Duet stent deployment system and method of performing a transjugular intrahepatic portosystemic shunting procedure using same

Abstract

A duet stent deployment system is used in a transjugular intrahepatic portosystemic shunt procedure. The device has a versatility of adjusting to a patient's anatomy in vivo. The system includes exactly two self expanding stents mounted on an inner catheter and covered by an outer sheath that is moved among a pre-deployment configuration, a first deployment configuration and a second deployment configuration to position the stents in an overlapping configuration from the portal vein, through a shunt and into the hepatic vein, and terminating at the junction with the vena cava.

What is claimed is: 
     
         1 . A duet stent deployment system comprising:
 an inner catheter;   exactly two stents mounted on a distal segment of the inner catheter, and the two stents include a primary stent and a secondary stent;   an outer sheath slidably mounted on the inner catheter, and being movable along an axis of the inner catheter from a predeployment configuration to a first deployment configuration, and then from the first deployment configuration to a second deployment configuration;   the primary and secondary stents being covered by the outer sheath in the predeployment configuration;   the primary stent being uncovered but the secondary stent being covered by the outer sheath in the first deployment configuration;   the primary and secondary stents being uncovered by the outer sheath at the second deployment configuration;   wherein the primary stent includes a sleeve covering, and the secondary stent is longer than the primary stent, and both the primary stent and the secondary stent are self-expanding stents.   
     
     
         2 . The duet stent deployment system of  claim 1  wherein one of the outer sheath and the inner catheter includes a ruler measurement segment defined by radiopaque markers equally spaced along the axis. 
     
     
         3 . The duet stent deployment system of  claim 2  wherein the ruler measurement segment is less than twelve centimeters in length. 
     
     
         4 . The duet stent deployment system of  claim 1  wherein the primary stent is about four centimeters long; and
 the secondary stent is less than eight centimeters long. 
 
     
     
         5 . The duet stent deployment system of  claim 1  wherein the secondary stent includes a sleeve covering. 
     
     
         6 . The duet stent deployment system of  claim 1  wherein the primary and secondary stents have identical expanded outside diameters. 
     
     
         7 . The duet stent deployment system of  claim 1  including a first lock that is moveable between a locked position and an unlocked position;
 a second lock that is moveable between a locked position and an unlocked position; 
 the duet stent deployment system being locked against movement from the predeployment configuration to the first deployment configuration when the first lock is in the locked position; and 
 the duet stent deployment system being locked against movement from the first deployment configuration to the second deployment configuration when the second lock is in the locked position. 
 
     
     
         8 . The duet stent deployment system of  claim 1  wherein the outer sheath includes a ruler measurement segment defined by radiopaque markers equally spaced along the axis;
 the primary stent is about four centimeters long, and the secondary stent is less than eight centimeters long but longer than the primary stent. 
 
     
     
         9 . The duet stent deployment system of  claim 8  including a hub attached to a proximal end of the inner catheter;
 the outer sheath being connected to a handle slidably mounted on the inner catheter; 
 a first lock that is moveable between a locked position in contact with the handle and an unlocked position; 
 a second lock that is moveable between a locked position in contact with the handle and an unlocked position; 
 the duet stent deployment system being locked against movement from the predeployment configuration to the first deployment configuration when the first lock is in the locked position; and 
 the duet stent deployment system being locked against movement from the first deployment configuration to the second deployment configuration when the second lock is in the locked position. 
 
     
     
         10 . The duet stent deployment system of  claim 9  wherein the ruler measurement segment is less than twelve centimeters in length; and
 the secondary stent includes a sleeve covering. 
 
     
     
         11 . A method of performing a transjugular intrahepatic shunting procedure with duet stent deployment system that includes exactly two stents mounted on a distal segment of an inner catheter, and the two stents include a primary stent and a secondary stent; an outer sheath slidably mounted on the inner catheter, and being movable along an axis of the inner catheter from a predeployment configuration to a first deployment configuration, and then from the first deployment configuration to a second deployment configuration; and the primary stent includes a sleeve covering, and the secondary stent is longer than the primary stent, and both the primary stent and the secondary stent are self-expanding stents, and the method comprising the steps of:
 maneuvering the duet stent deployment system in the predeployment configuration to a position at which the primary stent is positioned within a shunt extending between a hepatic vein and a portal vein;   reconfiguring the duet stent deployment system from the predeployment configuration to the first deployment configuration to release the primary stent in the shunt;   repositioning the duet deployment system to a position at which a distal end of the secondary stent is positioned inside the primary stent, and a proximal end of the secondary stent is positioned at a junction of the hepatic vein to the a vena cava; and   reconfiguring the duet stent deployment system from the first deployment configuration to the second deployment configuration to release the secondary stent to extend from the junction to a position inside the primary stent.   
     
     
         12 . The method of  claim 11  including a step of measuring a distance from the junction to the shunt using a ruler measurement segment of the outer sheath, which is defined by radiopaque markers equally spaced along the axis, prior to the step of reconfiguring the duet stent deployment system from the first deployment configuration to the second deployment configuration. 
     
     
         13 . The method of  claim 11  wherein the step of reconfiguring the duet stent deployment system from the first deployment configuration to the second deployment configuration includes implanting the secondary stent to a position at which the primary stent overlaps the secondary stent over a distance greater than about one centimeter. 
     
     
         14 . The method of  claim 11  including a step of measuring a length along the axis of the shunt using a ruler measurement segment of the outer sheath, which is defined by radiopaque markers equally spaced along the axis, prior to the step of reconfiguring the duet stent deployment system from the predeployment configuration to the first deployment configuration. 
     
     
         15 . The method of  claim 11  including a step maintaining a first lock in a locked position and a second lock in a locked position during the maneuvering step;
 moving the first lock from the locked position to an unlocked position to enable movement of the duet stent deployment system from the predeployment configuration to the first deployment configuration; 
 maintaining the second lock in the locked position during the step of reconfiguring the duet stent deployment system from the predeployment configuration to the first deployment configuration; 
 maintaining the second lock in the locked position during the step of repositioning the duet stent deployment system; and 
 moving the second lock from the locked position to an unlocked position to enable movement of the duet stent deployment system from the first deployment configuration to the second deployment configuration. 
 
     
     
         16 . The method of  claim 11  wherein the combined primary stent and the secondary stent extend from the portal vein to the junction with the primary stent overlapping the secondary stent over a distance greater than about one centimeter. 
     
     
         17 . The method of  claim 11  including the steps of:
 deploying an anchoring mechanism; and 
 withdrawing the duet stent deployment system until the anchoring mechanism contacts the portal vein at an entrance to the shunt. 
 
     
     
         18 . The method of  claim 11  wherein the primary stent and the secondary stent are released prior to withdrawing the inner catheter and the outer sheath out through the vena cava. 
     
     
         19 . The method of  claim 18  wherein the combined primary stent and the secondary stent extend from the portal vein to the junction with the primary stent overlapping the secondary stent over a distance greater than about one centimeter. 
     
     
         20 . The method of  claim 19  including a step of measuring a distance along the axis from the junction to the shunt using a ruler measurement segment of the outer sheath, which is defined by radiopaque markers equally spaced along the axis, prior to the step of reconfiguring the duet stent deployment system from the first deployment configuration to the second deployment configuration;
 wherein the step of reconfiguring the duet stent deployment system from the first deployment configuration to the second deployment configuration includes implanting the secondary stent to a position at which the primary stent overlaps the secondary stent over a distance greater than about one centimeter; 
 measuring a length along the axis of the shunt using a ruler measurement segment of the outer sheath, which is defined by radiopaque markers equally spaced along the axis, prior to the step of reconfiguring the duet stent deployment system from the predeployment configuration to the first deployment configuration; 
 maintaining a first lock in a locked position and a second lock in a locked position during the maneuvering step; 
 moving the first lock from the locked position to an unlocked position to enable movement of the duet stent deployment system from the predeployment configuration to the first deployment configuration; 
 maintaining the second lock in the locked position during the step of reconfiguring the duet stent deployment system from the predeployment configuration to the first deployment configuration; 
 maintaining the second lock in the locked position during the step of repositioning the duet stent deployment system; and 
 moving the second lock from the locked position to an unlocked position to enable movement of the duet stent deployment system from the first deployment configuration to the second deployment configuration.