| 摘要 |
<p>A catheter (14) for use in an electro-physiological procedure to ablate a site includes a metallic tip (30) having a first work function and energized by a source of RF energy. The RF energy return path is through a relatively large plate (34) of a metallic material having a second work function and disposed at a second location removed from the ablation site. The difference in work functions of the tip and the plate, operating in the presence of an electrolyte represented by intermediate tissue, produces an exchange of electrical charges through chemical reaction to create a galvanic cell. By loading the galvanic cell with a shunt resistor, it becomes a current source providing a current signal having a peak value representative of occurence of tissue damage. This representation is used to regulate the RF energy applied to the ablation site.</p> |
