Hydraulic displacement and removal of thrombus clots, and catheters for performing hydraulic displacement

Abstract

Clot removal from a patient's vessel, such as an artery, are described using aspiration and hydraulic forces supporting the removal process. Hydraulic forces can be generated by occluding the vessel distal to the clot and delivering liquid between the clot and the occlusive device. The aspiration catheter is positioned proximal to the clot. Catheters designed to facilitate the delivery of hydraulic forces can be based on single lumen designs or dual lumen designs. The catheters may have a fixed internal wire, or in some embodiments the catheters can ride over a wire with a valve/seal positioned to restrict flow into or out from the guide lumen such that the guide lumen can further function for balloon inflation and/or for infusion of liquid.

What is claimed is: 
     
         1 . A catheter comprising:
 a tubular shaft comprising a single lumen and a distal end;   a proximal fitting;   a balloon having a proximal end and an interior, wherein the balloon is attached at or near the distal end of the tubular shaft wherein the interior of the balloon is in fluid communication with the central lumen,   wherein the tubular shaft comprises one or more infusion ports proximal to the balloon within about 5 centimeters from the proximal end of the balloon.   
     
     
         2 . The catheter of  claim 1  further comprising an integral fixed wire extending a majority of the length of the catheter shaft and having a distal end secured at or near the distal end of the catheter shaft. 
     
     
         3 . The catheter of  claim 2  wherein the fixed wire is secured at its distal end with an adhesive/polymer plug and a coil extends distally from the tubular shaft. 
     
     
         4 . The catheter of  claim 2  wherein fixed wire has a proximal end floating within a tubular element attached to proximal fitting that constrains the proximal end of the wire. 
     
     
         5 . The catheter of  claim 2  wherein the spacing between the wire and the tubular shaft at the one or more infusion ports is from about 0.005 in to about 0.0089 in. 
     
     
         6 . The catheter of  claim 1  wherein the distal end of the catheter shaft comprises a wire extending from the catheter shaft, or the distal end of the catheter shaft comprises a wire port and a valve/seal is located proximal to the wire port with a configuration to engage a wire to reduce or eliminate liquid flow to or from the wire port. 
     
     
         7 . The catheter of  claim 1  wherein a polymer valve controls flow from the one or more infusion ports. 
     
     
         8 . The catheter of  claim 7  wherein the polymer valve comprised an elastic cover attached along an edge around the circumference of the catheter. 
     
     
         9 . The catheter of  claim 7  further comprising a wire within the tubular shaft. 
     
     
         10 . The catheter of  claim 9  wherein the wire is attached at its distal end with an adhesive/polymer plug and a coil extends distally from the tubular shaft. 
     
     
         11 . The catheter of  claim 9  wherein the tubular shaft comprises a distal segment, a proximal segment and a taper segment connecting the distal segment and the proximal segment, wherein the proximal segment has an approximately constant diameter, the distal segment has an approximately constant diameter smaller than the diameter of the proximal segments, and the taper segment has a gradient in diameter connecting the distal segment and the proximal segment, and wherein the wire has two or more tapered sections. 
     
     
         12 . A catheter comprising:
 a shaft comprising a tubular element and proximal fittings, the tubular element having a distal end, a first lumen and a second lumen, and not having a distinct guidewire lumen; and   a balloon having a proximal end and an interior secured to the outer surface of the shaft at or near the distal end of the shaft wherein the interior of the balloon is in fluid communication with the first lumen,   wherein the shaft comprises infusion ports proximal to the distal end of the balloon and within about 5 centimeters of the proximal end of the balloon, the infusion ports being in fluid communication with the second lumen and the shaft being free of infusion ports distal to the balloon and of additional balloons, and   wherein proximal fittings comprising a Y-branch fitting providing a first connector for attachment of an infusion fluid source for delivery through the infusion ports and a second connector for attachment of a device configured for delivery and/or removal of balloon expansion fluid.   
     
     
         13 . The catheter of  claim 12  wherein the distal end of the catheter shaft comprises a distal wire or coil extending from the catheter shaft, or the distal end of the catheter shaft comprises a guidewire port and a valve/seal is located at or near to the guidewire port with a configuration to engage a guidewire to reduce or eliminate liquid flow to or from the guidewire port. 
     
     
         14 . The catheter of  claim 12  further comprising an integral wire extending a majority of the length of the catheter shaft and having a distal end secured at or near the distal end of the catheter shaft. 
     
     
         15 . The catheter of  claim 12  wherein the tubular element is formed to have the first lumen and the second lumen in a unitary structure. 
     
     
         16 . The catheter of  claim 12  wherein the tubular element comprises an inner tubular shaft and an outer tubular shaft. 
     
     
         17 . The catheter of  claim 16  wherein the second lumen comprises the space between the inner tubular shaft and the outer tubular shaft. 
     
     
         18 . The catheter of  claim 16  wherein the first lumen comprises the space between the inner tubular shaft and the outer tubular shaft. 
     
     
         19 . The catheter of  claim 12  wherein a polymer valve controls flow from the one or more infusion ports. 
     
     
         20 . A catheter comprising:
 a balloon;   a catheter shaft comprising infusion ports and a dual lumen structure with a guidewire lumen and an auxiliary lumen, and a valve configured to close the distal end of the guidewire lumen when a guidewire is absent; and   proximal fittings with connections to an inflation fluid source and to an infusion liquid source,   
       wherein the auxiliary lumen is in fluid communication either with the interior of the balloon and the connection to the inflation fluid source, or with the infusion ports and the infusion liquid source. 
     
     
         21 . The catheter of claim  25  wherein the auxiliary lumen is in fluid communication with the interior of the balloon and the connection to the inflation fluid source. 
     
     
         22 . The catheter of claim  25  wherein the auxiliary lumen is in fluid communication with the infusion ports and the infusion liquid source.