Systems and Methods for Removing Undesirable Material Within a Circulatory System

Abstract

The present invention relates generally to improved systems and methods for removing undesirable material residing in vessels. More specifically, the present invention relates to systems and methods for using at least one cannula to remove to remove substantially en bloc, from a site of obstruction or interest, undesirable material without fragmentation and without excessive fluid loss.

1 . A system for removing undesirable material from within a vessel, the system comprising:
 a first cannula, the first cannula comprising:
 a proximal end; 
 a distal end; 
 a shaft comprising an inner layer, a reinforcement element, and an outer layer, and 
 an expandable distal end formed in part by extensions of the outer layer of the shaft, the expandable distal end further comprising reinforcement arms on top of the outer layer extensions, the expandable distal end further comprising a jacket between the outer layer extensions, and the expandable distal end capable of expanding to a diameter greater than the proximal end and capturing the undesirable material from the vessel; 
   a second cannula, the second cannula having a proximal end and a distal end, the distal end of the second cannula is placed in a spaced relation to the distal end of the first cannula;   a pump, the pump being in fluid communication with the proximal of the first cannula and the proximal end of the second cannula; and   a filter, the filter placed in fluid communication with the proximal end of the first cannula.   
     
     
         2 . The system of  claim 1 , further comprising an outer sheath, the outer sheath capable of being advanced towards the distal end of the first cannula or retracted towards the proximal end of the second cannula. 
     
     
         3 . The system of  claim 1 , wherein the reinforcement element comprises a flat coil allowing for a greater increased luminal diameter, as compared to a round wire. 
     
     
         4 . The system of  claim 1 , wherein the expandable distal end of the first cannula further comprises a proximal collar connected to the reinforcement arms. 
     
     
         5 . The system of  claim 1 , wherein the inner surface of the inner layer of the first cannula shaft has a higher friction coefficient than the inner surface of the expandable distal end. 
     
     
         6 . The system of  claim 1 , wherein the inner surface of the inner layer of the first cannula shaft has a lower friction coefficient than the inner surface of the expandable distal end. 
     
     
         7 . The system of  claim 1 , wherein the expandable distal end further comprises a fenestration hole. 
     
     
         8 . The system of  claim 1 , further comprising a third cannula capable of being advanced through a lumen of the first suction cannula. 
     
     
         9 . A system for removing undesirable material from within a vessel, the system comprising:
 a first cannula, the first cannula comprising:
 a proximal end; 
 a distal end; 
 a shaft comprising an inner layer, a reinforcement element, and an outer layer; 
 an expandable distal end comprising a collar connected to at least two pre-shaped reinforcement arms extending away from the first cannula in an expanded position, a jacket extending between the at least two pre-shaped reinforcement arms, and the expandable distal end capable of expanding to a diameter greater than the proximal end and capturing the undesirable material from the vessel; 
   a second cannula comprising a proximal end and a distal end, the distal end of the second cannula is placed in a spaced relation to the distal end of the first cannula;   a pump, the pump capable of simultaneously performing both a suction force and a driving force, the pump being in fluid communication with the proximal of the first cannula and the proximal end of the second cannula;   a filter, the filter placed in fluid communication with the proximal end of the first cannula; and   a reservoir for collection of the undesirable material and residual fluid that is captured during collection of the undesirable material.   
     
     
         10 . The system of  claim 9 , further comprising an outer sheath, the outer sheath capable of being advanced towards the distal end of the first cannula or retracted towards the proximal end of the second cannula. 
     
     
         11 . The system of  claim 9 , wherein the inner surface of the inner layer of the first cannula shaft has a higher friction coefficient than the inner surface of the expandable distal end. 
     
     
         12 . The system of  claim 9 , wherein the inner surface of the inner layer of the first cannula shaft has a lower friction coefficient than the inner surface of the expandable distal end. 
     
     
         13 . The system of  claim 9 , wherein the outer layer of the first cannula shaft has a lower friction coefficient than the expandable distal end. 
     
     
         14 . The system of  claim 9 , wherein the expandable distal end further comprises a fenestration hole. 
     
     
         15 . The system of  claim 9 , further comprising a third cannula capable of being advanced through a lumen of the first suction cannula. 
     
     
         16 . A method for removing undesirable material from a treatment site within a vessel, the method comprising:
 placing a first cannula for removing undesirable material from within a vessel, the first cannula comprising:
 a proximal end; 
 a distal end; 
 a shaft comprising an inner layer, a reinforcement element, and an outer layer; 
 an expandable distal end comprising a collar connected to at least two pre-shaped reinforcement arms extending away from the first cannula in an expanded position, the expandable distal end capable of expanding to a diameter greater than the proximal end and capturing the undesirable material from the vessel; and 
   placing a distal end of a second cannula in a spaced relation to the distal end of the first cannula;   activating a pump, the pump being in fluid communication with the proximal of the first cannula and the proximal end of the second cannula; and   filtering the undesirable material through a filter.   
     
     
         17 . The method of  claim 16 , further comprising the step of:
 advancing a third cannula through a lumen of the first cannula, the third cannula comprising a collar connected to at least two pre-shaped reinforcement arms extending away from the third cannula in an expanded position.