Coaxial balloon catheter

A balloon dilatation catheter comprising:

• an elongate, flexible catheter shaft including a two tube, two lumen configuration, the shaft having a proximal region, a proximal end and a distal end, wherein the shaft is formed from an inner tube defining a guidewire lumen therethrough, and a surrounding outer tube coaxial with the inner tube and defining an annular inflation lumen therebetween, the inner tube being of smaller diameter than the outer tube;
• an inflatable dilatation balloon having a proximal end and a distal end, the proximal end of the balloon being attached to a first distal region of the outer tube, the distal end of the balloon being attached to a second distal region of the outer tube at a distal connection;
• means for communicating the annular inflation lumen with the interior of the balloon to facilitate inflation and deflation of the balloon, the inflation lumen comprising the sole lumen in communication with the interior of the balloon;
• and
• the outer tube being attached to the inner tube at a location between the means for communicating and the distal end region of the inner tube.

A method of manufacturing a coaxial balloon catheter, comprising the steps of:

• forming at least one aperture on an elongated outer body to serve as an inflation port;
• inserting the elongated inner body coaxially within an elongated outer body;
• attaching a distal end of a balloon adjacent to a distal region of the elongated outer body;
• attaching the distal region of the elongated outer body to an outer portion of the elongated inner body;
• and
• attaching a proximal end of the balloon on a portion of the elongated outer body, wherein the balloon covers the at least one aperture.