RADIOFREQUENCY HEATED BIPOLAR ENERGY IN A RTERIES - EXPERIMENTAL RESULTS WITH A NEW CATHETER

Purpose: To evaluate the effects of radiofrequency heated bipolar prob es on the human arterial wall. Methods: Under standardised conditions, lesions were set on the inner layer of a piece of human cadaver arter ial wall, using a radiofrequency-heated bipolar catheter. These lesion s were measured and described both macroscopically and microscopically . Lesion size, applied energy levels and application conditions were c orrelated. Results: The size of a lesion depended significantly on the size of the catheter, angle and pressure of catheter application (p < 0.05) and length of impulse (p = 0.002). There was no influence from the energy level employed. It proved impossible to treat calcified pla ques. The depth of a lesion depended on the angle of catheter applicat ion only No perforations were seen. Conclusions: Radiofrequency-heated bipolar catheters ablate the tissue of the arterial wall. Increasing tissue resistance resulting from higher energy levels prevents perfora tion in the experimental set-up. Calcified plaques cannot be treated b y this method.