NEWER STENTS - MATERIALS AND DESIGNS

We aim to present here the experience with newer stents for coronary a nd peripheral interventions. Specifically, the design and technical co nsiderations of the self-expanding nitinol coil stents for coronary an d vascular indications, as well as the design and clinical experience with the tubular stainless steel balloon-expandable serpentine stents for coronary and peripheral interventions are discussed. The animal an d clinical experience with both types of stent have shown that the mec hanisms of deployment and expansion are different for these inherently different stents. The self-expanding coil stent, providing adequate s caffolding in various types of coronary lesions is deployed by self ex pansion, aided to a significant extent by balloon expansion. Long-term outside pressure on the wall may lead to further stent expansion as h as been shown with this stent, which may be an important parameter in the restenosis process. The tubular balloon-expandable serpentine sten t does not have the feature of long-term expansion, however, is charac terized by superior scaffolding properties and unique features that al low its safe use in the most complex coronary diseases. Long-term clin ical results are pending for these two families of stents.