Abstract: A catheter for use in a body vessel includes a relatively stiff proximal shaft that is shaped as a tube formed with a lumen and having a proximal end and a distal end. Further, the catheter includes a relatively flexible distal tube formed with a lumen and having a proximal end and a distal end. An inflatable balloon may be attached to the outer wall of the distal tube near the distal end. The proximal end of the distal tube is attached to the distal end of the proximal shaft at a transitional joint. The transitional joint provides a gradual transition in flexibility over the length of the joint between the stiff proximal shaft and the flexible distal tube. Importantly, the transitional joint includes an extension made of a material having superelastic properties when positioned inside the body vessel. One end of the extension is attached to the distal end of the proximal shaft. The other end of the extension projects into the lumen of the distal tube.

Abstract: A method and device for injecting fluid into a treatment area of a vessel wall is provided herein. A first version of the device includes an inflatable balloon mounted on a catheter and a plurality of injectors extending outwardly and moving with the balloon. At least one fluid passageway connects each injector in fluid communication with a fluid source. During use of the device, the balloon is first positioned in a vessel proximate the treatment area. Next, the balloon is inflated to embed the injectors into the vessel wall. Subsequently, the fluid from the fluid source is introduced into the fluid passageway and through the injectors into the treatment area. A second version of the device includes a plurality of flexible tubes mounted between a multi-lumen catheter and a grommet. A push-pull wire is connected to the grommet and passed through a lumen of the multi-lumen catheter. The injectors are mounted on each of the flexible tubes. During use, the device is first positioned in a vessel.

Abstract: An over-the-wire atherectomy cutter includes a hollow cylindrical sleeve which is coaxially attached at its proximal end to a hollow rotatable catheter. The periphery of the distal end of the sleeve is sharpened.A hollow, substantially cylindrical body is coaxially positioned within the sleeve in an interference fit. A frustum-shaped portion is formed on the distal end of the body and tapers inwardly toward a hollow cylindrical distal tip. The frustum-shaped portion has two openings which extend the axial length of the frustum-shaped portion, to create a pair of straight blades that connect the body to the tip. The straight blades are contiguous to the sharpened distal end of the sleeve to establish a pair of diametrically opposed arcuate cutting edges that are positioned on the distal end of sleeve.