Method and apparatus for local delivery of therapeutic agent

A method of delivering a therapeutic substance to tissue within a patient comprising:

• providing an elongate shaft and at least one delivery conduit having a lumen, a proximal end, a distal end, a proximal portion and a distal portion wherein the distal end is attached to the shaft and at least the proximal portion extends substantially parallel to the shaft and is slidable relative to the shaft, the distal end having at least one perfusion port and a proximal end being in fluid communication with a source of a therapeutic substance;
• inserting the shaft and conduit combination into the patient and navigating the combination through the vessels of the patient so that the distal portion of the conduit is adjacent tissue to be treated;
• moving the conduit and shaft relative to one another such that the conduit bows radially outward from the shaft toward the tissue to be treated;
• pressurizing the therapeutic substance through the lumen of the conduit to eject the substance through the perfusion port, outward to the area of tissue to be treated;
• and
• rotating the conduit about a longitudinal axis of the shaft while the conduit is in its bowed, radially outward configuration and the therapeutic substance is being, ejected through the perfusion ports.

A therapeutic substance delivery device comprising:

• an elongate shaft having a proximal end and a distal end and having an inflatable member adjacent the distal end thereof;
• a plurality of expandable delivery conduits, each having a proximal end and a distal end, at least portions of which extend substantially parallel with the shaft and are associated with the shaft such that the conduits are expanded by the relative movement of the shaft and the conduits and the inflatable member is expanded by pressurized fluid;
• and
• a ring slidably mounted on the elongate shaft and joined to the distat end of each conduit.

A method of dilating a vessel and delivering a therapeutic substance to the vessel comprising:

• providing a balloon dilatation catheter having a shaft with proximal and distal ends and a stop at the distal end and at least one conduit having proximal and distal ends and a lumen extending therethrough with a plurality of perfusion ports adjacent its distal end;
• a ring slidable about the shaft and joined to the distal end of the conduit;
• inserting the catheter and conduit into a patient and navigating it to a treatment site within a vessel;
• inflating the balloon of the balloon catheter at the treatment site to dilate the vessel while the ring and conduit are proximal to the balloon;
• deflating the balloon and advancing the ring and conduit distally over the catheter shaft so that the ring is distal to the balloon and the perfusion ports of the conduit are located at the treatment site;
• applying a force on the conduit in a distal direction so that the ring abuts the stop at the distal end of the catheter causing the conduit to bow radially outward toward the vessel wall;
• delivering a therapeutic substance through the lumen of the conduit such that it perfuses through the perfusion ports to the area of the treatment site.

A method of dilating a treatment site within a vessel and delivering a therapeutic substance to the treatment site comprising:

• providing a balloon dilatation catheter having a shaft with proximal and distal ends and a balloon mounted adjacent the distal end and at least one delivery conduit having proximal and distal ends and proximal and distal portions with a plurality of perfusion ports along the distal portion and the proximal end being in fluid communication with a source of a therapeutic substance, the distal end of the conduit is joined to the shaft of the balloon catheter such that relative movement of the conduit and balloon catheter shaft causes at least the distal portion of the conduit to bow radially outward from the catheter shaft;
• inserting the balloon catheter and delivery conduit into a patient and then navigating it so that the balloon is adjacent the treatment site;
• inflating the dilatation balloon to dilate the vessel;
• deflating the balloon after the vessel is dilated and advancing the balloon catheter and conduit distally so that the distal portion of the conduit and perfusion ports are adjacent the treatment site;
• advancing the conduit distally relative to the balloon catheter to cause the distal portion of the conduit to bow radially outward toward the treatment site;
• delivering a therapeutic substance through the conduit so that it perfuses through the perfusion ports.