Patent ID: 7806872

Claim:
An injection catheter comprising: a catheter body comprising a flexible tubing having proximal and distal ends and at least one lumen extending therethrough; a tip section comprising a flexible tubing having proximal and distal ends, wherein the proximal end of the tip section is mounted at the distal end of the catheter body, the tip section having a first needle passage extending therethrough, wherein the first needle passage has a proximal region having a proximal diameter and a distal region having a distal diameter less than the proximal diameter; a needle control handle at the proximal end of the catheter body; a tip electrode mounted on the distal end of the tip section and comprising a second needle passage; an injection needle extending through the catheter body, tip section, tip electrode and needle control handle and having a proximal end within the needle control handle and a distal end within the second needle passage in the tip electrode, wherein the injection needle is longitudinally slidable within the catheter body, tip section and tip electrode so that its distal end can extend beyond a distal end of the tip electrode; and a needle stop mounted on a portion of the injection needle that is positioned within the proximal region of the first needle passage, the needle stop having a distal end that is sized to prevent the portion of the injection needle on which the needle stop is mounted from passing into the distal region of the first needle passage; whereby the needle stop limits the distance that the injection needle can be extended beyond the distal end of the catheter body, and wherein the injection needle extends through a protective tube providing a fluid-tight seal surrounding the distal end of the injection needle.