Method of restoring blood flow through an obstructed blood vessel of the brain

Abstract

An acute stroke recanalization system and processes include catheter-based improved reconstrainable or tethered neurological devices which are deliverable through highly constricted and tortuous vessels, crossing the zone associated with subject thrombi/emboli, where deployment impacts, addresses or bridges the embolus, compacting the same into luminal walls which enables perfusion and lysis of the embolus, while the improved neurological medical device itself remains contiguous with the delivery system acting as a filter, basket or stand alone stenting mechanism, depending on the status of the embolus and other therapeutic aspects of the treatment being offered for consideration.

1 . A method of restoring blood flow through an obstructed blood vessel of the cerebral vasculature, comprising:
 identifying an obstructed blood vessel within the cerebral vasculature of a patient, the obstructed blood vessel having an occlusive embolus;   inserting a catheter-based revascularization system within the obstructed blood vessel;
 wherein the catheter-based revascularization system comprises an outer catheter and an inner catheter longitudinally moveable with respect to each other; 
 wherein the inner catheter comprises a pusher and a self-expandable revascularization device eccentrically tethered to a distal end of the pusher; 
 wherein the self-expandable revascularization device comprises a generally cylindrical body having an open proximal end, an open distal end, and a plurality of struts that form a plurality of cells between the proximal and distal ends; 
   positioning the outer catheter at a location distal to the embolus;   retracting the outer catheter to deploy the self-expandable revascularization device at the location of the embolus thereby compressing the embolus against a luminal wall of the blood vessel and restoring flow through the blood vessel;
 wherein the restored blood flow facilitates natural lysis of the embolus; 
 wherein the natural lysis and compression of the embolus cause fragmentation of at least a portion of the embolus into a plurality of embolic fragments, 
 wherein one or more of said embolic fragments pass through the open distal end of the self-expandable revascularization device downstream of the embolus; and 
 wherein the self-expandable revascularization device exerts continuous radial pressure at the location of the embolus to further facilitate blood flow through the blood vessel as the embolus lyses; 
   resheathing the revascularization device within the outer catheter; and   removing the revascularization system from the patient.   
     
     
         2 . The method of  claim 1 , wherein the revascularization device is permanently tethered to a distal end of the pusher. 
     
     
         3 . The method of  claim 1 , wherein the revascularization device is detachably tethered to a distal end of the pusher. 
     
     
         4 . The method of  claim 1 , wherein the revascularization device comprises radiopaque markers configured for tracking of the revascularization device. 
     
     
         5 . The method of  claim 4 , further comprising tracking the revascularization device to confirm proper positioning with respect to the embolus. 
     
     
         6 . The method of  claim 1 , wherein deploying the self-expandable revascularization device at the location of the embolus comprises creating an immediate flow channel within the blood vessel of at least about 50% of the diameter of the blood vessel of the cerebral vasculature. 
     
     
         7 . The method of  claim 1 , wherein the pusher comprises a variable-pitch hypotube. 
     
     
         8 . The method of  claim 1 , wherein the pusher comprises a wire. 
     
     
         9 . The method of  claim 1 , wherein at least a portion of said inner catheter comprises a flexible material configured to permit flexion and extension to navigate through curved vessels of the cerebral vasculature. 
     
     
         10 . The method of  claim 1 , further comprising infusing lytic agents to the location of the embolus through the revascularization system. 
     
     
         11 . The method of  claim 1 , further comprising removing at least a portion of the embolus captured by the revascularization device. 
     
     
         12 . The method of  claim 1 , wherein the revascularization device comprises a self-expanding microstent. 
     
     
         13 . The method of  claim 1 , further comprising morselizing at least a portion of the embolus by mechanical manipulation of the revascularization device. 
     
     
         14 . The method of  claim 1 , wherein inserting the catheter-based revascularization system within the obstructed blood vessel comprises advancing the revascularization system over a guidewire proximate a location of the embolus. 
     
     
         15 . A method of restoring blood flow through an obstructed blood vessel of the brain to treat acute ischemic stroke, comprising:
 identifying an obstructed blood vessel within the cerebral vasculature of a patient, the obstructed blood vessel having an embolus;   inserting a catheter-based revascularization system within the obstructed blood vessel;
 wherein the catheter-based revascularization system comprises an outer catheter and an inner catheter longitudinally moveable with respect to each other; 
 wherein the inner catheter comprises a pusher and a self-expandable revascularization device tethered to a distal end of the pusher; 
 wherein the self-expandable revascularization device comprises an open proximal end, an open distal end, and a plurality of struts that form a plurality of cells between the proximal and distal ends; 
   positioning the outer catheter at a location distal to the embolus;   retracting the outer catheter, thereby deploying the self-expandable revascularization device at the location of the embolus, thereby compressing the embolus or lesion against a luminal wall of the obstructed blood vessel and restoring flow through the obstructed blood vessel;
 wherein the restored blood flow facilitates natural lysis of the embolus; 
 wherein the natural lysis and compression of the embolus cause fragmentation of at least a portion of the embolus into a plurality of fragments, 
 wherein one or more of said fragments pass through the open distal end of the self-expandable revascularization device downstream of the embolus; and 
 wherein the self-expandable revascularization device exerts continuous radial pressure at the location of embolus to further facilitate blood flow through the blood vessel as the embolus lyses; 
   resheathing the revascularization device within the outer catheter; and   removing the revascularization system from the patient.   
     
     
         16 . The method of  claim 15 , wherein the self-expandable revascularization device is generally cylindrical and eccentrically tethered to the distal end of the pusher via a plurality of tethered lines. 
     
     
         17 . The method of  claim 15 , further comprising morselizing at least a portion of the embolus by mechanical manipulation of the revascularization device. 
     
     
         18 . The method of  claim 15 , further comprising removing at least a portion of the embolus captured by the revascularization device. 
     
     
         19 . The method of  claim 15 , wherein deploying the self-expandable revascularization device at the location of the embolus comprises creating an immediate flow channel within the blood vessel of at least about 50% of the diameter of the blood vessel of the cerebral vasculature. 
     
     
         20 . The method of  claim 15 , wherein inserting a catheter-based revascularization system within the obstructed blood vessel comprises advancing the revascularization system over a guidewire proximate a location of the embolus.