Retroperfusion catheter comprising a flexible elongate element having proximal and distal extremities and having at least first and second lumens extending therethrough. A flexible tip is secured to the distal extremity of the flexible elongate element. A balloon having proximal and distal portions is...http://www.google.es/patents/US4917667?utm_source=gb-gplus-sharePatente US4917667 - Retroperfusion balloon catheter and method
