Balloon catheter with adjustable sheath

Abstract

An intravascular balloon catheter device for treating various size stenosed regions within a blood vessel is provided. A clamp located within a body of a handle assembly is movable between a clamped and unclamped position by way of a button. When clamped, an outer member is secured relative to a sheath to as to expose a portion of a balloon located on a distal end of the outer member. The portion of the balloon remaining within the sheath is restricted from inflation beyond the sheath.

What is claimed is: 
     
         1 . A balloon catheter assembly comprising:
 an inner member;   an outer member disposed about the inner member;   a balloon located at a distal portion of said outer member, said balloon having a first end and a second end, wherein the first end of the balloon is connected to the outer member and the second end of the balloon is connected to the inner member;   a sheath disposed about the outer member and configured for movement relative to the balloon, wherein the sheath is configured to prevent a retained portion of the balloon from expanding beyond the sheath; and   an adjustment structure for securing the sheath at a desired position relative to the balloon to selectively expose an extending portion of the balloon for inflation such that the retained portion remains within the sheath.   
     
     
         2 . The balloon catheter assembly of  claim 1  further comprising:
 a housing for the adjustment structure, wherein said sheath is connected to said housing, and wherein said outer member extends through said housing. 
 
     
     
         3 . The balloon catheter assembly of  claim 2  further comprising:
 a first actuator arm; and 
 a second actuator arm, wherein said first actuator arm and said second actuator arm form at least a portion of said adjustment structure, and wherein said first actuator arm and said second actuator arm are supported within the housing and are selectively movable into engagement with the outer member. 
 
     
     
         4 . The balloon catheter assembly of  claim 3  further comprising:
 first and second actuator arm supports provided at said housing, wherein the first and second actuator arms are respectively supported on the first and second actuator arm supports; and 
 first and second engagement pads located at said first and second actuator arms, respectively, wherein said first and second engagement pads are selectively movable into engagement with the outer member. 
 
     
     
         5 . The balloon catheter assembly of  claim 3  further comprising:
 first and second springs supported at the housing and configured to bias said first and second actuator arms, respectively, into engagement with the outer member. 
 
     
     
         6 . The balloon catheter assembly of  claim 3  further comprising:
 first and second push buttons that are operable to move the first and second actuator arms, respectively, out of engagement with the outer member. 
 
     
     
         7 . The balloon catheter assembly of  claim 1  further comprising:
 a drug coating provided at an outer surface of the balloon, and 
 a tip member located at a distal end of the balloon and configured to provide a watertight engagement between the sheath and the tip member when the tip member is positioned adjacent to a distal end of the sheath. 
 
     
     
         8 . The balloon catheter assembly of  claim 1  further comprising:
 a collar provided about an end of the sheath and configured to provide additional strength to the sheath. 
 
     
     
         9 . The balloon catheter assembly of  claim 1  further comprising:
 a plurality of spaced indentations provided at said outer member, wherein each of said plurality of spaced indentations is configured for selective engagement with the adjustment structure. 
 
     
     
         10 . The balloon catheter assembly of  claim 1  further comprising:
 a plurality of spaced annular protrusions provided at said outer member, wherein each of said plurality of spaced annular protrusions is configured for selective engagement with the adjustment structure. 
 
     
     
         11 . The balloon catheter assembly defined in  claim 1  further comprising:
 a series of radiopaque marker bands located at select intervals on the inner member; and 
 a series of radiopaque marker bands located at select intervals on the sheath. 
 
     
     
         12 . An intravascular catheter device for treating various length zones of attention, said device comprising:
 a handle assembly;   a sheath extending from said handle assembly;   an outer member extending through said handle assembly;   a balloon located at a distal portion of said outer member;   an inner member extending within said outer member; and   a clamp located at said handle assembly, wherein said clamp is configured for movement between a clamped position where a portion of said clamp engages the outer member to prevent movement of the outer member and an unclamped position where the clamp disengages the outer member to permit axial movement of the outer member and inner member through the handle assembly so as to expose a variable length portion of said balloon for inflation.   
     
     
         13 . The intravascular catheter device of  claim 12  further comprising:
 a housing for the clamp; and 
 a first and second actuator arm located within the housing and forming at least a portion of said clamp. 
 
     
     
         14 . The intravascular catheter device of  claim 13  further comprising
 first and second actuator arm supports provided at said housing, wherein the first and second actuator arms are respectively supported on the first and second actuator arm supports; and 
 first and second engagement pads located at distal ends of said first and second actuator arms, respectively, wherein said first and second engagement pads are configured to contact said outer member when the clamp is placed in the clamped position. 
 
     
     
         15 . The intravascular catheter device of  claim 13  further comprising:
 first and second actuator arm supports provided at said housing, wherein the first and second actuator arms are respectively supported on the first and second actuator arm supports; and 
 a plurality of spaced indentations or protrusions provided at said outer member, wherein said plurality of spaced indentations or protrusions are configured to be engaged by the first and second actuator arms when the clamp is placed in the clamped position. 
 
     
     
         16 . A method for treating various length zones of attention comprising the steps of:
 providing an intravascular catheter device comprising an inner member, an outer member disposed about the inner member, a balloon located at a distal portion of said outer member, a sheath, and a clamp;   sheathing the balloon;   directing the sheathed balloon to a zone of attention within a person's vascular system;   placing the clamp in a disengaged position;   moving the sheath relative to the balloon while the clamp is in the disengaged position to expose a distal portion of the balloon for inflation and keeping a proximal portion of the balloon sheathed;   placing the clamp in an engaged position to secure the sheath relative to the balloon; and   inflating the balloon such that the distal portion of the balloon expands to a diameter larger than an outer diameter of the sheath and the proximal portion inflates to contact an inner surface of the sheath.   
     
     
         17 . The method of  claim 16  wherein:
 the sheath is secured relative to the balloon such that a length of the distal portion of the balloon exposed for inflation is sized to match a length of the zone of attention. 
 
     
     
         18 . The method of  claim 17  further comprising the steps of:
 providing a series of radiopaque markers located at select intervals on the inner member; and 
 providing a sheath radiopaque marker at a distal end of the sheath, wherein the location of the sheath relative to the balloon is observed by the location of the sheath radiopaque marker relative to one or more of the series of radiopaque markers. 
 
     
     
         19 . The method of  claim 16  wherein:
 movement of the clamp between the engaged and disengaged positions is accomplished by depressing or releasing one or more buttons at a housing for said clamp; and 
 depression of said one or more buttons is configured to move one or more actuator arms supported within said housing into or out of contact with said outer member. 
 
     
     
         20 . The method of  claim 19  wherein:
 the step of moving the sheath relative to the balloon is accomplished by axially extending or retracting the outer member and the inner member through the housing.