Embolectomy Catheters And Methods For Treating Stroke And Other Small Vessel Thromboembolic Disorders

Abstract

Embolectomy catheters, rapid exchange microcatheters, systems and methods for removing clots or other obstructive matter (e.g., thrombus, thromboemboli, embolic fragments of atherosclerotic plaque, foreign objects, etc.) from blood vessels. This invention is particularly useable for percutaneous removal of thromboemboli or other obstructive matter from small blood vessels of the brain, during an evolving stroke or period of cerebral ischemia. In some embodiments, the embolectomy catheters of this invention are advanceable with or over a guidewire which has been pre-inserted through or around the clot. Also, in some embodiments, the embolectomy catheters include clot removal devices which are deployable from the catheter after the catheter has been advanced at least partially through the clot. The clot removal device may include a deployable wire nest that is designed to prevent a blood clot from passing therethrough. The delivery catheter may include telescoping inner and outer tubes, with the clot removal device being radially constrained by the outer tube. Retraction of the outer tube removes the constraint on the clot removal device and permits it to expand to its deployed configuration. An infusion guidewire is particularly useful in conjunction with the embolectomy catheter, and permits infusion of medicaments or visualization fluids distal to the clot.

What is claimed is: 
     
         1 . A method of removing a portion of an obstruction within a vessel comprising:
 inserting a guidewire into a vessel of a patient;   advancing the guidewire towards an obstruction;   advancing a catheter comprising an obstruction disrupting device over the guidewire until the catheter is proximate the obstruction;   deploying the obstruction disrupting device; and   retracting the catheter from the vessel.   
     
     
         2 . The method of  claim 1  wherein the step of advancing a catheter over the guidewire until the obstruction disrupting device of the catheter contacts the obstruction comprises advancing at least a portion of the catheter into the obstruction. 
     
     
         3 . The method of  claim 1  wherein the step of advancing a catheter over the guidewire until the obstruction disrupting device of the catheter contacts the obstruction comprises advancing the catheter through the obstruction so as to position the obstruction disrupting device within at least a portion of the obstruction. 
     
     
         4 . The method of  claim 1  wherein the step of deploying the obstruction disrupting device comprises partially deploying the device. 
     
     
         5 . The method of  claim 1  wherein the step of deploying the obstruction disrupting device comprises deploying the device into the obstruction. 
     
     
         6 . The method of  claim 1  wherein the step of deploying the obstruction disrupting device comprises transforming the device from a contracted configuration to an expanded configuration. 
     
     
         7 . The method of  claim 1  wherein the step of deploying the obstruction disrupting device comprises expanding a fluid permeable element of the obstruction disrupting device. 
     
     
         8 . The method of  claim 1  wherein the step of retracting the catheter from the vessel comprises transforming the obstruction disrupting device of the catheter from an expanded configuration to a contracted configuration. 
     
     
         9 . The method of  claim 1  further comprising the repeating the step of deploying the obstruction disrupting device. 
     
     
         10 . The method of  claim 1  further comprising the step of administering a pharmacological treatment within the vessel. 
     
     
         11 . The method of  claim 9  wherein the step of administering a pharmacological treatment within the vessel comprises administering a pharmacological selected from the group of pharmacologicals consisting of: lysing agent, dissolving agent, thrombolityc agent, and anticoagulant agent. 
     
     
         12 . A method for reestablishing blood flow through a vessel comprising:
 advancing a guidewire through a vessel towards a vessel obstruction;   sliding a matter disrupting device over the guidewire towards the vessel obstruction;   penetrating the vessel obstruction with at least a portion of a matter engaging element of the matter disrupting device;   expanding the matter engaging element of the matter disrupting device;   contracting the matter engaging element of the matter disrupting device; and   withdrawing the matter engaging device from the vessel.   
     
     
         13 . The method of  claim 12  wherein the step of sliding a matter disrupting device over the guidewire comprises sliding at least a portion of a catheter over the guidewire. 
     
     
         14 . The method of  claim 12  wherein the step of penetrating the vessel obstruction with at least a portion of a matter engaging element of the matter disrupting device comprises passing a portion of the matter disrupting device through the vessel obstruction. 
     
     
         15 . The method of  claim 12  wherein the step of penetrating the vessel obstruction with at least a portion of a matter engaging element of the matter disrupting device comprises positioning a portion of the matter engaging element through the vessel obstruction. 
     
     
         16 . The method of  claim 12  wherein the step of expanding the matter engaging element of the matter disrupting device comprises expanding a permeable matter engaging element. 
     
     
         17 . The method of  claim 12  wherein the step of expanding the matter engaging element of the matter disrupting device comprises partially expanding the matter engaging element. 
     
     
         18 . The method of  claim 12  further comprising the step of repeating the steps of expanding the matter engaging element of the matter disrupting device and contracting the matter engaging element of the matter disrupting device. 
     
     
         19 . The method of  claim 12  further comprising the step of administering a pharmacological treatment within the vessel. 
     
     
         20 . The method of  claim 19  wherein the step of administering a pharmacological treatment within the vessel comprises administering a pharmacological selected from the group of pharmacologicals consisting of: lysing agent, dissolving agent, thrombolityc agent, and anticoagulant agent. 
     
     
         21 . A method of treating an obstructed vessel comprising:
 inserting a guidewire into a vessel of a patient;   advancing the guidewire towards an obstruction;   advancing an obstruction disrupting device over the guidewire until the device contacts the obstruction;   expanding the obstruction disrupting device against the obstruction;   contracting the obstruction disrupting device;   repeating the steps of expanding and contracting; and   retracting the obstruction disrupting device from the vessel.   
     
     
         22 . The method of  claim 21  wherein the step of advancing an obstruction disrupting device over the guidewire until the device of the catheter contacts the obstruction comprises advancing at least a portion of the device into the obstruction. 
     
     
         23 . The method of  claim 21  wherein the step of advancing an obstruction disrupting device over the guidewire until the device of the catheter contacts the obstruction comprises advancing the device through the obstruction so as to position the device within at least a portion of the obstruction. 
     
     
         24 . The method of  claim 21  wherein the step of expanding the obstruction disrupting device comprises partially expanding the device. 
     
     
         25 . The method of  claim 21  wherein the step of expanding the obstruction disrupting device comprises inflating a balloon. 
     
     
         26 . The method of  claim 21  wherein the step of expanding the obstruction disrupting device comprises releasing the obstruction disrupting device from a catheter. 
     
     
         27 . The method of  claim 21  wherein the step of expanding the obstruction disrupting device comprises expanding a fluid permeable element of the obstruction disrupting device. 
     
     
         28 . The method of  claim 21  wherein the step of retracting the obstruction disrupting device from the vessel comprises withdrawing the obstruction disrupting device into a catheter and retracting the catheter from the vessel. 
     
     
         29 . The method of  claim 21  wherein repeating the steps of expanding and contracting comprises axially repositioning the obstruction disrupting device prior to expanding the obstruction disrupting device. 
     
     
         30 . The method of  claim 21  further comprising the step of administering a pharmacological treatment within the vessel. 
     
     
         31 . The method of  claim 30  wherein the step of administering a pharmacological treatment within the vessel comprises administering a pharmacological selected from the group of pharmacologicals consisting of: lysing agent, dissolving agent, thrombolityc agent, and anticoagulant agent.