CATHETER AND METHOD FOR IMPROVED ABLATION

摘要

An ablation electrode is mounted on the distal end of a catheter with a first portion inside and a second portion outside the catheter. The second portion is adapted to have a surface that makes maximum contact with a tissue to be ablated, leaving a minimum area not covered by the tissue and potentially exposed to blood. The first portion is adapted to provide an extended surface area for efficient exchange of heat with a coolant flowing inside the catheter. Outlets provided near the area not covered by the tissue in the second portion prevents blood from getting close to or come directly in contact with the area, thereby greatly reducing formation of dangerous blood clots. The minimizing of an electrical circuit through blood greatly reduces wasted power into the electrode so that the efficiently cooled electrode is not burdened. The catheter preferably has multiple electrodes with similar features.

主权项

1. A catheter, comprising:
an elongated housing defining an axis and having a proximal end and a distal end; a first electrode body disposed at the distal end with a first portion enclosed within the elongated housing and a second portion exposed to outside of the catheter; a fluid supply port near the proximal end for supplying a coolant into the elongated housing; said first portion being of a shape having a surface area substantially larger than that of said second portion and being in fluid communication with the coolant for exchanging heat therewith; said second portion being of a shape having a protruding surface that when disposed to ablate a biological tissue is substantially covered by and in contact with the biological tissue while leaving a minimum surface area not in contact with and uncovered by the biological tissue; and an electrical conductor inside the elongated housing coupling the first electrode to a power supply at the distal end during an ablation operation.