Abstract:
A needle catheter with an axially elongating and contracting needle and methods of using for delivering therapeutic materials to the heart are disclosed.

Description:
FIELD OF THE INVENTION 
     The present invention is directed to a needle catheter with an axially elongating and contracting needle. 
     BACKGROUND OF THE INVENTION 
     Needle injection catheters are used for the delivery of cells or other biologic or therapeutic materials into various internal organs including the heart. The needle component spans the length of the catheter and functions as a fluid transport lumen to transport an injectable material from the proximal end of the catheter to the distal end of the catheter where the needle tip acts to inject the material into the target tissue. In order to puncture the tissue, the needle must be extended from the catheter. It must be retracted and sheathed, however, in order to effectively deliver the end of the catheter to the target area. Thus, the use of needle catheters require that the ends of the fluid transport lumen, that is the needle tip and the injection luer fitting at the proximal end of the catheter, must be moved relative to each other. 
     In commonly used needle catheters, a handle shell surrounds a needle, a manifold, a septum and a fluid lumen. The fluid lumen interacts with a luer fitting at the proximal end of the handle where it is can be attached to a syringe containing cells or other biologic or therapeutic materials. The fluid lumen also interacts with the manifold and septum in the middle region of the handle at which point it is coupled to the needle. Once the distal end of a catheter is positioned at a target tissue, the needle is extended by moving the needle relative to the manifold and fluid lumen while a fluid tight seal is maintained by the septum. The needle is retracted by reversing the process. These systems, however, are costly, difficulty to manufacture and prone to leakage. 
     There is a need in the art, therefore, for novel needle catheter assemblies that are easy to manufacture and less prone to leakage. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a needle catheter that includes a hollow handle comprising a proximal end, a distal end and a lumen extending from the proximal end to the distal end, a movable knob disposed on a rod that is attached to the distal end of the handle and a needle comprising a reversibly deformable material positioned within the handle, wherein the proximal end of the needle is operatively coupled to a proximal hub that is positioned in the proximal end of the handle and a medial part of the needle runs centrally through the rod and movable knob such that when the knob is moved the needle moves with it. 
     In various aspects, the reversibly deformable material can be nitinol, stainless steel, cobalt chromium, nylon, urethane, polyurethane, polyvinylchloride or polyester. 
     In various aspects, a fluid lumen is operatively coupled to the proximal end of the needle at the proximal hub which is positioned at the proximal end of the handle. 
     In various aspects, the proximal end of the needle is coupled to the proximal hub by adhesive bonding, thermal welding or press fitting. 
     In various aspects, when the movable knob is positioned adjacent to the distal end of the handle the needle is substantially coiled, bowed or wave-shaped. In various aspects, the shape of the needle is formed by heat treatment. 
     Another aspect of the present invention relates to a method for delivering therapeutic materials into heart tissue that involves providing a needle catheter according to the invention, providing a therapeutic material and administering the therapeutic material into the heart tissue. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A-B  depict the handle section of a needle catheter of the invention.  FIG. 1A  shows the knob in a position adjacent to the distal end of the handle wherein the needle is substantially coiled.  FIG. 1B  shows the knob positioned away from the distal end of the handle wherein the needle is extended. 
         FIG. 2  depicts the handle section of a needle catheter showing the knob in a position adjacent to the distal end of the handle wherein the needle is substantially wave-shaped. 
         FIG. 3  depicts the handle section of a needle catheter showing the knob in a position adjacent with to the distal end of the handle wherein the needle is substantially bowed. 
     
    
    
     DETAILED DESCRIPTION 
     As used herein, the use of the singular includes the plural and visa versa unless expressly stated otherwise. That is, “a” and “the” are to be construed as referring to one or more of whatever the word modifies. 
     As used herein, “catheter” refers to a tube that can be inserted into a body cavity, duct or vessel allowing for the injection of fluids, access to internal organs by surgical instruments, e.g., a needle, or the placement of implantable medical devices, e.g., a stent. A catheter can be a thin, flexible tube, i.e., a soft catheter, or a larger solid tube, i.e., a hard catheter. 
     As used herein, “needle” refers to a hollow tube with a sharp distal end used to inject substances into a tissue. 
     As used herein, “needle catheter” refers to a catheter in which a needle is disposed such that the needle can be delivered to a site within the body in order to inject a therapeutic material into a target tissue. 
     As used herein, “tissue” generally refers to any group of cells that in the aggregate perform the same function and specifically refers to tissues that receive blood through a dedicated arterial system, such tissues including the lungs (pulmonary artery), liver (hepatic artery), kidneys (renal artery) and heart (coronary artery). 
     As used herein, “lumen” refers to a cavity of a tubular structure including an organ such as a blood vessel or a device such as a catheter or catheter handle. 
     As used herein, “reversibly deformable material” refers to any material that can be repeatedly induced to change shape upon the application of a specific stimulus to the material, e.g., pressure or heat, yet upon removal of the stimulus will return to its original shape. It is to be understood that a stimulus appropriate for the present invention includes sliding the knob over the rod, as depicted in  FIGS. 1A and 1B . Examples of reversibly deformable materials suitable for the present invention include, without limitation, nitinol, stainless steel, cobalt chromium, nylon, urethane, polyurethane, polyvinylchloride and polyester. 
     As used herein, “operatively coupled” refers to the attachment of a needle of the invention to either the proximal hub or the fluid lumen of the needle catheter through direct or indirect means, respectively. For example, it is possible for the needle to be coupled to the proximal hub directly, e.g., through adhesive bonding, thermal welding or press fitting. Alternatively, it is possible for the needle to be coupled to the fluid lumen indirectly such that the needle would attach to an intermediate component, e.g., the proximal hub, which in turn would be coupled to the fluid lumen, as depicted in the figures herein. 
     As used herein, “adhesive bonding” refers to a method where two materials, e.g., metals, plastics or composites, are joined using an adhesive, e.g., glue or epoxy. 
     As used herein, “thermal welding” refers to a method where two materials, e.g., metals, plastics or composites, are joined by heating one or both of the materials and fusing the materials together so that upon cooling, the materials are effectively bonded together. 
     As used herein, “press fitting” refers to the attachment of two components by friction. For example, the proximal end of a needle can be compressed so that it fits into a slightly larger component orifice, e.g., a proximal hub, at which point the proximal end of the needle is allowed to return to its normal size, thereby being held tight by the orifice. 
     As used herein, “substantial” or “substantially” refers to a characteristic of the object of the adverb by which it is understood that the object is not a perfect example as such would be immediately envisaged by the reader. Rather, when modified by the word “substantially,” the object of the modifier would be considered close enough to those of ordinary skill in the art to warrant the object designation. 
     As used herein, “substantially coiled” refers to the shape of a needle that resembles a spiral or corkscrew shape. 
     As used herein, “substantially bowed” refers to the shape of a needle that resembles a bow or curved shape. 
     As used herein, “substantially wave-shaped” refers to the shape of a needle that resembles a sinusoidal curve. 
     The present invention relates to a needle catheter that includes a needle made of a reversibly deformable material. The needle is positioned within the catheter such that it can be delivered to a site within a body in a retracted position but upon being positioned at the target tissue is able to be extended to inject cells or any biologic or therapeutic substance into the tissue. 
       FIGS. 1A-B  show a first aspect of the invention.  FIG. 1A  shows a knob and handle section of needle catheter  100  of the invention. Hollow handle  102  includes proximal end  104 , distal end  106  and lumen  108  extending from proximal end  104  to distal end  106 . Movable knob  110  is disposed on rod  112  which is positioned adjacent to distal end  106  of handle  102  such that knob  110  can slide back and forth along rod  112 . Needle  114  is positioned inside of handle  102  and the proximal end of needle  114  is operatively coupled to proximal hub  116  which is positioned in proximal end  104  of handle  102 . At proximal hub  116 , needle  114  is operatively coupled to fluid lumen  118 . 
     When knob  110  is positioned on rod  112  adjacent to distal end  106 , needle  114  will be in a substantially coiled shape, as shown in  FIG. 1A . It is in this position that distal end  120  of catheter  100  can be moved through the vasculature to a target tissue since needle  114  will be in a retracted position. When knob  110  is moved along rod  112  to become positioned away from distal end  106 , needle  114  will straighten, to some extent as depicted in  FIG. 1B , so that the sharp distal end of needle  114  can penetrate a tissue once the catheter is in position. It is to be understood that both before and after knob  110  is moved, fluid, e.g., a therapeutic substance, can flow from fluid lumen  118  through proximal hub  116  and into needle  114 . It has been determined that the coil of the needle does not significantly change the fluid dynamics within the needle. 
     Because needle  114  is made of a reversibly deformable material, when knob  110  is moved back into a position adjacent to distal end  106 , i.e., the position depicted in  FIG. 1A , needle  114  will reform into a substantially coiled shape. It is to be understood that needle  114  can be used any number of times for the delivery of fluids and that after the needle is extended it will return to is original shape. 
       FIG. 2  and  FIG. 3  show alternative embodiments of the invention.  FIG. 2  depicts knob  210  and handle section  202  of needle catheter  200  of the invention in which needle  214  is present in a substantially waved formation.  FIG. 3  depicts another embodiment of the invention in which needle  314  is substantially bowed. It is to be understood, however, that when knob  210  or  310  is moved along rod  212  or  312  away from distal end  206  or  306  needle  214  and  314  will straighten, to some extent as depicted in  FIG. 1B , so that the sharp distal end of the needle can penetrate a tissue once the catheter is in position. When knob  210  and  310  are moved back into a position adjacent to distal end  206  or  306  of the handle, needle  214  and  314  will reform into either a substantially waved or a substantially bowed shape, respectively. It is to be understood that the needle catheter components depicted in  FIGS. 1 ,  2  and  3  are the same, e.g., knob  110  is the same as knob  210  and  310 . Needles  114 ,  214  and  314 , however, are different as depicted in  FIGS. 1A ,  2  and  3 . 
     Another aspect of the present invention relates to a method for delivering therapeutic materials into heart tissue that involves providing a needle catheter according to the invention, providing a therapeutic material and administering the therapeutic material into the heart tissue. 
     The therapeutic material, also referred to herein as a drug or biologic material, can include cells as well as an antiproliferative agent, an anti-inflammatory agent, an antineoplastic, an antimitotic, an antiplatelet, an anticoagulant, an antifibrin, an antithrombin, a cytostatic agent, an antibiotic, an anti-allergic agent, an anti-enzymatic agent, an angiogenic agent, a cyto-protective agent, a cardioprotective agent, a proliferative agent, an ABC A1 agonist, an antioxidant or any combination thereof. 
     It is to be understood that methods of using a needle catheter according to the invention for the administration of therapeutic materials to heart tissue will be easily ascertainable to those skilled in the art from the disclosures herein. 
     While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications can be made without departing from this invention in its broader aspects. Therefore, the appended claims are to encompass within their scope all such changes and modifications as fall within the true spirit and scope of this invention.