Catheters having rapid-exchange and over-the-wire operating modes

An intravascular catheter capable of both rapid-exchange and over-the-wire modes of operation having a relatively long proximal shaft portion, a relatively short distal section and an intermediate shaft section, which connects the proximal shaft section and the distal shaft section. In one embodiment, the intermediate shaft section includes a guide wire port and a first guide wire lumen which extends throughout both the intermediate and distal shaft section, and a second guide wire lumen which extends throughout the entire catheter shaft. In another embodiment, the intermediate shaft section includes a y-lumen junction which allows a first guide wire lumen introduced at the intermediate shaft section and a second guide wire lumen extending from the proximal end of the catheter shaft throughout the proximal shaft section to merge and communicate with a single distal guide wire lumen which extends from the intermediate shaft section to the distal end of the catheter shaft. In another embodiment, the catheter shaft includes a single guide wire lumen extending from the proximal end to the distal end wherein the guide wire lumen is defined by a proximal section and a distal section. The proximal section guide wire lumen includes a slit which allows a guide wire to be removed for rapid-exchange mode of operation or retained for over-the-wire mode of operation.