Issue 16

R. Laczkó et alii, Frattura ed Integrità Strutturale, 16 (2011) 28-33; DOI: 10.3221/IGF-ESIS.16.03 30 T HE ELECTRODES AND STENTS EXAMINED ive coronary stents and Corox OTW 75-UP steroid eluting electrodes were examined. The inner diameter of the polymer tube was 5 mm and the maximum diameter of the electrodes was 1.95 mm. Using this method, the experiments were made only with the minimum 3 mm – diameter stents. They were examined with a stereo microscope (Nikon SMZ2T), a scanning electron microscope (Philips XL 30) and a metallograph inspection microscope (Olympus PMG-3 with Olympus digital camera). 4.5/13 mm stent During the process shown in Fig.4, the stent did not slip out or split. This way the vein can be protected against perforation. In Picture a), the stent is placed next to the electrode. In Picture b), the stent is expanded with the balloon filled with turquoise liquid. In Picture c), the balloon is removed and the electrode is fixed by the stent. In Picture d), the electrode is extracted and the stent is deformed slightly. a) b) c) d) Figure 4 : Stereomicroscopic pictures of the procedure: stent is crimpled and electrode is in the tube (a) , balloon expanded stent (b) , fixed electrode (c) , stent after the extraction of the electrode (d) . 4.5/24 mm stent The head of the electrode caught the stent which can cause injuries to the inner surface of the vessels. Fig. 2 demonstrates the damages to the stent after electrode extraction. Figure 5 : Liberté stent creased (left) and fractured (right) parts. F