Literature hints at consequent stent expansion after implantation of Wallstents in carotid artery stent angioplasty (CAS) [1]. We wanted to see if this is also the case in our patients.Self-expandable stents used for CAS show a foreshortening. Nitinol stents used during CAS shorten less than 15% of the initial length. However, foreshortening of 20% or more can be seen in Wallstents. Stainless steel stents show less flexibility than nitinol stents.Stainless steel stents are manufactured out of a single wire mesh and have a high radial...

We evaluated 150 patients with ultrasound controls directly after CAS and 6 months later. Additionally we examined of 35 patients 1 year after CAS, 10 patients 2 years after CAS and 5 patients 3 years after CAS.Ultrasound ExaminationWe evaluated the kind of stent implanted, the stent length and the stent diameter in the proximal, middle and distal part of the stent. Ultrasound scans were performed with a Siemens Sonoline Elegra® System. Usually we use a 7.5 MHz linear array transducer, alternatively a 5.0 MHz linear...

Visibility of the stentsIn all cases wallstents show a higher contrast and visibility than nitinol stents in ultrasound controls.Stent measurements one day after CASMean diameters are 6.5mm proximal, 4.4mm in the middle of the stent and at the end. The diameters of stents implanted by us are initially significantly wider than reported in literature.Minimum diameterMaximum diameterMean diameterMedian diameterStandard deviationliterature results [¹]proximal 3.610.36.56.81.25.8 +/- 0.98middle2.26.54.44.30.83.51 +/- 0.76distal3.07.04.44.50.73.67 +/- 0.55Stent diameter one day after CASStent measurements 6 months after CAS6 months after CAS there is no further...

There is no further stent expansion to expect after standardized CAS with pre- and postprocedural dilatation. Balloon diameters of postprocedural dilatation should correspond to the diameter of the healthy distal ICA. In contrast to the results of Willfort-Ehringer we see no relevant dilatation of the stent. This is possible the result of the predilatation of the stenosis before stent implantation.

[1] Willfort-Ehringer A, Ahmadi R, Gruber D et al. (2004):Arterial remodeling and hemodynamics in carotid stents: a prospective duplex ultrasound study over 2 years.J Vasc Surg; 39: 728-734[2] Peeters P, Bosiers M, Verbst J et al. (2004):Self-expanding stents: What makes each available product different?Abstract ICCA 2004

Christel Vockelmann, MD,Assistant medical director, Evangelisches Krankenhaus Mülheim a.d. Ruhr, GermanyMail: [email protected] Demirel, MD,Clinic of Radiology Brüderweg, Dortmund Germany;Katharina Matyssek, MD,Resident, Klinikum Dortmund, Germany;Klaus Mathias, MD,Medical director, Klinikum Dortmund, Germany;