TIPS: comparison of shunt patency and clinical outcomes between bare stents and expanded polytetrafluoroethylene stent-grafts.

PURPOSE: To compare shunt patency and clinical outcomes in two groups of patients who received a transjugular intrahepatic portosystemic shunt (TIPS): one group with bare stents and one with expanded polytetrafluoroethylene stent-grafts. MATERIALS AND METHODS: TIPS were created with bare stents (n = 41) or stent-grafts (n = 40). Overall TIPS patency rates were compared between these two groups, as were clinical outcomes in patients with variceal bleeding and those with ascites. RESULTS: In the bare stent group, primary shunt patency rates were 63%, 48%, and 24% at 3, 6, and 12 months, respectively. Secondary patency rates were 75% and 62% at 3 and 6 months, respectively. In the stent-graft group, primary patency rates were 94%, 67%, and 38% at 3, 6, and 12 months, respectively. Secondary patency rates were 100% and 92% at 3 and 6 months, respectively. All stent patency rates were higher in the stent-graft group, but only the difference in the 3-month primary patency rate (63% vs 94%) reached significance (P = .03). In patients with variceal bleeding as well as those with ascites, early and overall clinical success rates were higher in the stent-graft group, but only the 3-month and 12-month differences were statistically significant. CONCLUSIONS: TIPS created with stent-grafts had better 3-month primary patency rates and better 3-month and 12-month clinical success rates compared with those created with bare stents.

Suprarenal inferior vena cava filters: a 20-year single-center experience.

PURPOSE: To assess the clinical safety and efficacy of suprarenal inferior vena cava (IVC) filters during long-term follow-up. MATERIALS AND METHODS: In this retrospective study, the authors collected the following data about patients who underwent suprarenal IVC filter placement at their institution between 1988 and 2007: demographics, clinical presentation, indications for filter placement, reasons for placing the filter in the suprarenal IVC, type of filter, frequency of pulmonary embolism (PE) after filter placement, and filter-related problems during follow-up. RESULTS: Seventy patients (32 male and 38 female patients; mean age, 60 years) had suprarenal IVC filters. Sixty-two patients presented with symptoms of venous thromboembolism (VTE) and eight had incidental asymptomatic VTE at imaging. Indications for filter placement were as follows: contraindication to anticoagulation (n = 48), complications and/or failure of anticoagulation (n = 12), added protection (n = 8), and prophylaxis (n = 2). Suprarenal placement was chosen due to IVC thrombus (n = 41), intrinsic and/or extrinsic narrowing of the infrarenal IVC (n = 9), renal and/or gonadal vein thrombus (n = 3), congenital IVC anomalies (n = 6), pelvic mass (n = 5), pregnancy (n = 3), and other reasons (n = 3). The following filters were used: Greenfield (n = 29), Simon Nitinol (n = 5), Vena-Tech (n = 3), TrapEase (n = 22), OptEase (n = 3), Tulip (n = 6), Bird's Nest (n = 1), and Recovery (n = 1). During follow-up (mean, 573 days +/- 953), postfilter PE was suspected in 10 patients; eight patients underwent computed tomography (CT), one of whom had PE at CT. None developed new symptoms of caval thrombosis. Abdominal CT (performed in 30 patients at a mean of 543 days +/- 768) showed thrombus in the filter in three patients, fracture in one patient, and penetration of the IVC wall in two patients. CONCLUSIONS: Suprarenal filters are safe and effective in preventing PE. The placement of IVC filters above the renal veins does not carry an added risk of complications.

"Recovery" vena cava filter: experience in 96 patients.

The purpose of the study was to assess the clinical safety and efficacy of the "Recovery(TM)" (Bard) inferior vena cava (IVC) filter. We retrospectively evaluated the clinical and imaging data of patients who had a "Recovery(TM)" IVC filter placed between January 2003 and December 2004 in our institution. The clinical presentation, indications, and procedure-related complications during placement and retrieval were evaluated. Follow-up computed tomography (CT) examinations of the abdomen and chest were evaluated for filter-related complications and pulmonary embolism (PE), respectively. "Recovery" filters were placed in 96 patients (72 males and 24 females; age range: 16-87 years; mean: 46 years). Twenty-four patients presented with PE, 13 with deep vein thrombosis (DVT) and 2 with both PE and DVT. The remaining 57 patients had no symptoms of thromboembolism. Indications for filter placement included contraindication to anticoagulation (n = 27), complication of anticoagulation (n = 3), failure of anticoagulation (n = 5), and prophylaxis (n = 61). The device was successfully deployed in the infrarenal (n = 95) or suprarenal (n = 1) IVC through a femoral vein approach. Retrieval was attempted in 11 patients after a mean period of 117 days (range: 24-426). The filter was successfully removed in nine patients (82%). Failure of retrieval was due to technical difficulty (n = 1) and the presence of thrombus in the filter (n = 1). One of the nine patients who had the filter removed developed IVC thrombus after retrieval and another had an intimal tear of the IVC. Follow-up abdominal CT (n = 40) at a mean of 80 days (range: 1-513) showed penetration of the IVC by the filter arms in 11, of which 3 had fracture of filter components. In one patient, a broken arm migrated into the pancreas. Asymmetric deployment of the filter legs was seen in 12 patients and thrombus within the filter in 2 patients. No filter migration or caval occlusion was encountered. Follow-up chest CT (n = 27) at a mean of 63 days (range: 1-386) showed PE in one patient (3%). During clinical follow-up, 12 of 96 patients developed symptoms of PE and only 1 of the 12 had PE on CT. There was no fatal pulmonary embolism in our group of patients following "Recovery" filter placement. However, the current version of the filter is associated with structure weakness, a high incidence of IVC wall penetration, and asymmetric deployment of the filter legs.

Renal perfusion defects after endovascular repair of abdominal aortic aneurysms.

PURPOSE: To determine the prevalence of new renal perfusion defects and the association of these events with aneurysm neck atheroma during endovascular stent-graft repair of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: A retrospective review was performed of 50 patients who underwent AAA repair with bifurcated endovascular stent-grafts without suprarenal components between June 1998 and May 1999. Pre- and postprocedural computed tomographic (CT) angiograms were reviewed to determine the prevalence of new renal perfusion defects. The percent volume of atheroma of the aneurysm neck was determined by three-dimensional volumetric reformation and correlated with prevalence of new postprocedural renal perfusion defects. Follow-up CT angiography was performed between 6 months and 2 years after the procedure and used to evaluate the presence of residual defects and interval changes. RESULTS: Of 50 subjects, 18% (n = 9) had new perfusion defects presumed to be embolic in origin. Follow-up was available for four patients: scarring and cortical thinning consistent with infarction developed in two, whereas the defects resolved in the other two. Analysis of aneurysm neck revealed an average percentage of atheroma of 32% and a range of 0%-73%. In subjects with >/=40% neck atheroma, the prevalence of new renal perfusion defects was 45.4% (five of 11), compared to 10.3% (four of 39) in subjects with <40% neck atheroma. This difference was significant (P =.0170). CONCLUSIONS: In this series, the frequency of renal embolic events associated with AAA endovascular repair was 18%. Prevalence of renal embolic perfusion defects was shown to correlate with volume of aneurysm neck atheroma.

Clinical failures of endovascular abdominal aortic aneurysm repair: incidence, causes, and management.

OBJECTIVE: Despite well-documented good early results and benefits of endoluminal stent graft repair of abdominal aortic aneurysm (J Vasc Surg 2002;35:1137-44.)(AAA), the long-term outcome of this method of treatment remains uncertain. In particular, concern exists that late effectiveness and durability are inferior to that of open repair. To determine the incidence and causes of clinical failures of endovascular AAA repair, a 7-year experience with 362 primary AAA endografts was reviewed. METHODS: Clinical failures were defined as deaths within 30 days of the procedure, conversions (early and late) to open AAA repair, AAA rupture after endoluminal treatment, or AAA sac growth of more than 5 mm in maximal diameter despite endograft repair. Endoleak status per se was not considered unless it resulted in an adverse event. If clinical problems arose but could be corrected with catheter-based therapies or limited surgical procedures, thereby maintaining the integrity of successful stent graft treatment of the AAA, such cases were considered as primary assisted success and not classified as clinical failures. RESULTS: The average follow-up period was 1.5 years. Six deaths (1.6%) occurred after the procedure, all in elderly patients or patients at high risk. Five patients (1.4%) needed early conversion (immediate, 2 days) to open repair for access problems or technical difficulties with deployment, resulting in an implantation success rate of 98.6%. Eight patients (2.2%) underwent late conversion for a variety of problems, including AAA expansion (n = 4), endograft thrombosis (n = 1), secondary graft infection (n = 2), and rupture at 3 years (n = 1). Rupture occurred in an additional two patients for a total incidence rate of 0.8%. AAA sac growth of greater than 5 mm was observed in 20 patients (5.6%), four of whom have undergone successful catheter-based treatments to date. Overall, 39 patients (10.7%) needed catheter-based (n = 45) or limited surgical (n = 4) reinterventions for a variety of late problems that were successful in 92%. CONCLUSION: In our 7-year experience, one or more clinical failures of endovascular AAA repair were observed in 31 patients (8.3%). Reinterventions were necessitated in a total of 10.7% of patients but were usually successful in maintaining AAA exclusion and limiting AAA growth. These results emphasize that endovascular repair provides good results and many benefits for most properly selected patients but is not as durable as standard open repair.