Balloon catheter having dual markers and method

Claim 2

An intravascular balloon catheter for treating a portion of the body of a patient, comprising: a flexible catheter shaft, at least a distal portion of the catheter shaft having an inner shaft member coaxially surrounded by an outer shaft member, an inflation lumen being defined by an annular space between said inner and outer shaft members; a flexible balloon disposed near a distal end of the catheter shaft, the balloon having a working portion with a constant cross-sectional area, a proximal end of the balloon being sealed to the outer shaft member, and a distal end of the balloon being sealed to the inner shaft member, whereby the inflation lumen is in fluid communication with the interior of the balloon; and first and second radiopaque markers disposed within the interior of the balloon, the first marker being affixed to the inner shaft member, and the second marker being affixed to the outer shaft member, said first and second markers being positioned at a distal and proximal end of the balloon working portion, respectively, whereby the first and second markers indicate under fluoroscopy the position of the balloon working portion within the body of the patient.

Claim 3

The intravascular balloon catheter as set forth in claim 1, wherein the balloon working portion has a cylindrical shape.

Claim 4

The intravascular balloon catheter as set forth in claim 2, the balloon further comprising a proximal and distal frusto-conical tapering segment, and proximal and distal legs being sealed to the outer and inner shaft members, respectively, wherein each of the first and second markers are longitudinally positioned at a transition between the cylindrical working portion and the distal and proximal tapering segments, respectively.

Claim 5

The intravascular balloon catheter as set forth in claim 1, wherein the balloon is formed of at least two layers of different materials.

Claim 6

The intravascular balloon catheter as set forth in claim 1, further comprising a flexible fixed wire affixed to the inner shaft member and extending distally beyond the distal end of the inner shaft member.

Claim 7

The intravascular balloon catheter as set forth in claim 1, wherein the balloon is formed of a substantially inelastic material.

Claim 8

The intravascular balloon catheter as set forth in claim 1, wherein the inner shaft member defines a guidewire lumen adapted to slidingly receive a guidewire extending from a proximal guidewire port that is proximal of the balloon to a distal guidewire port that is distal to the balloon.

Claim 9

The intravascular balloon catheter as set forth in claim 7, wherein the proximal guidewire port is disposed between a proximal end of the catheter shaft and the balloon, thereby enabling a guidewire to traverse a path from the distal guidewire port through the guidewire lumen defined by the inner shaft member, through the proximal guidewire port, and extend proximally along the exterior of a proximal portion of the catheter shaft in a rapid exchange configuration.

Claim 10

The intravascular balloon catheter as set forth in claim 7, wherein said catheter shaft further comprises a proximal shaft portion defining a proximal inflation lumen and a proximal guidewire lumen, the proximal inflation lumen communicating with an inflation lumen defined by an annular space between the outer and inner shaft members, and the proximal guidewire lumen extending parallel to the proximal inflation lumen and communicating with the guidewire lumen.

Claim 11

The intravascular balloon catheter as set forth in claim 7, wherein said inner shaft member is formed of at least two layers of different materials, the innermost layer defining the guidewire lumen and being more lubricious to facilitate movement of a guidewire within the guidewire lumen.

Claim 12

The intravascular balloon catheter as set forth in claim 1, wherein inner and outer shaft members are each formed of plastic, and the first and second markers are formed of metal.

Claim 13

An intravascular balloon catheter for treating a portion of the body of a patient, comprising: a flexible catheter shaft. at least a distal portion of the catheter shaft having an inner shaft member coaxially surrounded by an outer shaft member, an inflation lumen being defined by an annular space between said inner and outer shaft members; a flexible balloon disposed near a distal end of the catheter shaft, a proximal end of the balloon being sealed to the outer shaft member, and a distal end of the balloon being sealed to the inner shaft member, whereby the inflation lumen is in fluid communication with the interior of the balloon; and first and second radiopaque markers disposed within the interior of the balloon, the first marker being affixed to the inner shaft member, and the second marker being affixed to the outer shaft member, whereby the first and second markers indicate under fluoroscopy the position of the balloon within the body of the patient, wherein the second marker is formed by a plastic ring containing a radiopaque agent and affixed to a distal end of said outer shaft member.

Claim 14

An intravascular balloon catheter for treating a portion of the body of a patient, comprising: a flexible catheter shaft. at least a distal portion of the catheter shaft having an inner shaft member coaxially surrounded by an outer shaft member, an inflation lumen being defined by an annular space between said inner and outer shaft members; a flexible balloon disposed near a distal end of the catheter shaft, a proximal end of the balloon being sealed to the outer shaft member, and a distal end of the balloon being sealed to the inner shaft member, whereby the inflation lumen is in fluid communication with the interior of the balloon; and first and second radiopaque markers disposed within the interior of the balloon, the first marker being affixed to the inner shaft member, and the second marker being affixed to the outer shaft member, whereby the first and second markers indicate under fluoroscopy the position of the balloon within the body of the patient, wherein the second marker is formed by a plastic ring containing a radiopaque agent and affixed to a distal end of said outer shaft member.

Claim 15

The intravascular balloon catheter as set forth in claim 12, wherein a percentage concentration of said radiopaque agent is predetermined, such that said first and second markers have equal fluoroscopic brightness.

Claim 16

The intravascular balloon catheter as set forth in claim 12, wherein the second marker has the same outer diameter as said outer shaft member.

Claim 17

An intravascular balloon catheter, comprising: a first tube of flexible plastic defining a guidewire lumen, said first tube being formed of an outer plastic layer and an inner plastic layer, the plastic materials of said outer and inner plastic layers being different and bonded to each other, said guidewire lumen being adapted to slidingly receive a guidewire, said inner plastic layer exhibiting a more lubricious surface than said outer plastic layer; a second flexible plastic tube surrounding said first tube and defining an inflation lumen between the outer surface of the first tube and the inner surface of the second tube; a flexible balloon having a distal end coupled to said first tube and a proximal end coupled to said second tube, such that the interior volume of the balloon is in fluid communication with said inflation lumen; and first and second radiopaque markers affixed to the first and second tube, respectively.

Claim 18

An intravascular balloon catheter, comprising: a first tube of flexible plastic defining a guidewire lumen, said first tube being formed of an outer plastic layer and an inner plastic layer, the plastic materials of said outer and inner plastic layers being different and bonded to each other, said guidewire lumen being adapted to slidingly receive a guidewire, said inner plastic layer exhibiting a more lubricious surface than said outer plastic layer; a second flexible plastic tube surrounding said first tube and defining an inflation lumen between the outer surface of the first tube and the inner surface of the second tube; a flexible balloon having a distal end coupled to said first tube and a proximal end coupled to said second tube, such that the interior volume of the balloon is in fluid communication with said inflation lumen; and first and second radiopaque markers affixed to the first and second tube, respectively.

Claim 19

The intravascular balloon catheter as set forth in claim 15, in which the material of the outer plastic layer has greater stiffness than the material of the inner plastic layer.

Claim 20

The intravascular balloon catheter as set forth in claim 15, in which the material of said outer plastic layer is selected from the group consisting of nylon, polyurethane, and polyester.

Claim 21

The intravascular balloon catheter as set forth in claim 15, wherein the balloon defines a working length, said first and second markers being positioned at a distal and proximal end of the working length, respectively.

Claim 22

The intravascular balloon catheter as set forth in claim 15, wherein the balloon is formed of a substantially inelastic material.

Claim 23

The intravascular balloon catheter as set forth in claim 15, further comprising a distal guidewire port that is distal to the balloon and a proximal guidewire port that is between the balloon and a proximal end of the second tube, thereby enabling a guidewire to traverse a path from the distal guidewire port through the guidewire lumen, through the proximal guidewire port, and extend proximally along the exterior of a proximal portion of the catheter shaft in a rapid exchange configuration.

Claim 24

The intravascular balloon catheter as set forth in claim 20, wherein the second marker has the same outer diameter as said second shaft member.

Claim 25

The intravascular balloon catheter as set forth in claim 15, wherein the second marker is formed by a plastic ring containing a radiopaque agent and affixed to a distal end of said second shaft member.

Claim 26

The intravascular balloon catheter as set forth in claim 15, wherein inner and outer shaft members are each formed of plastic, and the first and second markers are formed of metal.

Claim 27

An intravascular balloon catheter for expanding a stent within the body of a patient, comprising: a flexible catheter shaft, at least a distal portion of the catheter shaft having an inner shaft member coaxially surrounded by an outer shaft member; a flexible balloon disposed near a distal end of the catheter shaft, a proximal end of the balloon being sealed to the outer shaft member, and a distal end of the balloon being sealed to the inner shaft member; first and second radiopaque markers disposed within the interior of the balloon, the first marker being affixed to the inner shaft member, and the second marker being affixed to a distal end of the outer shaft member, an outer diameter of the second inner marker being larger than an outer diameter of the outer shaft member, thereby forming an annular shelf; a stent assembled in a crimped configuration around the balloon in an uninflated state, whereby the balloon is adapted to inflate and expand the stent within the desired site, said annular shelf engaging a proximal end of the stent to resist proximal motion of the stent relative to the catheter shaft as the balloon catheter is advanced within the body of the patient.

Claim 28

An intravascular balloon catheter for expanding a stent within the body of a patient, comprising: a flexible catheter shaft, at least a distal portion of the catheter shaft having an inner shaft member coaxially surrounded by an outer shaft member; a flexible balloon disposed near a distal end of the catheter shaft, a proximal end of the balloon being sealed to the outer shaft member, and a distal end of the balloon being sealed to the inner shaft member; first and second radiopaque markers disposed within the interior of the balloon, the first marker being affixed to the inner shaft member, and the second marker being affixed to a distal end of the outer shaft member, an outer diameter of the second inner marker being larger than an outer diameter of the outer shaft member, thereby forming an annular shelf; a stent assembled in a crimped configuration around the balloon in an uninflated state, whereby the balloon is adapted to inflate and expand the stent within the desired site, said annular shelf engaging a proximal end of the stent to resist proximal motion of the stent relative to the catheter shaft as the balloon catheter is advanced within the body of the patient.

Claim 29

The intravascular balloon catheter as set forth in claim 24, wherein the balloon defines a working length, said first and second markers being positioned at a distal and proximal end of the working length, respectively.

Claim 30

The intravascular balloon catheter as set forth in claim 24, wherein the inner shaft member defines a guidewire lumen adapted to slidingly receive a guidewire extending from a proximal guidewire port that is proximal of the balloon to a distal guidewire port that is distal to the balloon.

Claim 31

The intravascular balloon catheter as set forth in claim 26, wherein the proximal guidewire port is disposed between a proximal end of the catheter shaft and the balloon, thereby enabling a guidewire to traverse a path from the distal guidewire port through the guidewire lumen defined by the inner shaft member, through the proximal guidewire port, and extend proximally along the exterior of a proximal portion of the catheter shaft in a rapid exchange configuration.

Claim 34

The method of claim 28, further comprising the additional step of sealing the proximal ends of the inner and outer shaft members, to resist relative movement thereof.

Claim 35

The method of claim 28, further comprising the additional step of forming the proximal marker of a plastic formulation having a radiopaque agent.

Claim 36

The method of claim 28, wherein said step of providing the inner shaft member further comprises coextruding the inner shaft member into a tube defining a lubricious guidewire lumen.