Intravascular catheter

Claim 1

A coaxial dilation catheter comprising: an outer tubular member having a proximal and distal end; an inner tubular member concentrically disposed within said outer tubular member so as to define an inflation lumen therebetween, said inner tubular member having a proximal end and a distal end; an extension tubular member, said extension member having a proximal end and a distal end wherein said proximal end of said extension tubular member is placed around said distal end of said inner tubular member in a transition area so that said inner tubular member defines a guide wire lumen proximal of said transition area and said extension tubular member defines a guide wire lumen distal of said transition area; an inflatable balloon having a proximal and distal waist, said proximal waist located at least partially within said transition area, said inflatable balloon surrounding said extension tubular member and extending from said distal end of said outer tubular member, said distal end of said outer tubular member terminating in said transition area, to said distal end of said extension tubular member wherein said proximal waist of said balloon surrounds said distal end of said outer tubular member whereby an inflation lumen extending through said transition area is formed by inserting at least one mandrel into the inflation lumen, and securing said proximal waist to said outer tubular member and said outer tubular member to said distal end of said inner tubular member and said proximal end of said tubular extension member by heat bonding in said transition area.

Claim 3

A method of making a coaxial dilation catheter comprising the steps of: providing an outer tubular member having a proximal and distal end, said distal end terminating in a transition area; providing an inner tubular member having a proximal and distal end, said distal end also terminating in said transition area; providing an extension member having a proximal and distal end, said proximal end terminating in said transition area; placing said proximal end of said extension tube around said distal end of said inner tube in said transition area wherein said inner tube defines a guide wire lumen proximal of said transition area while said extension tube defines a guide wire lumen distal of said transition area; concentrically disposing said inner tube and said extension tube within said outer tubular member so as to define an inflation lumen therebetween wherein said distal end of said outer tube substantially coincides with said transition area; surrounding said extension member with an inflatable balloon having a proximal and distal waist wherein said balloon extends from said distal end of said outer member in said transition area to the distal tip of said catheter; inserting at least one mandrel in said inflation lumen within said transition area; applying a heat weld to said proximal waist of said balloon to bond said proximal waist to said outer tube proximate its distal end and to bond said outer tube within said transition area around said mandrel to said proximal end of said extension member and said distal end of said inner tube; removing said at least one mandrel from said inflation lumen to define at least one aperture; and bonding said distal waist to the distal end of said extension tube.

Claim 4

A method of making a coaxial dilation catheter comprising the steps of: providing an outer tubular member having a proximal and distal end, said distal end terminating in a transition area; providing an inner tubular member having a proximal and distal end, said distal end also terminating in said transition area; providing an extension member having a proximal and distal end, said proximal end terminating in said transition area; placing said proximal end of said extension tube around said distal end of said inner tube in said transition area wherein said inner tube defines a guide wire lumen proximal of said transition area while said extension tube defines a guide wire lumen distal of said transition area; concentrically disposing said inner tube and said extension tube within said outer tubular member so as to define an inflation lumen therebetween wherein said distal end of said outer tube substantially coincides with said transition area; surrounding said extension member with an inflatable balloon having a proximal and distal waist wherein said balloon extends from said distal end of said outer member in said transition area to the distal tip of said catheter; inserting at least one mandrel in said inflation lumen within said transition area; applying a heat weld to said proximal waist of said balloon to bond said proximal waist to said outer tube proximate its distal end and to bond said outer tube within said transition area around said mandrel to said proximal end of said extension member and said distal end of said inner tube; removing said at least one mandrel from said inflation lumen to define at least one aperture; and bonding said distal waist to the distal end of said extension tube.