Catheter systems and packaged kits for dual layer guide tubes
A catheter-based/intravascular ablation (denervation) system includes a multiplicity of needles which expand open around a central axis to engage the wall of a blood vessel, or the wall of the left atrium, allowing the injection of a cytotoxic and/or neurotoxic solution for ablating conducting tissue, or nerve fibers around the ostium of the pulmonary vein, or circumferentially in or just beyond the outer layer of the renal artery. The expandable needle delivery system is formed with self-expanding materials and include structures, near the end portion of the needles, or using separate guide tubes. The system also includes means to limit and/or adjust the depth of penetration of the ablative fluid into the tissue of the wall of the targeted blood vessel. The preferred embodiment of the catheter delivered through the vascular system of a patient includes a multiplicity of expandable guide tubes that engage the wall of a blood vessel. Injection needles having injection egress at or near their sharpened distal end are then advanced through the guide tubes to penetrate the wall of the blood vessel to a prescribed depth. The ability to provide PeriVascular injection so as to only affect the outer layer(s) of a blood vessel without affecting the media has particular application for PeriVascular Renal Denervation (PVRD) of the sympathetic nerves which lie in the adventitia or outside the adventitia of the renal artery.
1. A packaged catheter for injection of fluid into tissue outside of an inner wall of a target vessel of a human patient, the packaged catheter including:
a catheter body having a central axis extending in a longitudinal direction,
at least three needle guiding elements adapted to advance outwardly toward the inner wall of the target vessel,
at least three needles, wherein each needle of the at least three needles is disposed within a respective needle guiding element of the at least three needle guiding elements, the at least three needles adapted to be advanced outwardly relative to the at least three needle guiding elements and guided by the at least three needle guiding elements, the at least three needles each having a distal opening for fluid delivery into the tissue outside of the inner wall of the target vessel,
the catheter being placed in a package with the at least three needle guiding elements deployed in a deployed configuration and each needle of the at least three needles is disposed within the respective needle guiding element of the at least three needle guiding elements, wherein the at least three needle guiding elements are configured to be retracted from the deployed configuration to a retracted configuration relative to the catheter body to be ready to use.
2. The catheter of claim 1 , wherein the at least three needle guiding elements are movable between the retracted configuration and the deployed configuration.
3. The catheter of claim 2 , wherein the at least three needle guiding elements are configured to be constrained within the catheter body in the retracted configuration.
4. The catheter of claim 2 , wherein the at least three needle guiding elements are adapted to extend outwardly from the catheter body in the deployed configuration.
5. The catheter of claim 2 , wherein the deployed configuration allows the at least three needles to extend outwardly from the at least three needle guiding elements for injection of an ablative fluid.
6. The catheter of claim 2 , where the at least three needle guiding elements and the at least three needles are retracted within the catheter body in the retracted configuration for delivery into the human patient.
7. The catheter of claim 2 , wherein a distal portion of the at least three needle guiding elements are in line with a longitudinal axis of the catheter body in the retracted configuration.
8. The catheter of claim 1 , wherein the at least three needle guiding elements comprise plastic.
9. The catheter of claim 1 , further including a radiopaque marker.
10. The catheter of claim 1 , wherein the at least three needle guiding elements include an inner layer and an outer layer.
11. The catheter of claim 10 , wherein the inner layer and the outer layer comprise different plastics.
12. The catheter of claim 1 , further including a handle adapted to move the at least three needles out of the at least three needle guiding elements.
13. The catheter of claim 1 , wherein an injection volume of fluid of the catheter is less than 1 ml.
14. The catheter of claim 13 , wherein the fluid comprises an alcohol.
15. The catheter of claim 1 , further including an external source of fluid for injection into the tissue outside of the inner wall of the target vessel.
16. The catheter of claim 1 , further including a radiopaque marker near a distal end of the at least three needle guiding elements.
17. The catheter of claim 1 , wherein the package is sterile.