METHOD AND APPARATUS FOR DELIVERY AND DETECTION OF TRANSMURAL CARDIAC ABLATION LESIONS

摘要

During cardiac wall tissue ablation with an RF catheter, the observation of an 8 to 12 ohm drop in the tissue impedance is indicative of the production of a transmural lesion. Due to a magnetic catheter's ability to stay in the same position throughout the cardiac cycle and the consistency of forces applied throughout the cardiac cycle, the impedance measurement from the distal electrode of the magnetic catheter is uniquely useful in determining the achievement of a transmural lesion. The use of this impedance measurement during ablation with a magnetic catheter can thus be used as an indication of when the ablation has achieved a successful treatment endpoint. An RF generator's impedance measurement along with knowledge of the navigational state of a magnetic catheter can thus be used to control the delivery of energy for the purpose of delivering only as much RF energy as is necessary to achieve a clinically effective lesion and to stop RF energy delivery prior to the onset of an adverse event.