Effectiveness of Viabahn in the Treatment of Superficial Femoral Artery Occlusive Disease: A Systematic Review and Meta-analysis.

PURPOSE: To evaluate the effectiveness of the Viabahn stent-graft in the treatment of superficial femoral artery (SFA) occlusive disease. METHODS: A systematic review and meta-analysis of published studies was performed to evaluate the efficacy of the Viabahn for SFA lesions. Studies were stratified according to controlled vs uncontrolled design and analyzed using random-effects models. Outcomes are reported as the risk ratio (RR) and 95% confidence interval (CI). Four prospective randomized controlled trials, one retrospective controlled study, and 9 uncontrolled studies were identified. RESULTS: In controlled studies, primary patency with the Viabahn was superior to other interventions at 1 year (RR 0.63, 95% CI 0.49 to 0.82, p<0.001) and ankle-brachial index (ABI) improvement was greater at 6 months (mean difference 0.05, 95% CI 0.01 to 0.09, p=0.01) compared with other interventions. Subgroup analysis demonstrated a lower incidence of stent fracture in lesions with >15-cm stented lengths. In uncontrolled studies, ABI improvement was consistently superior at all measurement points during follow-up. CONCLUSIONS: Current evidence suggests that the Viabahn stent-graft is a safe and effective option for symptomatic SFA lesions. Prospective multicenter randomized controlled trials with long-term follow-up are needed to confirm the sustained efficacy of the Viabahn device.

Intra-operative fenestration of stent grafts: a note of caution based upon preliminary in vitro observations.

Intra-operative fenestrations of stent grafts make more frail and elderly patients amenable to endovascular surgery but require further assessment of the viability of currently used experimental techniques. Four types of polyester fabrics currently employed in stent grafts were exposed in vitro to various protocols of fenestration: cutting, trocaring, and cantering. The resulting fenestrations were examined by gross observation, light microscopy, and scanning electron microscopy. Blunt fenestration by scissors and sharp penetration led to unpredictable apertures, impairment of the integrity of the grafts, and damage to the filaments. The fenestrations were more likely to extend in the woven fabrics, whereas the knitted fabrics were more resistant to fraying. The use of the electric cautery demonstrated the ability to create a fenestration by simultaneously perforating/cutting and edge sealing. Any safe fenestration requires a perforating method that ensures the sealing of the edge of the graft material with a well-controlled diameter. A preoperative fenestration can be tolerated, but there are risks of damage to the stent grafts when reloading the device. More elegant methods of preoperative fenestration, particularly in situ retrograde laser fenestration, are in development and deserve clinical validation.

Treatment of type I endoleak after endovascular repair of infrarenal abdominal aortic aneurysm: success of fibrin glue sac embolization.

PURPOSE: To analyze a single-center experience of fibrin glue sac embolization to eliminate type I endoleaks after endovascular aneurysm repair (EVAR), assessing the feasibility and effectiveness of the technique in long-term follow-up. METHODS: A retrospective study was conducted involving 783 EVAR patients treated between August 2002 and February 2009. Under a standardized protocol, 42 (5.4%) patients (37 men; mean age 73 ± 8 years) underwent intraoperative transcatheter fibrin glue sac embolization to resolve type I endoleak persisting after initial intraoperative maneuvers to close the leak or in necks too short or angulated for cuff placement. Intrasac pressure was measured before and after glue injection. Computed tomographic angiography was performed to assess the outcome after 3, 6, and 12 months and annually thereafter. RESULTS: In this type I endoleak cohort, 16 (38.1%) patients had proximal necks <10 mm long, and 5 (11.9%) patients had proximal neck angulation >60°; 22 additional devices (8 stents, 14 cuffs) had been placed in the initial attempts to resolve the endoleaks. After fibrin glue injection, 41 (97.6%) of the 42 endoleaks were resolved using a mean 15 ± 10 mL of glue. Intrasac pressure decreased significantly in successfully treated cases. The patient who failed embolotherapy was converted to open surgery (2.4%); he died 2 months later from multiorgan failure. Two (4.8%) patients died in the perioperative period from myocardial infarction. One (2.4%) patient developed right lower extremity ischemia unrelated to the fibrin glue treatment. There were no allergic reactions. Over a median follow-up of 39.9 months (range 10-88), 3 (7.1%) patients died (1 aneurysm-related). Cumulative survival was 90.5% at 1 year, 87.0% at 3 years, and 82.6% at 5 years. The mean maximal aneurysm diameter fell from the baseline 59.5 ± 14.7 mm to 49.0 ± 11.6 mm (p<0.001). Of the 4 patients with increased aneurysm diameter during follow-up, 1 was converted, 2 are being observed due to advanced age, and 1 died of renal failure. No recurrent type I endoleak or glue-related complications were observed in follow-up. CONCLUSION: Fibrin glue sac embolization to eliminate type I endoleak after EVAR yielded excellent results in our experience, effectively and durably resolving the leaks. Balloon occlusion of the proximal aorta must be done during glue injection to block proximal flow and facilitate formation of a structured fibrin clot.

Sutureless anastomoses of small and medium sized vessels by medical adhesive.

PURPOSE: Using an animal model we have assessed sutureless anastomoses. METHODS: The two cut ends of the rabbit common carotid artery were sutured by three stitches with a 120 degrees interval circumferentially, then two optional threads were pulled horizontally and 0.1 ml adhesive was smeared on the attached surface of the two ends. The three stitches were removed after completion of anastomosis. The burst pressure of the anastomosis was measured and compared with that of a traditional sutured artery. RESULTS: The glued anastomosis was associated with: a shorter completion time (8.25+/-6.34 min vs. 20.67+/-14.24 min, P<0.01), less bleeding (3.17+/-9.04 ml vs. 11.04+/-16.28 ml, P<0.01), and equivalent patency (93.8 vs. 87.5%, P>0.05). The sutureless anastomosis was associated with less intimal thickening (decreased by 31.4, 24.5, 23.9 and 31.9%, P<0.01 compared with the traditional suture group at 1, 2, 4 and 12 weeks, respectively). CONCLUSION: Glued anastomoses provides an effective, simple and feasible way for anastomosing small or medium caliber vessels. This technique may reduce intimal injury.