Abstract: An ultrasound catheter adapted for accessing small vessels in the distal anatomy is disclosed. The ultrasound catheter comprises an elongate tubular body formed with a delivery lumen. The flexibility and dimensions of the tubular body allow access to the distal anatomy by advancement over the guidewire. An ultrasound radiating member is provided along the distal end portion of the tubular body for emitting ultrasound energy at a treatment site. A drug solution may also be delivered through the delivery lumen and out an exit port to the treatment site.

Abstract: An ablation burr has a body provided with an inner circumferential rim and an outer circumferential rim that are concentric and spaced longitudinally by a selected distance along the length of the burr. The outer circumferential rim has a generally smooth convex outer surface that reduces damage to a vessel wall or stent. A leading surface of the burr extends between the inner and outer circumferential rims in a substantially uniform, concave manner. An abrasive, for example, diamond grit, is provided on the leading surface. The burr is selectively rotated by a drive shaft, causing the abrasive leading surface of the burr to ablate unwanted deposits. If desired, a wire extends co-axially through the body such that a distal end of the wire extends out of the distal end of the burr. An abrasive tip may be coupled to the distal end of the wire, and is selectively rotated, to ablate unwanted deposits.

Abstract: A catheter for delivering a medical agent to tissue external to a body passage through which the catheter is inserted. The catheter includes a tissue piercing member, e.g., a needle having a rectangular cross-section that is asymmetrically flexible, such that the member is substantially more flexible about a first cross-sectional axis than about a second cross-sectional axis. The tissue piercing member is thus readily deflected about one axis, away from the catheter and into the tissue, while minimizing buckling of the tissue piercing member about the other axis. The catheter can include a balloon located proximal to and on the same side as the piercing member, and a second balloon located distal to and on the opposite side as the piercing member. When inflated, the balloons cause the portion of the catheter between the balloons to flex and bend, facilitating penetration of the tissue by the tissue piercing member.