Long-Term Follow-Up of Endovascular Repair in the Management of Arterial Stenosis Caused by Takayasu's Arteritis.

BACKGROUND: This retrospective study evaluated the long-term results of endovascular repair in the management of arterial stenosis caused by Takayasu's arteritis (TA). METHODS: Sixty-seven endovascular procedures (percutaneous transluminal balloon angioplasty or stenting) were performed for 49 arterial lesions in 35 patients. Endovascular treatment was performed when the disease was inactive. The patients were pretreated with immunosuppressive drugs and were followed every 3-6 months to monitor disease activity and medical treatment. Doppler ultrasonography and magnetic resonance angiography were performed every 6 months. Kaplan-Meier method with the log-rank test was used to analyze the survival of renal artery procedures because the number of lesions in other territories was not sufficient for statistical analysis. The mean follow-up duration after the endovascular procedure was 83 months (range: 12-144 months). RESULTS: Twenty-two (33%) endovascular interventions resulted in restenosis or occlusion. Reinterventions resulted in primary assisted patency in 45 (92%) lesions with restenosis. Only 4 (8%) of the 49 arterial lesions were occluded at the time of the final evaluation. The overall patency rate for the renal artery stents was 93.7% (15/16) after 8 years of follow-up. In the Kaplan-Meier survival analyses of the renal artery lesions, the 1- and 8-year restenosis-free survival rates of renal arterial interventions were 74% and 57%, respectively, (P = 0.281). CONCLUSIONS: In this study, endovascular treatment with adequate immunosuppressive medication resulted in long-term patency with one- or multi-stage reinterventions in 92% of stenotic arterial lesions caused by TA.

Endovascular Treatment of Thrombosis and Embolism.

Deep venous thrombosis (DVT) is a common disorder with a significant mortality rate. Successful endovascular treatment of acute DVT is most likely to be achieved in patients with recently formed thrombus, (<10-14 days) with acute iliofemoral DVT. Endovascular treatment options include: Catheter-directed thrombolysis (CDT), pharmacomechanical catheter-directed thrombolysis (PCDT), percutaneous aspiration thrombectomy (PAT), vena cava filter protection, venous balloon dilatation and venous stent implantation. Current practice shows strong clinical tendency for the use of PCDT with or without other endovascular methods and an individualized approach for each DVT patient. PMT has not received general acceptance because of the associated risk of PE and damage to venous valves caused by thrombectomy devices. PAT is most commonly used as an adjunctive endovascular technique like balloon maceration to fragment thrombus, balloon angioplasty, stent implantation and vena cava filter placement. Interventional endovascular therapies for DVT have the potential to provide PE protection and prevention of PTS. Patient centered individualized approach for endovascular DVT treatment is recommended to optimize the ideal clinical result.Acute stroke is the leading cause of death for people above the age of 60 and the fifth leading cause in people aged 15-59. Mortality during the first 30 days of ischemic stroke is 20 % and 30 % of survivors will remain permanently disabled. Acute stroke patients within the therapeutic window must receive IVrtPA unless there is a contraindication. In case of contraindication to IVrtPA or for patients out of the therapeutic window for thrombolytics, standart of care is the intraarterial treatment. Patients have to be transferred to a comprehensive stroke center with capacity of dedicated neurovascular imaging and interventional neuroradiology. Noncontrast head CT that is used to rule out hemorrhage is followed by imaging studies dedicated to show if there is reasonable penumbra to save. Intraarterial thrombolysis has the main advantage of extended therapy window, earlier and more efficient recanalization and less risk of hemorrhage due to lower doses of thrombolytics. Mechanical thrombectomy has several advantages over IV/IA fibrinolysis including faster recanalization and less risk of hemorrhage especially in large artery occlusions. ASA guidelines recommend choosing stent retrievers over other devices for mechanical thrombectomy. Better recanalization rates and less infarct volume after mechanical thrombectomy result in higher numbers of functionally independent patients compared with other treatments. Two landmark studies that were published recently, SWIFT PRIME and MR CLEAN, showed that IA treatment especially with the new stent retrievers lead to a significant increase in functional recovery and independence in daily life after an acute stroke.Cerebral venous and sinus thrombosis (CVST) comprises nearly 0.5-1 % of all stroke cases. CVST causes different neurological deficits depending on the sinus/cortical vein involved. CVST may cause death and dependency in 13.4 % of patients. CT/CT venography and MR/MR venography can be effectively used to diagnose and to follow up CVT cases. Anticoagulation with heparin is the most widely accepted therapy to prevent the expansion of the thrombus. Patients deteriorating despite heparinization and patients presenting with very severe neurological deficits must receive endovascular treatment. Endovascular methods include intrasinus infusion of thrombolytics or heparin, balloon angioplasty, mechanical thrombectomy or a combination of different techniques. There is a higher rate or recanalization with endovascular methods compared to other medical therapies.

An Aortoenteric Fistula Arising after Endovascular Management of a Mycotic Abdominal Aortic Aneurysm Complicated with a Psoas Abscess.

Mycotic aortic aneurysms account for 1-3% of all aortic aneurysms. The management of this disease is controversial. Since open surgical repair is associated with high morbidity and mortality rates, endovascular aneurysm repair is an alternative treatment method with promising early and midterm outcomes, although its long-term durability is unknown. Secondary aortoenteric fistulas may occur iatrogenically after either aortic reconstructive surgery or endovascular repair. As the number of aneurysms managed with endovascular aneurysm repair has substantially increased, cases of aortoenteric fistulas referred for endovascular repair are augmented. We report the case of an aortoduodenal fistula manifested with duodenal perforation after staged endovascular and surgical treatment of a mycotic aortic aneurysm.

Endovascular Stent-Graft Treatment of Giant Celiac Artery Pseudoaneurysm.

BACKGROUND: Visceral artery aneurysms (VAAs) comprise an uncommon but life-threatening vascular disease. When rupture is the first clinical presentation, mortality rate reaches 70%. Increased use of cross-sectional imaging has led to a greater rate of diagnosis (40-80%) of asymptomatic VAAs. In the past, surgery was the treatment of choice for VAAs carrying high risk of mortality and morbidity. CASE REPORT: A 22-year-old man, who had undergone gastric, pancreatic and aortic surgery 2.5 years earlier, presented with progressive abdominal pain. Multidetector computed tomography scan revealed an 8-cm celiac pseudoaneurysm. We report a giant celiac pseudoaneurysm treated with stent-graft implantation. CONCLUSIONS: Endovascular treatment of VAA is a safe and effective method alternative to surgery.

Automated measurement of intima-media thickness of carotid arteries in ultrasonography by computer software.

PURPOSE: Intima-media thickness (IMT) has been proposed to be a morphological criterion of atherosclerosis. The purpose of this study was to investigate the interobserver variability of manual and also of computer software measurements of IMT. MATERIALS AND METHODS: High-resolution common carotid artery (CCA) images of 88 patients that have been obtained by a linear broadband L5-12 MHz transducer and archived in PACS were retrospectively evaluated. Two separate investigators, who were unaware of the former results, evaluated the same images by using computer software that had a dedicated tool for automatic measurement of IMT. The results of the investigators were compared. RESULTS: According to the two investigators who have performed manual measurements, mean values of IMT of right CCA were 0.6396 mm and 0.6356 mm; of the left CCA were 0.6662 mm and 0.6575 mm, respectively. The interobserver variability of measurements revealed the mean IMT as 0.6071 mm and 0.6048 mm for the right, 0.6216 mm and 0.6227 mm for the left CCA. Manual measurements of both investigators were found to be higher than the automatic measurements and the differences were statistically significant. Interobserver correlation of manual measurements was between 0.80-0.88 and of the automated measurements was between 0.93-0.98. CONCLUSION: Manual measurements reveal higher values than the automated measurements of IMT. The interobserver correlation of automated measurements is higher than manual measurements. The use of dedicated software may be proposed to reduce the measurement errors.

Comparison of the endothelialization of small intestinal submucosa, dacron, and expanded polytetrafluoroethylene suspended in the thoracoabdominal aorta in sheep.

PURPOSE: This study was undertaken to evaluate and compare endothelialization of small intestinal submucosa (SIS), Dacron, and expanded polytetrafluoroethylene (ePTFE) in high-pressure flow without aortic wall contact and to evaluate the suitability of SIS as a vascular graft material. MATERIALS AND METHODS: In 12 adult sheep, three types of membrane leaflets of similar thickness (approximately 200 mum) were suspended within large square stents without contact with the thoracoabdominal aortic wall: SIS (n = 12), Dacron (n = 12), and ePTFE (n = 12). Each animal received one leaflet of each material. Aortograms were obtained before and after percutaneous implantation and when the animal was killed at 8 weeks (n = 6) or 18 weeks (n = 6). Cell coverage and remodeling of SIS, Dacron, and ePTFE membranes were assessed by gross and histologic microscopic examinations. RESULTS: Thirty-five successfully implanted leaflets were evaluated. SIS showed progressive remodeling. Thirty-three leaflets exhibited thickening as a result of neointimal formation and endothelialization, most likely from circulating endothelial cells. Dacron exhibited the greatest and most progressing degree of neointimal formation and endothelialization, followed by SIS and then ePTFE. With SIS and ePTFE, neointimal formation decreased with time, but endothelialization was stable. Uneven neointimal formation and endothelialization on the outer surfaces and distal leaflet positions were seen. CONCLUSIONS: SIS showed progressive remodeling with moderate and regressive neointimal formation and moderate stable endothelialization. Further study of its durability and incorporation into the aortic wall needs to be performed to evaluate its suitability as a cover for aortic endografts.

Percutaneous treatment of hydatid liver cysts in children as a primary treatment: long-term results.

PURPOSE: To evaluate the effectiveness and long-term results of percutaneous treatment for hydatid liver cysts in pediatric patients. MATERIALS AND METHODS: Thirty-four pediatric patients (15 male, 19 female; ages 4-17 years; mean age, 9.4 years) with 51 hydatid liver cysts underwent ultrasound (US)-guided percutaneous treatment with albendazole prophylaxis. There were 15 type II lesions with membrane detachment and 36 type I lesions resembling simple hepatic cysts with pure anechogenic content or small echogenic reflections and a regular well-delineated wall. The method of US-guided puncture, aspiration, injection of hypertonic saline solution, and reaspiration was preferred for 21 lesions. For the remaining 30 larger cysts, the intervention was performed with the same percutaneous technique but followed by catheterization, drainage, control cystography, and sclerotherapy with ethanol. During follow-up, US examinations were performed at 1, 3, 6, and 12 months for the first year and yearly thereafter. RESULTS: Percutaneous treatment of hepatic hydatid disease was successful in 33 patients (97.1%). During follow-up, US findings in the lesions changed significantly; at year 1, the inner content of the lesions became heterogeneous with a semisolid appearance, and the mean reduction in volume was 81.4%. At 2-year follow-up, most hydatid cysts had become solid in nature and the reduction in volume reached 65%-99% (mean, 85.1%). There were no recurrences or additional lesions after the follow-up of 1-6 years (mean, 3.1 years). Average hospital stay for the whole group in this study was 3.5 days. CONCLUSIONS: The long-term results of percutaneous liver hydatid cyst treatment in children are in accordance with the results in adults. Percutaneous treatment of uncomplicated type I and type II liver hydatid cysts in pediatric patients is an efficient and safe treatment with short hospitalization.

Long-term optional retrievability of a new inferior vena cava filter in an ovine model.

Long-term retrievability of a new optional retrieval inferior vena cava (IVC) filter composed of a modified square stent and a modified Günther Tulip filter was tested in eight sheep. Eleven filters were placed into the IVC and eight were successfully retrieved 3-5 months after implantation. Incorporation of the filter struts into the IVC wall prevented its retrieval in three sheep at 3, 4, and 5 months after placement.

Significance of spatial orientation of percutaneously placed bioprosthetic venous valves in an ovine model.

PURPOSE: To investigate two spatial orientations of a percutaneously placed bicuspid second-generation bioprosthetic venous valve (SG-BVV) in the jugular vein (JV). MATERIALS AND METHODS: Twelve SG-BVVs, consisting of small intestinal submucosa attached to a nitinol frame were placed across a natural valve (NV) in the distal JV in six sheep. Six SG-BVVs were oriented as NV leaflets (group A) and the other six SG-BVVs were rotated 90 degrees to NV leaflets (group B). SG-BVV function was studied by venography performed immediately after placement and at 5 weeks after placement. Animals were killed at 5 weeks, and gross examinations were performed. RESULTS: Desired valve orientation after deployment was seen in all SG-BVVs. In group A, all valves exhibited good valve function on immediate and 5-week venography. At gross examination, leaflets were attached mostly at the valve base and free cusp areas were similar in both cusps with a mean of 154.8 mm2 +/- 45.6 for one cusp and 142 mm2 +/- 53.4 for the other cusp (P = .188). In group B, all valves showed good function on immediate venography and in five valves prior to killing. Valve attachment to the vein wall in this group involved a longer segment of leaflets and their free areas were smaller with a wide variety of cusp sizes. Mean free leaflet areas of opposing cusps measured 106.3 mm2 +/- 36.5 and 66.1 mm2 +/- 34.6, respectively (P = .025). Difference in leaflet areas between group A and group B was significant (P = .019). CONCLUSION: Proper spatial orientation of the SG-BVV at deployment is important for valve function and should have the same orientation as the NV.