficult even with contrast-enhanced computed tomography (CT), and the operative mortality and morbidity rates are quite high. The cause of spontaneous iliac vein ruptures and their optimal diagnosis and management remain unclear. <h4>Case summary</h4> A 69-year-old woman without a history of prior trauma presented with low back pain, left lower limb swelling, and hypovolaemic shock. An initial contrast-enhanced CT revealed a large retroperitoneal haematoma without arterial extravasation. Her blood pressure dropped again under a noradrenaline administration. A second venous phase contrast-enhanced CT revealed venous extravasation in the external iliac vein with a suspected compression of the common iliac vein (May–Thurner syndrome) and deep vein thrombosis (DVT). Her haemodynamics were stabilized whilst a laparotomy was arranged. An inferior vena cava (IVC) filter was placed due to concerns about rebleeding with initiating anticoagulation therapy. Given the failed conservative management, elective endovascular treatment (EVT) was performed including percutaneous Fogarty venous thrombectomy and placement of self-expanding and covered stents. After the intervention, the lower limb swelling significantly improved under oral anticoagulation therapy, and the IVC filter was retrieved. At the 3-month follow-up, the lower limb swelling completely disappeared, and the contrast-enhanced CT demonstrated the complete disappearance of the retroperitoneal haematoma and DVT. <h4>Discussion</h4> This case provided not only the potential value of the venous phase contrast-enhanced CT in diagnosing a spontaneous iliac vein rupture but also the potential benefit of conservative management followed by elective EVT.
Project description:<h4>Importance</h4>Venous thromboembolism is the second overall leading cause of death for patients with cancer, and there is an approximately 2-fold increase in fatal pulmonary embolism (PE) in patients with cancer. Inferior vena cava (IVC) filters are designed to prevent PE, but defining the appropriate use of IVC filters in patients with cancer remains a substantial unmet clinical need.<h4>Objective</h4>To evaluate the association of IVC filters with the development of PE in patients with cancer and deep venous thrombosis (DVT).<h4>Design, setting, and participants</h4>A population-based cohort study was conducted using administrative data on 88 585 patients from the state inpatient databases for California (2005-2011) and Florida (2005-2014). Based on diagnostic and procedure codes, patients with cancer and acute lower extremity DVT were identified. All subsequent hospital visits for these patients were evaluated for the placement of an IVC filter, the development of new PE, the development of new DVT, and in-hospital mortality. Data analysis was performed from September 1 to December 1, 2019.<h4>Exposures</h4>Placement of an IVC filter.<h4>Main outcomes and measures</h4>The association of IVC filter placement with rates of new PE and DVT was estimated using a propensity score matching algorithm and competing risk analysis.<h4>Results</h4>The study cohort comprised 88 585 patients (45 074 male; median age, 71.0 years [range, 1.0-104.0 years]) with malignant neoplasms who presented to a health care institution with a diagnosis of acute lower extremity DVT. Of these patients, 33 740 (38.1%) underwent IVC filter placement; patients with risk factors such as upper gastrointestinal bleeding (odds ratio, 1.32; 95% CI, 1.29-1.37), intracranial hemorrhage (odds ratio, 1.21; 95% CI, 1.19-1.24), and coagulopathy (odds ratio, 1.09; 95% CI, 1.08-1.10) were more likely to receive an IVC filter. A total of 4492 patients (5.1%) developed a new PE after their initial DVT diagnosis. There was a significant improvement in PE-free survival for these patients compared with those who did not receive IVC filters across the full, unbalanced study cohort as well as after propensity score matching and competing risk analysis (hazard ratio, 0.69; 95% CI, 0.64-0.75; P < .001). Furthermore, IVC filter placement reduced the development of PE in patients with very high-risk malignant neoplasms (eg, pancreaticobiliary cancer), high-risk malignant neoplasms (eg, lung cancer), and low-risk malignant neoplasms (eg, prostate cancer). After accounting for anticoagulation use and imbalanced risk factors, IVC filter placement did not increase the risk of new DVT development.<h4>Conclusions and relevance</h4>This study suggests that, for patients with cancer and DVT and bleeding risk factors, IVC filter placement is associated with an increased rate of PE-free survival.
Project description:The role of inferior vena cava filter (IVC) filters for prevention of pulmonary embolism (PE) is controversial. This study evaluated outcomes of IVC filter placement in a managed care population. This retrospective cohort study evaluated data for individuals with Humana healthcare coverage 2013-2014. The study population included 435 recipients of prophylactic IVC filters, 4376 recipients of therapeutic filters, and two control groups, each matched to filter recipients. Patients were followed for up to 2 years. Post-index anticoagulant use, mortality, filter removal, device-related complications, and all-cause utilization. Adjusted regression analyses showed a positive association between filter placement and anticoagulant use at 3 months: odds ratio (ORs) 3.403 (95% CI 1.912-6.059), prophylactic; OR, 1.356 (95% CI 1.164-1.58), therapeutic. Filters were removed in 15.67% of prophylactic and 5.69% of therapeutic filter cases. Complication rates were higher with prophylactic procedures than with therapeutic procedures and typically exceeded 2% in the prophylactic group. Each form of filter placement was associated with increases in all-cause hospitalization (regression coefficient 0.295 [95% CI 0.093-0.498], prophylactic; 0.673 [95% CI 0.547-0.798], therapeutic) and readmissions (OR 2.444 [95% CI 1.298-4.602], prophylactic; 2.074 [95% CI 1.644-2.616], therapeutic). IVC filter placement in this managed care population was associated with increased use of anticoagulants and greater healthcare utilization compared to controls, low rates of retrieval, and notable rates of device-related complications, with effects especially pronounced in assessments of prophylactic filters. These findings underscore the need for appropriate use of IVC filters.
Project description:Background Pulmonary embolus (PE) remains a leading etiology of maternal mortality in the developed world. Increasing utilization of retrievable inferior vena cava (IVC) filter placement currently includes pregnant patients. Case A 22-year-old woman at 27 weeks' gestation was diagnosed with Stage IV high-grade malignant B cell lymphoma following pathologic femur fracture. Significant risk factors for PE led to placement of primary prophylaxis IVC filter before cesarean delivery, open reduction and internal fixation of the fractured femur, and chemotherapy. Conclusion This case supports that primary prophylaxis placement of IVC filters in highly selected pregnant patients may assist in decreasing PE-associated maternal mortality.