Aspiration catheter systems and methods of use

Abstract

Described are methods, systems, devices for facilitation of intraluminal medical procedures within the neurovasculature. A catheter advancement device includes a flexible elongate body having a proximal portion coupled to a proximal end region of the flexible elongate body and extending proximally to a proximal-most end of the catheter advancement element. A hardness of the flexible elongate body transitions proximally towards increasingly harder materials up to the proximal portion forming a first plurality of material transitions. At least a portion of the flexible elongate body is formed of a plurality of layers including a reinforcement layer. An outer diameter of the flexible elongate body is sized to be positioned coaxially within a lumen of a catheter such that a distal tip portion of the flexible elongate body extends distally beyond a distal end of the catheter to aid in delivery of the catheter to an intracranial vessel.

What is claimed is: 
     
         1 . A catheter system for performing a medical procedure in an intracranial vessel of a patient, the system comprising:
 a catheter comprising:
 a flexible distal luminal portion having a proximal end, a proximal end region, a proximal opening, a distal end, and a lumen extending between the proximal end and the distal end; and 
 a proximal extension extending proximally from a point of attachment adjacent the proximal opening, wherein the proximal extension is less flexible than the flexible distal luminal portion and is configured to control movement of the catheter, wherein the proximal extension has an outer diameter at the point of attachment that is smaller than an outer diameter of the distal luminal portion at the point of attachment; and 
   a catheter advancement element comprising:
 a flexible elongate body having a proximal end region, an outer diameter, a tapered distal tip portion, a distal opening, and a single lumen extending longitudinally through the flexible elongate body to the distal opening; and 
 a proximal portion extending proximally from the proximal end region to a proximal-most end of the catheter advancement element, 
   wherein the catheter advancement element is sized to be positioned through the proximal opening of the flexible distal luminal portion into the catheter lumen such that the tapered distal tip portion extends distal to the distal end of the distal luminal portion, and wherein the flexible distal luminal portion and the proximal extension are configured to pass through a guide sheath, and   wherein the distal luminal portion of the catheter has a length that is greater than 40 cm up to less than a working length of the guide sheath through which the system is advanced, the length sufficient to allow the distal end of the distal luminal portion to reach a target site within the intracranial vessel and the point of attachment between the distal luminal portion and the proximal extension be positioned within a vessel proximal to the brachiocephalic take-off.   
     
     
         2 . The system of  claim 1 , wherein the length of the distal luminal portion is sufficient to position the distal end of the distal luminal portion distal to the carotid siphon when the point of attachment is positioned proximal to the brachiocephalic take-off. 
     
     
         3 . The system of  claim 1 , wherein the proximal portion of the catheter advancement element is coupled to the proximal end region of the flexible elongate body at a point of attachment, the proximal portion extending proximally from the point of attachment to the proximal-most end of the catheter advancement element. 
     
     
         4 . The system of  claim 1 , wherein the proximal portion of the catheter advancement element has a single lumen extending through an entire length of the proximal portion that communicates with the single lumen of the elongate body. 
     
     
         5 . The system of  claim 3 , wherein the elongate body has a length sufficient to allow the point of attachment between the elongate body and the proximal portion to remain within or proximal to the aortic arch when assembled with the catheter, the distal end of the catheter positioned near the target site within the intracranial vessel. 
     
     
         6 . The system of  claim 5 , wherein the proximal opening of the flexible elongate body is through a sidewall of the flexible elongate body and is located a distance distal to the proximal portion of the catheter advancement element coupled to the proximal end region. 
     
     
         7 . The system of  claim 6 , wherein the distance is about 10 cm from the distal tip portion up to about 20 cm from the distal tip portion. 
     
     
         8 . The system of  claim 1 , wherein the assembled catheter system is pre-packaged with the catheter advancement element positioned within the lumen of the distal luminal portion such that the proximal portion of the flexible elongate body is locked with the proximal extension of the catheter. 
     
     
         9 . The system of  claim 1 , wherein at least a portion of the proximal extension of the catheter is color-coded. 
     
     
         10 . The system of  claim 1 , wherein the single lumen of the flexible elongate body is sized to accommodate a guidewire. 
     
     
         11 . The system of  claim 10 , wherein the flexible elongate body comprises a proximal opening sized to accommodate the guidewire. 
     
     
         12 . The system of  claim 11 , wherein the proximal opening of the flexible elongate body is located within the proximal end region of the flexible elongate body. 
     
     
         13 . The system of  claim 1 , wherein a flexibility of the flexible elongate body transitions to be less flexible proximally towards the proximal portion forming a first plurality of material transitions. 
     
     
         14 . The system of  claim 1 , wherein the distal tip portion comprises a material having a material hardness that is no more than 35 D, and wherein the proximal end region of the elongate body comprises a material having a material hardness that is between 55 D to 72 D. 
     
     
         15 . The system of  claim 1 , wherein the elongate body comprises a first segment including the distal tip portion having a hardness of no more than 35 D, wherein the elongate body comprises a second segment located proximal to the first segment having a hardness of no more than 55 D, and wherein the elongate body comprises a third segment located proximal to the second segment having a hardness of no more than 72 D. 
     
     
         16 . The system of  claim 15 , wherein the proximal portion couples to the elongate body within the third segment. 
     
     
         17 . The system of  claim 15 , wherein the first segment is unreinforced and the third segment is reinforced. 
     
     
         18 . The system of  claim 17 , wherein the second segment is at least partially reinforced. 
     
     
         19 . The system of  claim 15 , wherein the first, second, and third segments combine to form an insert length of the elongate body. 
     
     
         20 . The system of  claim 1 , wherein a flexibility of the flexible distal luminal portion transitions to be less flexible proximally towards the proximal extension, wherein the flexible distal luminal portion comprises a second plurality of material transitions, wherein the flexible elongate body is positioned within the lumen of the catheter such that the distal tip portion of the flexible elongate body extends distally beyond the distal end of the catheter such that the first plurality of material transitions of the flexible elongate body are staggered relative to and do not overlap with the second plurality of material transitions of the flexible distal luminal portion. 
     
     
         21 . The system of  claim 1 , wherein the length of the distal luminal portion allows for the distal end of the distal luminal portion to extend distal to a carotid siphon into the cerebral portion of an internal carotid artery while the proximal end of the distal luminal portion remains within the descending aorta. 
     
     
         22 . The system of  claim 1 , wherein the lumen of the distal luminal portion of the catheter is defined by a wall and a distal end region of the proximal extension is sandwiched within layers of the wall of the distal luminal portion. 
     
     
         23 . The system of  claim 1 , wherein the flexible elongate body incorporates a segment located distal to the proximal end region and proximal to the tapered distal tip portion, wherein the outer diameter of the flexible elongate body is within the segment, and wherein an outer diameter of the proximal end region is smaller than the outer diameter of the flexible elongate body within the segment. 
     
     
         24 . The system of  claim 1 , wherein the proximal portion of the catheter advancement element and the proximal extension of the catheter extend side-by-side when assembled as a system. 
     
     
         25 . The system of  claim 1 , wherein the proximal portion of the catheter advancement element comprises a hypotube having a distal end coupled to the flexible elongate body. 
     
     
         26 . The system of  claim 1 , wherein the proximal portion is a solid metal wire or ribbon. 
     
     
         27 . The system of  claim 1 , further comprising a tab positioned on a proximal end of the proximal extension of the catheter, wherein the tab is positioned relative to the proximal opening to prevent over-insertion of the catheter relative to the guide sheath so as to maintain the proximal opening within the guide sheath. 
     
     
         28 . The system of  claim 27 , wherein the tab is sized to abut against a connector on the guide sheath preventing further advancement of the distal luminal portion of the catheter through the guide sheath.