Conduits for use in placing a target vessel in fluid communication with a source of blood

Abstract

Methods and devices for placing a target vessel in fluid communication with a source of blood and a target vessel. A conduit includes first portion adapted to be placed in fluid communication with a source of blood, such as a heart chamber, and a second portion adapted to be placed in fluid communication with a target vessel having a lumen, such as coronary artery. The first and second conduit portions are transverse to each other such that the conduit is generally T-shaped. The conduit lies on an exterior of the heart between the blood source and the target vessel and is configured to deliver blood in multiple directions into the lumen of the target vessel. For example, in an occluded coronary artery, blood flows both toward and away from the occlusion. The conduit may be flexible, rigid, collapsible or non-collapsible, and may be formed of synthetic vascular graft material, tissue, or a combination of the two. A conduit delivery device is disclosed for deploying the conduit in a target vessel and perfusing the vessel during such deployment.

What is claimed is:  
     
         1 . A method for delivering blood from a heart chamber containing blood to a target vessel of a patient's vascular system, the method comprising steps of: 
 (a) placing a conduit having a lumen in fluid communication with a heart chamber containing blood;    (b) placing the conduit in fluid communication with the lumen of a target vessel and securing the conduit to the target vessel;    (c) delivering blood from the heart chamber into the conduit during at least one phase of the heart cycle; and    (d) permitting the blood to flow from the conduit into the lumen of the target vessel in more than one direction.    
     
     
         2 . The method of  claim 1 , wherein a portion of the conduit extending between the heart chamber and the target vessel is disposed on an exterior of the patient's heart.  
     
     
         3 . The method of  claim 1 , wherein the conduit is generally T-shaped and includes a first portion having one free end and a second portion having two free ends, and step (a) is performed by placing the first conduit portion through the myocardium and at least partially within the heart chamber while step (b) is performed by placing the second conduit portion at least partially within the lumen of the target vessel.  
     
     
         4 . The method of  claim 3 , wherein the first conduit portion is formed of a material having sufficient rigidity to avoid collapsing during myocardial contraction when placed according to step (a).  
     
     
         5 . The method of  claim 4 , wherein step (a) is performed prior to step (b), and step (b) is performed by securing the second conduit portion to the target vessel via a substantially suture-free attachment.  
     
     
         6 . The method of  claim 4 , wherein the second conduit portion is passed through a wall of the target vessel and placed at least partially within the lumen of the target vessel without collapsing the second leg of the conduit, and blood flows within the lumen of the target vessel in two opposite directions.  
     
     
         7 . The method of  claim 4 , wherein the target vessel has a lumen that is at least partially obstructed by an occlusion, and the plurality of directions include toward and away from the occlusion.  
     
     
         8 . A method for delivering blood from a heart chamber containing blood to a target vessel of a patient's vascular system, the method comprising steps of: 
 (a) placing a conduit having a lumen in fluid communication with a heart chamber containing blood;    (b) placing the conduit in fluid communication with the lumen of a target vessel and securing the conduit to the target vessel;    (c) delivering blood from the heart chamber into the conduit during at least one phase of the heart cycle; and    (d) permitting blood to flow out of the conduit unrestricted in more than one direction in the lumen of the target vessel.    
     
     
         9 . The method of  claim 8 , wherein the conduit is disposed along the exterior of the heart.  
     
     
         10 . The method of  claim 8 , wherein the heart chamber contains oxygenated blood and the target vessel is a coronary artery.  
     
     
         11 . The method of  claim 10 , wherein the heart chamber is the left ventricle, and blood flows from the heart chamber into the conduit and into the target vessel during both phases of the heart cycle.  
     
     
         12 . A method for placing a target vessel of a patient's coronary vascular system in fluid communication with a heart chamber containing blood, the method comprising steps of: 
 (a) providing a conduit including first and second portions that are disposed transverse to each other and have lumens in fluid communication, the first conduit portion including at least one inlet and the second conduit portion including at least one outlet;    (b) placing the inlet of the first conduit portion in fluid communication with a heart chamber containing blood to allow blood to enter the lumen of the first conduit portion;    (c) positioning the outlet of the second conduit portion in fluid communication with the lumen of a target vessel at a selected location in the target vessel to allow blood to flow into the lumen of the target vessel from the second conduit portion; and    (d) securing the second conduit portion to the target vessel at the selected location while substantially not moving the second conduit portion along a longitudinal axis of the target vessel.    
     
     
         13 . The method of  claim 12 , wherein the conduit is disposed along an exterior of the patient's heart.  
     
     
         14 . The method of  claim 12 , wherein the second conduit portion of the conduit is secured to the target vessel via a substantially suture-free, end-to-side attachment.  
     
     
         15 . A method for deploying a conduit to deliver blood from a heart chamber to a target vessel of a patient's coronary vascular system, the method comprising steps of: 
 (a) providing a conduit including first and second portions each of which has a lumen, wherein the first and second conduit portions are disposed transverse to each other with the lumens in fluid communication and the second conduit portion is at least partially collapsible;    (b) placing the lumen of the first conduit portion in fluid communication with a heart chamber containing blood;    (c) at least partially collapsing the second conduit portion and positioning the second conduit portion at least partially within the lumen of a target vessel at a selected location in the target vessel; and    (d) expanding the second conduit portion within the lumen of the target vessel at the selected location to secure the second conduit portion to the target vessel in fluid communication therewith.    
     
     
         16 . The method of  claim 15 , wherein the target vessel is at least partially obstructed by an occlusion and the conduit is disposed along the exterior of the heart adjacent the myocardium, and the second conduit portion has multiple outlets that direct blood toward and away from the occlusion.  
     
     
         17 . The method of  claim 15 , wherein step (c) is performed by making an incision in a wall of the target vessel and inserting the collapsed second conduit portion into the lumen of the target vessel, and step (d) is performed by removing a restraining element that holds the second conduit portion in a collapsed state.  
     
     
         18 . A method for delivering blood from a heart chamber containing blood to a target vessel of a patient's vascular system by placing conduit in the myocardium, the method comprising steps of: 
 (a) determining a thickness of the patient's myocardium adjacent a heart chamber containing blood;    (b) placing a conduit having a lumen in the myocardium with the lumen of the conduit in fluid communication with the heart chamber containing blood;    (c) placing the conduit in fluid communication with the lumen of a target vessel and securing the conduit to the target vessel; and    (d) delivering blood from the heart chamber into the conduit and allowing blood to exit the conduit and enter the target vessel in more than one direction.    
     
     
         19 . A device for placing a target vessel of a patient's vascular system in fluid communication with a heart chamber containing blood, the device comprising: 
 a conduit including first and second portions, wherein the first and second conduit portions each have an axis and a lumen through which blood may flow, the axes of the first and second conduit portions being transverse to each other;    wherein the first conduit portion is configured to be placed in fluid communication with a heart chamber containing blood and includes at least one inlet configured to be at least partially positioned in myocardial tissue without collapsing during myocardial contraction;    wherein the second conduit portion is configured to be at least partially positioned within the target vessel and includes at least one outlet adapted to deliver blood to the lumen of the target vessel; and    wherein the inlet of the first conduit portion is more rigid than the outlet of the second conduit portion.    
     
     
         20 . The device of  claim 19 , wherein the first conduit portion is at least partially formed of a rigid, non-compliant material, and the second conduit portion is at least partially formed of a compliant material.  
     
     
         21 . The device of  claim 20 , wherein the first conduit portion comprises a rigid, metallic member and the second conduit portion comprises a graft vessel.  
     
     
         22 . The device of  claim 21 , wherein the graft vessel is joined to the metallic member and comprises a synthetic vascular graft material.  
     
     
         23 . The device of  claim 19 , further comprising a reinforcing member that extends at least partially along the conduit and provides at least the second conduit portion and the outlet with a desired amount of rigidity.  
     
     
         24 . The device of  claim 23 , wherein the reinforcing member comprises at least one wire wrapped around the first and second conduit portions.  
     
     
         25 . The device of  claim 24 , wherein the wire is helically wrapped and has a smaller pitch length on the second conduit portion than the first conduit portion.  
     
     
         26 . The device of  claim 23 , wherein the reinforcing member comprises at least one sleeve coupled to the second conduit portion.  
     
     
         27 . The device of  claim 26 , wherein the sleeve is formed of a rigid material selected from the group consisting of PEEK, polyurethane, polyethylene, polypropylene, stainless steel, titanium, tantalum and a nickel-titanium alloy, and the sleeve is located adjacent the outlet.  
     
     
         28 . The device of  claim 19 , wherein the axes of the first and second conduit portions are generally perpendicular such that the conduit is substantially T-shaped, and the first conduit portion corresponds to a first leg of the T having one free end while the second conduit portion corresponds to a second leg of the T having two free ends.  
     
     
         29 . The device of  claim 28 , wherein the second conduit portion is configured such that the outlet may be disposed and secured within the lumen of the target vessel without contacting the entire circumference of the inner vessel wall.  
     
     
         30 . The device of  claim 29 , wherein the second conduit portion is generally semicircular in cross-section so as to leave the inner wall of the target vessel substantially uncovered.  
     
     
         31 . The device of  claim 28 , wherein at least one of the two free ends of the second conduit portion is expandable in at least one of an axial direction and a radial direction.  
     
     
         32 . The device of  claim 28 , wherein at least one of the two free ends has a beveled tip for introduction into the target vessel.  
     
     
         33 . The device of  claim 19 , wherein the first and second conduit portions meet at a junction that is less rigid than the first or second conduit portion.  
     
     
         34 . A device for placing a target vessel of a patient's vascular system in fluid communication with a heart chamber containing blood, the device comprising: 
 a conduit having first and second portions each having a lumen, wherein the first and second conduit portions are disposed transverse to each other with the lumens in fluid communication;    wherein the first conduit portion has a longitudinal axis and is sized and configured to be placed in fluid communication with a heart chamber containing blood;    wherein the second conduit portion has a longitudinal axis and is sized and configured to be placed at least partially within a target vessel in a patient's vascular system to deliver blood to the target vessel, the second conduit portion including first and second ends adapted to be positioned in the target vessel; and    wherein the longitudinal axis of the first conduit portion crosses the longitudinal axis of the second conduit portion at a location that is spaced different distances from the first and second ends of the second conduit portion.    
     
     
         35 . The method of  claim 34 , wherein the second conduit portion is provided with a selected amount of rigidity so as to be self-supporting yet compliant when in an expanded orientation, while being at least partially deformable to a collapsed orientation for introduction into the lumen of the target vessel.  
     
     
         36 . The device of  claim 35 , wherein the first and second conduit portions meet at a junction, the first conduit portion being more rigid than the second conduit portion, and the second portion of the conduit being more rigid than the junction.  
     
     
         37 . The device of  claim 34 , wherein the first conduit portion comprises a rigid member configured to be positioned in myocardial tissue, and the second conduit portion comprises a bifurcated graft vessel coupled to the rigid member.  
     
     
         38 . The device of  claim 37 , wherein the graft vessel comprises synthetic vascular graft material selected from the group consisting of expanded polytetrafluoroethylene, polyethylene terephthalate, polyurethane and silicone.  
     
     
         39 . The device of  claim 34 , wherein the second conduit portion includes a reinforcing member disposed adjacent one of the first and second free ends.  
     
     
         40 . The device of  claim 34 , wherein the second conduit portion has first and second blood outlets.  
     
     
         41 . The device of  claim 40 , wherein the longitudinal axis of the first conduit portion crosses the longitudinal axis of the second conduit portion at a location that is spaced different distances from the first and second blood outlets of the second conduit portion.  
     
     
         42 . The device of  claim 34 , wherein the conduit is generally T-shaped and the first conduit portion corresponds to one leg of the T having one end while the second conduit portion corresponds to another leg of the T having two ends, and wherein the two ends of the other leg of the T define the first and second blood outlets and are spaced different distances from the one leg of the T.  
     
     
         43 . A device for placing a target vessel of a patient's vascular system in fluid communication with a heart chamber containing blood by forming a blood flow path between the target vessel and the heart chamber, the device comprising: 
 a conduit having first and second portions each of which has an axis, the axes of the first and second conduit portions being transverse to each other;    wherein the first conduit portion has a free end and is configured to be placed in fluid communication with a heart chamber containing blood, and the second conduit portion has two free ends that are sized and configured to be positioned at least partially within the lumen of a target vessel in the patient's vascular system; and    wherein the conduit is formed at least in part of a molded thermoset material having a predetermined amount of flexibility to permit the second portion of the conduit to be flexed for placement within the lumen of a target vessel.    
     
     
         44 . The device of  claim 43 , wherein the first conduit includes a member configured to be placed in myocardial tissue without collapsing during myocardial contraction.  
     
     
         45 . The device of  claim 44 , wherein the conduit is generally T-shaped and the first conduit portion corresponds to one leg of the T having one free end while the second conduit portion corresponds to another leg of the T having two free ends, and wherein the two free ends of the other leg of the T define first and second outlets adapted to be placed in fluid communication with the lumen of the target vessel.  
     
     
         46 . The device of  claim 45 , wherein the second conduit portion conduit is configured such that the outlets may be disposed and secured within the lumen of the target vessel without the second conduit portion contacting the entire circumference of the inner vessel wall.  
     
     
         47 . The device of  claim 46 , wherein the second conduit is generally semicircular in cross-section so as to leave the inner wall of the target vessel substantially uncovered.  
     
     
         48 . The device of  claim 45 , wherein at least one of the two free ends of the other leg of the T is expandable in an axial direction as well as a radial direction.  
     
     
         49 . The device of  claim 45 , wherein at least one of the two free ends of the other leg of the T has a shaped tip for smooth introduction into the target vessel.  
     
     
         50 . The device of  claim 43 , wherein the first conduit portion has a length in the range of from about 30 mm to about 50 mm, while the second conduit portion has a length in the range of from about 3 mm to about 20 mm.  
     
     
         51 . A device for delivering a conduit configured to be placed in fluid communication with a target vessel and a source of blood, the device comprising: 
 a support shaft having a length;    a sheath having a length, a lumen, and a wall with at least one opening extending into the lumen;    wherein the support shaft is sized and configured to be at least partially positioned in the sheath lumen so as to contact the sheath wall and substantially block the opening by preventing communication with the sheath lumen via the opening; and    wherein the support shaft is movable within the sheath lumen to selectively block or unblock the opening in the sheath wall.    
     
     
         52 . The device of  claim 51 , wherein the support shaft is an obturator having a size that permits the obturator to slide within the sheath lumen, and the sheath wall includes a plurality of openings.  
     
     
         53 . The device of  claim 51 , wherein the sheath is sized and configured to be received in a portion of a conduit that is sized and configured to be received in a coronary vessel.  
     
     
         54 . In combination with a conduit for use in placing a target vessel in fluid communication with a source of blood, a delivery device for deploying the conduit, the combination comprising: 
 a conduit including first and second portions, wherein the first and second conduit portions each have an axis and a lumen through which blood may flow, the axes of the first and second conduit portions being transverse to each other;    wherein the first conduit portion includes at least one inlet configured to be placed in fluid communication with a heart chamber containing blood, and the second conduit portion includes at least one outlet configured to be at least partially positioned within the lumen of a target vessel to deliver blood to the target vessel;    a delivery device including a shaft with a lumen and at least one opening extending into the lumen, wherein the second conduit portion is mounted on the shaft;    wherein the shaft opening is movable into and out of alignment with the lumen of the first conduit portion; and    wherein the shaft opening is moved into alignment with the lumen of the first conduit portion to deliver blood from the first conduit portion to the shaft lumen.    
     
     
         55 . The combination of  claim 54 , wherein the shaft is rotatable within the second conduit portion, and the conduit is generally T-shaped.  
     
     
         56 . The combination of  claim 55 , wherein the hollow shaft is a sheath, and further comprising an obturator rotatably positioned in the sheath.