Catheter positioning systems

Abstract

The present invention provides a catheter positioning system which serves to control and stabilize a distal end of a catheter at a treatment site within a patient so that a medical procedure can be performed with accuracy. Generally, the positioning system operates by providing a deformable mechanical members at the distal end of the catheter which can be operated from the proximal end of the catheter to extend radially outward to engage surrounding tissue adjacent to treatment site. In one embodiment of the invention a flexible superstructure comprising the plurality of flexible veins extending longitudinally along the distal end of the catheter can be deformed to bow radially outward to engage surrounding tissue. The distal tip of the catheter joined to one of the veins was correspondingly displaced or rotated angularly as the veins bow outward. In another embodiment radially projecting fingers are joined to the distal end of the catheter, which remain retracted during navigation of the catheter to the treatment site then are extended outward to penetrate the tissue and secure the catheter at the treatment site upon being actuated from the proximal end of the catheter by a physician. Methods of positioning a catheter are also disclosed. The inventive device and method are particularly useful in catheter based procedures carried out in large body lumens or in cavities of body organs. In particular, the invention may be useful in delivering implants percutaneously through the left ventricle into the myocardium of the heart.

It should be understood however, that the foregoing description of the invention is intended merely to be illustrative thereof and that other modifications, embodiments and equivalents may be apparent to those who are skilled in the art without departing from its spirit. Having thus described the invention what we desire to claim and secure by Letters Patent is:  
     
         1 . A catheter positioning system comprising: 
 an elongate catheter having proximal and distal ends and at least one lumen extending there through, and it having a defined length;    at least one resilient member adjacent to distal end of the catheter configured to be selectively radially extended outward from the catheter; and    a control mechanism operatively associated with the resilient member and extending to the proximal end of the catheter where it is configured to be manipulated by a user to actuate the resilient member from a retracted to an extended position.    
     
     
         2 . A catheter positioning system as defined in  claim 1  further comprising: 
 a plurality of resilient members each having proximal and distal ends, all distal ends joined together and joined to the catheter at its distal end or adjacent its distal end and all proximal ends joined together and to the catheter at a position proximal to the distal end such that the resilient members lie parallel to the longitudinal axis of the catheter shaft when unloaded and such that the resilient members bow radially outward when a compressive load is applied to their distal ends.  
 
     
     
         3 . A catheter positioning system as defined in  claim 2  wherein the distal ends of the resilient members are joined to the catheter such that the distal end of the catheter is rotated through an angular displacement when the resilient members are bowed radially outward to an extended position.  
     
     
         4 . A catheter positioning system as defined in  claim 2  wherein the compressive force is applied by proximal movement of the control mechanism joined to the junction of the resilient member distal ends and the catheter.  
     
     
         5 . A catheter positioning system as defined in  claim 1  further comprising: 
 a plurality of resilient members each having proximal and distal ends, the proximal ends being an operative association with the control mechanism and the distal end being free such that movement of the control mechanism in the distal direction causes the distal ends of the members to advance radially outward away from the catheter to an extended position.  
 
     
     
         6 . A catheter positioning system as defined in  claim 5  wherein movement of the control mechanism and the distal are in the proximal direction causes the members to move radially inward to a retracted position such that the distal ends of the members do not protrude from the catheter.  
     
     
         7 . A catheter positioning system as defined in  claim 5  wherein each member is operatively associated with an independent control mechanism.  
     
     
         8 . A catheter positioning system as defined in  claim 5  wherein at least one of the resilient members is a tube having a lumen in fluid communication with a therapeutic agent that is pressurized from the proximal end of the catheter.  
     
     
         9 . A catheter positioning as defined in  claim 1  wherein at least one resilient member has a proximal end joined to a side wall of the catheter and a distal end that is free, the resilient member being naturally biased and arranged relative to the catheter such that the member distal end does not protrude from the catheter until elastically deformed by movement of an object through the lumen of the catheter.  
     
     
         10 . A catheter positioning system as defined in  claim 9  wherein the object moved through the catheter lumen is an ischemia treatment device.  
     
     
         11 . A catheter positioning system as defined in  claim 10  wherein the ischemia treatment device comprises a tissue implant and associated delivery device.  
     
     
         12 . A method of performing a catheter-based procedure to a particular treatment site within a patient comprising: 
 providing a catheter having a proximal end and a distal end and a radially extendible tissue engagement mechanism at its distal end;    navigating the catheter so that the distal end is adjacent to the intended tissue location;    causing the tissue engagement mechanism to extend into engagement with the tissue adjacent to treatment site; and    performing the medical procedure while maintaining the tissue engagement mechanism in its extended position.    
     
     
         13 . A method of performing a catheter-based procedure as defined in  claim 12  wherein the treatment site is the myocardium of the heart and the treatment is relieving the systems of ischemia.  
     
     
         14 . A method of performing a catheter-based procedure as defined in  claim 13  wherein the treatment of ischemia comprises advancing a tissue implant through the catheter and into the tissue at the treatment site.  
     
     
         15 . A method of performing a catheter-based procedure as defined in  claim 13  wherein the treatment for ischemia comprises delivering a therapeutic agent or cellular composition through the catheter to the treatment site.  
     
     
         16 . A method of performing a catheter-based procedure as defined in  claim 12  wherein the treatment site is the myocardium of the heart and the treatment is relieving the systems of ischemia.  
     
     
         17 . A method for forming a catheter-based procedure wherein the tissue engagement mechanism comprises a tube in communication with a therapeutic agent pressurized from the proximal end of the catheter when~the tissue engagement mechanism contacts the tissue to deliver the agent to the tissue.  
     
     
         18 . A method for delivering a tissue implant into myocardial tissue of the heart comprising: 
 providing a catheter having at least one lumen and proximal and distal ends and a radially extendible tissue engagement mechanism at its distal end configured to be extended by the presence of a device in the lumen at the distal end of the catheter;    navigating the catheter to the intended implant location in the myocardium;    inserting a delivery device carrying the implant through the lumen of the catheter while applying a distal force in a distal direction upon both the catheter and the delivery device such that the distal end of the catheter abuts the implant site; and    driving the implant through the distal end of the catheter to extend the catheter positioning mechanism to locate the distal end of the catheter so that the implant can be delivered to the intended tissue location.