title: Membrane-covered stents: a new treatment strategy for saphenous vein graft lesions.
abstract: The restenosis rate after stenting of lesions in aortocoronary venous bypass grafts still has to be considered unsatisfactorily high. We investigated a new stent design characterized by an expandable polytetrafluorethylene (PTFE) membrane in between two layers of struts. Five consecutive male patients (age 70 +/- 6 years) were followed prospectively who presented with at least two de novo lesions in different grafts 13 +/- 3 years after bypass surgery. A total of 11 lesions were treated located in grafts anastomosed to the circumflex (n = 3), to the LAD (n = 7), and to the right coronary artery (n = 1). Within the same procedure, every patient received membrane-covered stents (n = 6) and conventional stents (n = 5) in either of their lesions. All patients underwent successful interventions. The minimal luminal diameter increased from 1.0 +/- 0.5 to 2.9 +/- 0.6 mm in lesions treated by the membrane-covered stents and from 0.8 +/- 0.4 to 2.4 +/- 0.7 mm in the lesions treated by conventional stents. During follow-up, four out of five patients required angioplasty for in-stent restenosis of lesions covered by a conventional stent, whereas no patient underwent revascularization for a lesion treated by a membrane-covered device. The mean minimal luminal diameter of lesions covered by a conventional stent decreased by 42% to 1.4 +/- 0.6 mm; the mean minimal luminal diameter of the lesions treated by a stent graft declined by 9% to 2.8 +/- 0.6 mm (P < 0.05). This series of intraindividual comparisons suggests that membrane-covered stents may have the power to reduce in-stent restenosis in obstructed aortocoronary venous bypass grafts.
authors.affiliation: Department of Cardiology, Kerckhoff Heart Center, Bad Nauheim, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Baldus
authors.forename: R
authors.initials: R
authors.lastname: Köster
authors.forename: J
authors.initials: J
authors.lastname: Reimers
authors.forename: J
authors.initials: J
authors.lastname: Kähler
authors.forename: T
authors.initials: T
authors.lastname: Meinertz
authors.forename: C W
authors.initials: CW
authors.lastname: Hamm
mesh_terms: D000368:Aged; D005500:Follow-Up Studies; D006083:Graft Occlusion, Vascular / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011138:Polytetrafluoroethylene; D012501:Saphenous Vein / Q000601:surgery; D015607:Stents / Q000009:adverse effects
chemical_list: D011138:Polytetrafluoroethylene