Endovascular thrombectomy and repair of suprarenal inferior vena cava thrombosis: A case series.

OBJECTIVES: The objective of this study is to document the combined use of catheter-based thrombectomy/thrombolysis with endovascular repair of high-risk segments of the inferior vena cava in the setting of iatrogenic and traumatic injuries. While the use of endovascular techniques to treat caval thrombosis is well documented and often preferred due to its minimally invasive nature, there is still little literature that focuses on the nuances related to injury of high mortality areas of the IVC as a result of major trauma, transplant, and other surgical interventions. METHODS: An IRB-approved retrospective review of all patients undergoing IVC thrombectomy was performed at a single tertiary care academic center between January 2018 and July 2021. Cases were subsequently selected based on those who underwent primary mechanical thrombectomy followed by endovascular stenting (or angioplasty). Among this cohort, four patients who underwent this procedure in the context of iatrogenic and traumatic injuries were included. RESULTS: All four patients undergoing primary mechanical thrombectomy followed by endovascular stenting (or angioplasty) due to IVC thrombus and/or stenosis were technically successful with immediate positive clinical outcomes. CONCLUSIONS: Mechanical thrombectomy in conjunction with IVC recanalization via stenting may be a useful intervention with promising technical success and positive clinical outcomes for occlusive thrombosis and IVC stenosis.

Hybrid CT-angiography to facilitate lower extremity sharp venous recanalization: a novel approach to a common procedure.

BACKGROUND: Post-thrombotic syndrome due to chronic venous occlusion is associated with high morbidity and healthcare costs. Sharp venous recanalization has been used with success when conventional techniques fail to cross the occlusion, permitting endovascular reconstruction with angioplasty and stenting. However, manipulation of a needle, especially in extra-anatomic locations, risks damage to adjacent structures, thus necessitating adequate imaging guidance. CASE PRESENTATION: This report describes the novel use of hybrid CT-angiography in a successful recanalization of a complex iliofemoral chronic venous occlusion, after multiple failed attempts with traditional recanalization techniques. The procedure was performed without complications, and stent patency was confirmed at three-month follow-up with patient-reported improvement in severe post-thrombotic syndrome. CONCLUSIONS: This case demonstrates effective incorporation of hybrid CT-angiography to facilitate complex sharp venous recanalization for chronic lower extremity thrombosis, as an alternative to standard fluoroscopic techniques requiring multiple projections with or without cone-beam CT. Further studies are needed to understand the implications of this strategy.

Percutaneous treatment of IVC obstruction due to post-resection hepatic torsion associated with IVC thrombosis.

BACKGROUND: Migration of the left hepatic lobe into the potential space following right lobe resection can result in torsion and hepatic venous outflow obstruction with compromised venous return from the IVC. If untreated, significant morbidity and mortality can develop. CASE PRESENTATION: We report a case of a 29-year-old female with Lynch syndrome who underwent right lobe resection for a metastatic hepatic tumor. There was subsequent migration of the liver remnant, torsion of the IVC, and impaired hepatic outflow, successfully treated with thrombectomy and stenting. CONCLUSION: Following right hepatectomy, hepatic venous outflow obstruction should be consdered in the setting of hepatorenal failure and hemodynamic instability. Endovascular stenting is a viable treatment option.

Catheter-Directed Fibrinolysis of Submassive Pulmonary Embolism After IVC Filter Migration to Renal Veins.

A 76-year-old male presented with a submassive pulmonary embolism despite having an inferior vena cava (IVC) filter. Imaging demonstrated pulmonary artery emboli and a deep vein thrombosis in the left common femoral vein. Venography revealed the IVC filter with struts extending into the left and right renal veins. A new IVC filter was deployed below the prior filter. This case demonstrates IVC filter migration complicated by a submassive pulmonary embolism.

Indwelling and Retrieval Complications of Denali and Celect Infrarenal Vena Cava Filters.

PURPOSE: To compare indwelling and retrieval complications of Denali and Celect filters placed in the infrarenal inferior vena cava (IVC). MATERIALS AND METHODS: A retrospective study was conducted over 2 years at a single institution in which 171 Denali and 162 Celect filters were placed in 333 patients with a mean age of 62.3 years ± 15.7 (161 men; 48.3%). Filter indications included venous thromboembolic disease (n = 320; 96.1%) and surgical prophylaxis (n = 13; 3.9%). A jugular approach was used to place 303 filters (91.0%). Computed tomography (CT) follow-up, complications, and retrieval data were obtained. RESULTS: Follow-up CT imaging was performed on 58 filters from each group with lower incidences of caval strut penetration (one vs 12) and filter tilt (one vs 15) in the Denali filter group (P = .002 and P < .001, respectively). There was no difference in incidences of breakthrough pulmonary embolism (P = .68). Retrieval attempts were performed on 43 Denali and 53 Celect filters with mean indwelling times at retrieval of 128.2 and 144.1 days, respectively (P = .40). Mean fluoroscopy time at retrieval was lower in the Denali group (3.1 min vs 6.0 min; P = .01). There were fewer cases of complex retrieval in the Denali group (n = 2 vs 10; P = .06). Tilt, fluoroscopy time, and air kerma were associated with complex retrieval (P = .04, P < .001, and P < .001, respectively). There was one Denali filter deployment complication that led to retrieval failure. CONCLUSIONS: This study suggests that Denali filters are associated with lower incidences of strut penetration and filter tilt as well as shorter fluoroscopy time at retrieval compared with Celect filters when placed in the infrarenal IVC.

Evaluation and treatment of suspected type II endoleaks in patients with enlarging abdominal aortic aneurysms.

PURPOSE: To evaluate angiographic diagnosis and embolotherapy of patients with enlarging abdominal aortic aneurysms and computed tomographic (CT) diagnosis of type II endoleak. MATERIALS AND METHODS: A retrospective review was performed of all patients referred to a single vascular and interventional radiology section from January 1, 2003, to June 1, 2011, with a diagnosis of enlarging aneurysm and type II endoleak. Twenty-five patients underwent 40 procedures between 12 and 82 months after endograft insertion (mean, 48 mo) for diagnosis and/or treatment of endoleaks. RESULTS: Type II endoleaks were treated with cyanoacrylate, coils, and ethylene vinyl alcohol copolymer in 16 patients. Technical success rate was 88% (14 of 16 patients) and clinical success rate was 100% (16 of 16 patients). Aneurysm growth was arrested in all cases over a mean follow-up of 27.5 months (range, 6-88 mo). Endoleaks in nine patients were misclassified on CT; two had type I endoleaks and seven had type III endoleaks. Four of the nine patients (two type I endoleaks and two type III endoleaks) were correctly classified after initial angiography. The other five type III endoleaks were correctly classified on CT after coil embolization of the inferior mesenteric artery. Direct embolization was performed via sac puncture with ethylene vinyl alcohol copolymer in two of the latter five patients and eliminated endoleaks in both. CONCLUSIONS: Aneurysm growth caused by type II endoleaks was arrested by embolization. CT misclassification occurred relatively commonly; type III endoleaks purported to be type II endoleaks were found in 28% of patients (seven of 25).

Iatrogenic portobiliary fistula treated by stent-graft placement.

Stent-graft exclusion of an ischemic, hilar portobiliary fistula after liver transplantation has not been reported. Isolated reports have described peripheral or nonischemic fistulas, and alternative treatment options have ranged from balloon tamponade to surgical repair. We present a unique case of a hilar portobiliary fistula successfully treated to resolution by unilateral placement of a stent-graft.

Embolization of postsurgical obturator artery pseudoaneurysm.

The anatomy of the obturator artery in the pelvis makes this vessel and its branches prone to iatrogenic injury during pelvic surgery. We present a postoperative obturator artery pseudoaneurysm treated by transcatheter embolization. Normal and variant obturator vascular anatomy, as well as pathology related to traumatic injury of this vessel, are subsequently discussed.

Percutaneous treatment of venous outflow obstruction in pediatric liver transplants.

PURPOSE: To evaluate the efficacy and safety of percutaneous dilation in the treatment of impaired venous outflow in pediatric patients with liver transplants. MATERIALS AND METHODS: Review was undertaken of the records of 35 procedures to dilate impaired venous outflow in 16 consecutive children (aged 11 days to 17.8 years; mean, 7.2 +/- 5.8 y) after liver transplantation over a period of 8 years. Patients presented clinically with signs or symptoms of obstruction of the hepatic venous or inferior vena cava anastomosis and/or abnormal noninvasive imaging findings and were referred primarily to the interventional radiology department for treatment. None were excluded. Technical and clinical success rates were calculated. After venoplasty, patients with incomplete venographic resolution or pressure gradients exceeding 5 mm Hg were treated with stents. Seven died or required repeat transplantation during the study period for reasons unrelated to venous outflow obstruction. Patency rates were calculated for all other patients with sufficient follow-up in the pediatric hepatology clinic. RESULTS: The combined technical success rate for venoplasty (12 of 16) and stent placement (three of 16) was 94% (15 of 16), and the clinical success rate was 81% (13 of 16). One minor complication occurred: a transient hypoxic episode. Primary patency rates were 72.7% (eight of 11) at 3 months, 60% (six of 10) at 6 months, 55.6% (five of nine) at 12 months, 50% (four of eight) at 18 months, and 50% (three of six) at 36 months. Primary assisted and secondary patency rates were 90.9% (10 of 11) at 3 months, 90% (nine of 10) at 6 months, 88.9% (eight of nine) at 12 months, 87.5% (seven of eight) at 18 months, and 83.3% (five of six) at 36 months. CONCLUSIONS: Excellent technical and clinical success rates can be achieved with percutaneous dilation of impaired venous outflow after pediatric liver transplantation. Long-term patency may require repeated interventions.

Balloon dilatation of biliary-enteric strictures in children.

OBJECTIVE: The objective of our study was to evaluate the efficacy and safety of balloon dilatation in the treatment of anastomotic strictures in children with liver transplants. MATERIALS AND METHODS: For a period of 7 years, we treated 20 consecutive biliary-enteric strictures in 19 children (age range, 13 months to 17.9 years, mean, 7.3 years) with balloon dilatation. Dilatation was performed between 30 days and 8.4 years (mean, 2.6 years) following surgical creation of the biliary-enteric anastomosis. Thirteen patients had left lateral segment liver transplant grafts, one patient had a split-liver, left-lobe graft, and five patients had whole liver grafts. RESULTS: Technical success was 100% and there were no procedure-related complications. One patient with a patent anastomosis underwent repeat transplantation 183 days after the procedure for chronic rejection. In 58% (11/19) of the remaining procedures, balloon dilatation resulted in biliary-enteric patency at one year, and continued patency ranges from 1.4 to 5.4 years (mean, 3.6 years). In 40% (8/20) of the procedures, the biliary-enteric stricture persisted after balloon dilatation, and these patients eventually underwent surgical revision, retransplantation, or endobiliary metallic stent placement. CONCLUSION: Balloon dilatation is a safe and effective treatment for biliary-enteric strictures following pediatric liver transplantation.

Long-term venous complications after full-size and segmental pediatric liver transplantation.

OBJECTIVE: To assess the long-term incidence of venous complications, including portal vein and hepatic vein stenoses, in both whole cadaveric and reduced-size cadaveric and living related liver transplants in a pediatric population, and to assess the therapeutic modalities in the treatment of these lesions. SUMMARY BACKGROUND DATA: A shortage in appropriate-sized liver grafts for pediatric patients led to the use of segmental liver grafts, which became the predominant graft used in 325 of 600 (54%) transplants at the authors' institution. To assess the long-term impact of this strategy, the authors examined the incidence of late (>90 days) venous complications and the efficacy of all therapeutic interventions. METHODS: Six hundred pediatric liver transplants were performed in 325 patients, with reduced-size or split (RSS; n = 207), living related (LRD; n = 118), or full-size cadaveric grafts (FS; n = 275) from 1988 to 2000. All transplants identified with late portal vein or vena caval stenoses or thromboses from a cohort of 524 grafts with survival greater than 90 days were reviewed for demographics, symptoms, therapeutic intervention, recurrence, morbidity, and mortality. RESULTS: Fifty lesions were identified in 49 patients (38 portal vein and 12 hepatic vein-cava stenoses). Sex distribution was similar between portal vein and hepatic vein to cava, as was the mean patient age. Portal vein stenoses occurred in 32 LRD, 3 RSS, and 3 FS, while hepatic vein-cava stenoses occurred in 2 LRD, 8 RSS, and 2 FS. In the 38 portal vein stenoses, 9 had prior perioperative portal vein and/or 5 hepatic artery thrombectomies. Portal vein stenoses were identified after bleeding (17/38), ascites (6/38), increased liver function tests (6/38), splenomegaly (5/38), or screening ultrasound (4/38). Portal vein stenosis was associated most often with cryopreserved vein for portal conduits. Excluding conduits, the incidence of late portal vein complications was reduced to 1%. Lesions became symptomatic at a mean of 50.8 +/- 184.2 months posttransplant. All patients underwent venous angioplasty with a 66% (25/38) success rate, while 7 of 25 required further angioplasty and stenting. In the 13 unsuccessful angioplasties, 8 required surgical shunts for complete portal vein thrombosis. Recurrence occurred in 9 patients: all were amenable to stenting. Nine patients (24%) eventually died of sepsis (4) and surgical deaths at shunt or retransplant (5). Hepatic vein-cava stenoses occurred after a mean of 37.2 +/- 35.2 months, presenting with ascites (n = 10), increased liver function tests (n = 2), and splenomegaly (n = 2). All patients were diagnosed by venogram and managed by balloon dilatation alone (n = 6) or stented (n = 4), with an 80% (10/12) success, with two late recurrences amenable to repeat angioplasty or stenting. Long-term survival was 80% at 1 year. CONCLUSIONS: The use of segmental grafts without venous conduits is not associated with a significant rate of long-term venous complication. When late venous complications do occur, venous angioplasty and stenting are both a safe and effective management modality. If necessary, venous angioplasty may be repeated with the placement of a stent. When this is required, care must be taken to place the stent in a position where the metallic object will not interfere with future surgical manipulations should retransplantation be necessary.

Using pullback pressure measurements to identify venous stenoses persisting after successful angioplasty in failing hemodialysis grafts.

OBJECTIVE: We used pullback pressure measurements to identify venous stenoses persisting after angioplasty of failing hemodialysis grafts. MATERIALS AND METHODS: Fifty angioplasty procedures were performed in 32 patients with elevated venous pressures at dialysis. Grafts were initially evaluated on digital subtraction angiography, and all stenoses measuring greater than 50% on angiography underwent angioplasty. In successful cases (residual stenosis < 30%), pullback pressure measurements were obtained from the superior vena cava to the graft to identify hemodynamically significant (> 10 mm Hg) stenoses. These lesions were then treated with repeated angioplasty. RESULTS: Hemodynamically significant stenoses with a gradient range of 10-27 mm Hg (mean, 16 mm Hg) were found in nine (18%) of 50 procedures. All gradients occurred at sites of previous angioplasty. Repeated angioplasty of these stenoses performed with larger angioplasty balloons reduced gradients to less than 3 mm Hg in six stenoses and to 5 mm Hg in three stenoses. In this subgroup, primary patency was eight (89%) of nine stenoses at 1 month and 2 months and five (56%) of nine stenoses at 6 months. Using life table analysis, we found that primary patency of the entire population was 84% at 1 month, 66% at 2 months, and 47% at 6 months. The mean time between interventions was 6 months, and the thrombosis rate was 0.32 per year. CONCLUSION: Pullback pressure measurements are a useful adjunct to angiography to evaluate the hemodynamic results of angioplasty in patients with failing hemodialysis grafts.