Readily exchangeable perfusion dilatation catheter

Abstract

A perfusion-type dilatation catheter which can be rapidly exchanged for another catheter without the need for exchange wires or guidewire extension wires. The dilatation catheter has an elongated catheter body with a distal guidewire port in the distal end of the catheter and a proximal guidewire port at least 10 cm but not more than 50 cm from the distal port. The catheter body has a first inflation lumen which extends from the proximal end of the catheter body to the interior of a dilatation balloon adjacent the distal end of the catheter body. A second, much shorter inner lumen is disposed between the proximal and distal guidewire ports and is adapted to slidably receive a guidewire. A plurality of perfusion ports are provided both proximal and distal to the balloon which are in fluid communication with the second inner lumen so that when the balloon is inflated within a patient's vascular system, blood will flow through the proximal perfusion ports and the second inner lumen and out the distal perfusion ports to minimize ischemic conditions distal to the catheter. A stiffening member is disposed within the catheter body proximal to the proximal guidewire port to provide improved pushability. The distal portion of the inflation lumen should have a transverse cross-sectional area of about 3 to about 20×10-5 inch2 and should not be greater than one-third the cross-sectional area of the perfusion lumen.

What is claimed:  
     
         1 . An intravascular catheter for performing a vascular procedure within a patient's vascular system, comprising: 
 a) an elongated catheter body having proximal and distal ends and an expandable member proximally adjacent the distal end thereof and a relatively short inner lumen adapted to receive a guidewire which extends between a distal guidewire port provided in the distal end of the catheter body and a proximal guidewire port which is provided in the catheter body and which is disposed at least 10 cm but not more than 50 cm from the distal guidewire port;    b) at least one proximal perfusion port located between the proximal guidewire port and the expandable member and at least one distal perfusion port located between the expandable member and the distal end of the catheter body, the perfusion ports being in fluid communication with the inner lumen adapted to receive a guidewire; and    c) means to stiffen a portion of the catheter body proximal to the proximal guidewire port to provide the catheter with improved pushability.    
     
     
         2 . The intravascular catheter of  claim 1  wherein the expandable member is an inflatable, relatively inelastic balloon suitable for dilating a stenosis.  
     
     
         3 . The intravascular catheter of  claim 2  wherein the balloon is formed from a plastic resin selected from the group consisting of polyethylene and polyethylene terephthalate.  
     
     
         4 . The intravascular catheter of  claim 2  wherein the inflation lumen extends distally from the proximal end of the catheter body to the interior of the balloon.  
     
     
         5 . The intravascular catheter of  claim 1  wherein the means to stiffen the catheter body proximal to the proximal guidewire port is a rod tightly fitted within an inner lumen of the catheter body which extends from the proximal end thereof to a location proximal to the proximal guidewire port.  
     
     
         6 . The intravascular catheter of  claim 4  wherein the inflation lumen has a D-shaped transverse cross-section and a thin wire extends within the D-shaped inflation lumen to prevent the retention of air bubbles in a corner of the inflation lumen.  
     
     
         7 . The intravascular catheter of  claim 1  wherein the proximal guidewire port is disposed about 12 to about 40 cm from the distal guidewire port.  
     
     
         8 . The intravascular catheter of  claim 1  wherein a slit is provided in the wall of the catheter body defining at least in part the second inner lumen which extends from the proximal guidewire port to a location proximal to the proximal perfusion ports.  
     
     
         9 . The intravascular catheter of  claim 1  wherein there are about 6 to about 20 proximal perfusion ports in the catheter wall.  
     
     
         10 . The intravascular catheter of  claim 1  wherein there are about 4 to about 12 distal perfusion ports provided in the catheter wall.  
     
     
         11 . The intravascular catheter of  claim 4  wherein the inflation lumen in the distal portion of the catheter body has a cross-sectional area of about 3 to about 20×10-5 inch2.  
     
     
         12 . The intravascular catheter of  claim 11  wherein the inflation lumen has a cross-sectional area not greater than about ⅓ of the cross-sectional area of the relatively short inner lumen adapted to receive a guidewire.  
     
     
         13 . The intravascular catheter of  claim 11  wherein the inflation lumen in the distal portion of the catheter body having a cross-sectional area of about 3 to about 20×10-5 inch2 is less than 30 cm in length.  
     
     
         14 . The method of performing a vascular procedure in a patient's vascular system, comprising: 
 a) providing a vascular catheter having an expandable member on the distal end thereof and a relatively short inner lumen therein extending in a distal portion of the catheter body between a distal guidewire port and a proximal guidewire port about 10 to about 50 cm proximal from the distal guidewire port and perfusion ports in the wall of the catheter body in fluid communication with the short inner lumen between the proximal guidewire port and the distal guidewire port in the distal end of the catheter body;    b) advancing the vascular catheter within the patient's vascular system over a guidewire slidably disposed within the relatively short inner lumen to a location within the patient's vascular system;    c) expanding the expandable member on the vascular catheter to at least partially occlude the patient's blood vessel at the location causing blood to flow through the proximal perfusion ports and the second inner lumen and out the distal perfusion ports; and    d) contracting the expanded expandable member to facilitate removal of the catheter from the patient.    
     
     
         15 . The method of  claim 11  wherein the guidewire is at least partially removed from the portion of the second inner lumen between the proximal and distal perfusion ports to avoid impeding blood flow through the second inner lumen.  
     
     
         16 . A method of  claim 11  wherein: 
 a) the catheter is removed from the patient by holding the guidewire in place at a first location outside of the patient and proximally moving the catheter over the guidewire until the proximal guidewire port thereof is immediately adjacent said first holding location; and  
 b) holding the guidewire at a second location outside of the patient adjacent the distal guidewire port of the catheter and then removing the catheter from the guidewire.  
 
     
     
         17 . A method of  claim 16  including: 
 a) providing a second dilatation catheter having an expandable member on the distal end thereof and a relatively short inner lumen therein extending in a distal portion of the catheter body between a distal guidewire port and a proximal guidewire port about 10 to about 50 cm proximal from the distal guidewire port and perfusion ports in the wall of the catheter body in fluid communication with the short inner lumen between the proximal guidewire port and the distal guidewire port in the distal end of the catheter body;  
 b) mounting the second dilatation catheter onto the guidewire by passing the proximal end of the guidewire through the second lumen until a portion thereof extends out of the proximal guidewire port;  
 c) holding the portion of the guidewire extending out of the proximal port of the catheter; and  
 d) advancing the catheter over the guidewire into and through the vascular system of the patient until the catheter is positioned at a desired location therein.  
 
     
     
         18 . An intravascular catheter for performing a vascular procedure within a patient's vascular system, comprising: 
 a) an elongated catheter body having proximal and distal ends and an expandable member proximally adjacent the distal end thereof and a relatively short inner lumen adapted to receive a guidewire which extends between a distal guidewire port provided in the distal end of the catheter body and a proximal guidewire port which is provided in the catheter body and which is disposed at least 10 cm but not more than 50 cm from the distal guidewire port;    b) at least one proximal perfusion port located between the proximal guidewire port and the expandable member and at least one distal perfusion port located between the expandable member and the distal end of the catheter body, the perfusion ports being in fluid communication with the inner lumen adapted to receive a guidewire; and    c) means to stiffen a portion of the catheter body proximal to the proximal guidewire port to provide the catheter with improved pushability.