title: PTFE-covered self-expanding nitinol stents for the treatment of severe iliac and femoral artery stenoses and occlusions: final results from a prospective study.
abstract: OBJECTIVE
  To evaluate the technical performance, safety, and 1-year clinical efficacy of polytetrafluoroethylene (PTFE)-covered nitinol stents in the treatment of atherosclerotic iliac and superficial femoral artery (SFA) disease.
  
  
  METHODS
  The multicenter, prospective, nonrandomized COVENT study involved 98 patients (70 men; mean age 64+/-10 years) who received PTFE-covered nitinol stents in 107 arteries (60 iliac and 47 SFAs) after predilation. The average lesion length was 50 mm in the SFA and 45 mm in the iliac arteries. Postdilation was performed when necessary. Duplex ultrasound and ankle-brachial index (ABI) were performed at discharge and at 1, 6, and 12 months in follow-up.
  
  
  RESULTS
  In total, 130 stents were placed successfully in 97 (99%) of 98 patients. One stent was misplaced during deployment and required subsequent surgical removal. The average stenosis grade was reduced from 98% to 6% in the SFAs and from 96% to 4% in the iliac arteries after covered stent placement. There was a significant rise of the mean ABI from 0.64 at baseline to 0.97 and 0.95 at 1 and 12 months, respectively (p<0.001). There were 7 primary covered stent occlusions (6.5% of 107 stented lesions: 3 not treated, 2 bypassed, 2 dilated or stented) and 5 (4.7%) recurrent in-stent occlusions (1 bypassed, 2 dilated, 2 untreated) during the 1-year follow-up. Primary patency rates were 92% at 6 months and 89.8% at 12 months for the entire cohort. Secondary patency rates were 98% and 95.6%, respectively. No statistically significant differences were observed in the primary patency rates for the SFAs (89.3% at both 6 and 12 months) versus the iliac arteries (94.3% at 6 months and 90.7% at 12 months).
  
  
  CONCLUSIONS
  Primary implantation of PTFE-covered nitinol stents in the iliac and superficial femoral arteries is technically feasible, safe, and effective, with excellent 1-year patency.
authors.affiliation: Division of Diagnostic Radiology, Department of Radiology, University of Tübingen, Germany. benjamin.wiesinger@med.uni-tuebingen.de
authors.forename: Benjamin
authors.initials: B
authors.lastname: Wiesinger
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Beregi
authors.forename: Vincent L
authors.initials: VL
authors.lastname: Oliva
authors.forename: Tobias
authors.initials: T
authors.lastname: Dietrich
authors.forename: Gunnar
authors.initials: G
authors.lastname: Tepe
authors.forename: Marc
authors.initials: M
authors.lastname: Bosiers
authors.forename: Kayman
authors.initials: K
authors.lastname: Hüttl
authors.forename: Stefan
authors.initials: S
authors.lastname: Müller-Hülsbeck
authors.forename: Alan
authors.initials: A
authors.lastname: Bray
authors.forename: Hans
authors.initials: H
authors.lastname: Tielemans
authors.forename: Stephan H
authors.initials: SH
authors.lastname: Duda
mesh_terms: D000368:Aged; D000497:Alloys; D000800:Angioplasty, Balloon; D001157:Arterial Occlusive Diseases / Q000628:therapy*; D005240:Feasibility Studies; D005260:Female; D005263:Femoral Artery; D005500:Follow-Up Studies; D006801:Humans; D007083:Iliac Artery; D008297:Male; D008875:Middle Aged; D011138:Polytetrafluoroethylene; D011446:Prospective Studies; D012720:Severity of Illness Index; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome; D014654:Vascular Patency
chemical_list: D000497:Alloys; C013616:nitinol; D011138:Polytetrafluoroethylene