Agent delivery catheters
AssigneeAbbott Cardiovascular Systems Inc.
InventorWilliam E. Webler
Life of this patent
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Abstract
An agent delivery catheter that includes an anti-whipping feature, improved assembly of distal parts and/or accuracy/repeatability of needle delivery to a target tissue. Additional features include fitting a catheter with a pneumatic delivery device for delivery of a therapeutic agent without using a needle.
Claims19
A catheter configured for controlled whipping in rotational increments, wherein a portion of the catheter is forced to assume a curved shape in a patient's vasculature to position a distal portion in an operative position for performing a medical procedure, comprising:
- an elongated tubular shaft having proximal and distal shaft portions, and a lumen therein, the proximal shaft portion configured for transmitting a torque from the proximal shaft portion to the distal shaft portion;
- a first section of the proximal shaft portion having a first flexural modulus;
- and
- a second section of the proximal shaft portion having circumferentially spaced voids, each of which extending lengthwise over the second section;
- wherein the second section is such that the flexural modulus of the second section would be substantially higher than the first flexural modulus if the voids were not formed in the second section;
- and
- wherein the second section occupies a position along the proximal shaft portion that substantially assumes the curved shape.
An agent delivery catheter configured to improve needle accuracy and repeatability when the catheter assumes a curved shape, comprising:
- an elongate shaft including a proximal end and a distal end;
- a tendon disposed within a shaft lumen of the elongate shaft, affixed to the distal end, and offset from a neutral axis of the distal end to enable deflection of a distal tip of the elongate shaft by pulling the tendon towards the proximal end;
- and
- a needle shaft disposed within the shaft lumen and located approximately coincident with the neutral axis.
An agent delivery catheter configured to improve needle accuracy and repeatability when the catheter assumes a curved shape, comprising:
- an elongate shaft including a proximal end and a distal end, the shaft being pre-disposed to deflect in a first direction so that a first region of the elongate shaft is placed in tension and a second region of the elongate shaft is placed in compression;
- a tendon disposed within the shaft lumen and affixed to the distal end, the tendon being offset from a neutral axis to enable deflection of a distal tip of the elongate shaft by pulling the tendon towards the proximal end, whereby the pulling on the tendon compresses the catheter;
- and
- a needle disposed within the shaft lumen, the needle being located in the portion of the first region that negates the compression induced by the tendon.
A method for improving the needle accuracy and repeatability for an agent delivery catheter, comprising the steps of :
- providing a catheter including a shaft having a distal and a proximal end, a tendon assembly disposed within the shaft and configured to deflect the distal tip when the tendon is loaded by an operator at the proximal end, whereby the deflected state of the shaft creates a compressive strain region and a tensile strain region, and the loaded tendon produces a net axial compression on the shaft;
- and
- placing a needle assembly in a tensile strain region caused by the deflection such that the elongation caused by the deflection negates the net compression caused by the loaded tendon,
- wherein the needle assembly includes a needle sheath and a needle within the needle sheath, and the needle sheath is capable of changing length when subjected to compression and tension, and the placing a needle assembly in a tensile strain region caused by the deflection includes placing the needle assembly in a portion of the tensile strain region at which there is a zero net length change of the needle sheath when the shaft is in the deflected state.
Dependencies are inferred from the claim text.