A stent having varying outward radial force along its length. In use, the stent can provide greater force in vessel regions requiring greater force and less force in regions requiring less. In particular, more force is provided in the narrowed, center of a stenosis, while not applying too much...http://www.google.es/patents/US5836966?utm_source=gb-gplus-sharePatente US5836966 - Variable expansion force stent
