In accordance with the present invention, there is provided a catheter for insertion into a vessel of a patient. The catheter has distal and proximal ends and is made from an elongated flexible shaft also having distal and proximal ends. The shaft has a central lumen extending therethrough which is...http://www.google.es/patents/US5797948?utm_source=gb-gplus-sharePatente US5797948 - Centering balloon catheter
