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Time changes in plasma concentrations of six different cytokines were investigated to evaluate the inflammatory response to renal artery stent placement.A total of 22 patients (17 men; mean age, 66 years +/- 13) with ostial renal artery stenosis and poorly controlled hypertension treated with stent placement were studied. Blood samples were collected at baseline and at 24 hours and 6 months after the intervention. Plasma concentrations of (i) tumor necrosis factor-alpha, (ii) interleukin-6 (IL-6), (iii) monocyte chemoattractant protein-1, (iv) intercellular adhesion molecule-1, (v) vascular cell adhesion molecule-1, and (vi) regulated upon activatin normal T-cell expressed presumed secreted were measured. Restenosis diagnosed with imaging follow-up at 6 months was recorded. Plasma concentrations of the aforementioned cytokines were compared between patients with and without restenosis.IL-6 concentration increased significantly 24 hours after stent placement (8.3 pg/mL +/- 1.24 vs. 2.76 pg/mL +/- 1.27 at baseline) and returned to baseline levels (2.6 pg/mL +/- 1.77) at 6-month follow-up (P.0001). No significant changes occurred in the concentrations of any other cytokines at the three time points. Baseline and 6-month concentrations of IL-6 were significantly higher in patients with restenosis than in those without restenosis (8.13 pg/mL +/- 4 vs 0.75 pg/mL +/- 0.47 [P.005] and 9.55 pg/mL +/- 6.5 vs 0.42 pg/mL +/- 0.35 [P.02], respectively).Renal artery angioplasty with stent placement induces an inflammatory response, as evidenced by increased IL-6 production. Additionally, IL-6 seems to identify patients prone to develop restenosis; therefore, it might be used as an early predictor of restenosis after renal angioplasty with stent placement. However, larger studies are required to confirm IL-6 as a potential predictor of restenosis.

Dheeraj K. Rajan, MD, FRCPC, Nilesh H. Patel, MD, Karim Valji, MD, John F. Cardella, MD, Curtis Bakal, MD, Daniel Brown, MD, Elias Brountzos, MD, Timothy W.I. Clark, MD, Clement Grassi, MD, MSc, Steven Meranze, MD, Donald Miller, MD, Calvin Neithamer, MD, Kenneth Rholl, MD, Anne Roberts, MD, Marc Schwartzberg, MD, Timothy Swan, MD, Patricia Thorpe, MD, Richard Towbin, MD, and David Sacks, MD, for the CIRSE and SIR Standards of Practice Committees

To investigate the origin of host cells during remodeling of small intestinal submucosa (SIS) square stent-based bicuspid venous valves (VVs).Suspended VVs (SVVs) were developed by suspending VVs within bare square stents so the valve elements would not contact the vein wall after deployment. Eight SVVs were placed within the intrahepatic and infrahepatic inferior venae cavae (IVCs) of four adult female sheep. Eight standard VVs were implanted in the external jugular veins of these animals for comparison. At 5 weeks after placement, the devices were examined for stability and patency and the animals were killed. Gross, histologic, and scanning electron microscopic (SEM) examinations were performed.Follow-up spot radiographs and venography showed no migration of the devices, venous occlusion, or thrombus formation. All SVVs were intact without contact with the IVC wall. Six VVs were competent and two were slightly tilted with some reflux. Histologic study showed remodeling of SVVs and VVs with newly formed collagen fibers; fibroblasts and inflammatory cells were found penetrating the SIS leaflets and endothelial cells on the surface. SIS neovascularization was also present. There was no difference regarding SIS remodeling between SVVs and the free part of VV leaflets. The VV leaflets' bases were thicker compared to their free parts (P.01). SEM examination showed endothelial cells on both sides of the SVVs and VVs. Endothelialization of the SVV central leaflet surfaces and both surfaces of the VV leaflets was more complete than that of the peripheral surfaces of the SVV leaflets.SIS-based valve remodeling occurs independently of vessel wall contact by recruitment of cells directly from the circulation.

PURPOSE To evaluate the efficacy and safety of alteplase, a recombinant tissue plasminogen activator, in hemodialysis access graft thrombolysis. MATERIALS AND METHODS From November 1999 to May 2001, 68 episodes of occlusion in 50 grafts (in 49 patients) were included in the study. Occlusion was treated with pulse-spray ( n = 41) or lyse-and-wait ( n = 27) thrombolysis with use of alteplase. Balloon angioplasty of all identified stenoses was performed. The arterial plug was mobilized with the Fogarty maneuver. RESULTS Procedural success was achieved in 64 of 68 episodes (94%) with a dose of 2–10 mg (mean = 4.13 mg) of alteplase, allowing successful hemodialysis within 24 hours. Failures (6%) were the result of PTA perforation (one of 68), nonnegotiable outflow occlusion (one of 68), delayed bleeding (one of 68), and balloon bursting and shearing becoming occlusive within the graft (one of 68). Primary and secondary patency rates were 72% and 87% at 30 days, 57% and 80% at 90 days, and 44% and 72% at 180 days, respectively. Arterial emboli (two of 68) were treated by Fogarty balloon retrieval and alteplase infusion locally over the course of 20 minutes. One of two PTA perforations was controlled by balloon tamponade. CONCLUSION Alteplase can be used successfully for hemodialysis graft thrombolysis.

JVIR 2000; 11:1179–1183 STENT-GRAFTS are gaining widespread acceptance in the endovascular treatment of aneurysms, pseudoaneurysms, and arteriovenous fistulas because of the less invasive nature of their use compared to standard surgical procedures (1). Fully supported stent-grafts are used in the treatment of thoracic aortic aneurysms (1), abdominal aortic aneurysms (2), iliac artery aneurysms (3–6), superficial femoral artery (SFA) and popliteal artery pseudoaneurysms (7–10), and subclavian artery aneurysms and fistulas (11). Vascular lesions near mobile skeletal joints (ie, hip joint), although potentially treatable with fully supported stents or stent-grafts, are still managed with surgery (12) because of the perceived risk of stent failure or vascular injury caused by motion. To our knowledge, there have been no reports of a fully supported stent-graft placement across the hip joint for the treatment of aneurysmal lesions in humans. We describe our experience of endovascular management of a patient presenting with a common femoral artery (CFA) anastomotic pseudoaneurysm, treated with placement of fully supported stentgrafts. This patient also had a common iliac artery anastomotic pseudoaneurysm that was likewise treated with placement of fully supported stent-grafts.