![]() This actually has a theoretical justification: when the active electrode is inserted in homogeneous tissue and is assumed to be much smaller than the dispersive electrode, the area of the tissue around the active electrode can be increased without significantly changing baseline impedance, which in practical terms means that the RF power absorbed around the active electrode remains unchanged. All of these can be considered limited-domain models since they do not include the entire electrical circuit from the active electrode to the dispersive through the thorax tissues (see Figure 1(A)).Īlthough limited-domain models may be appropriate to study temperature distributions around the active electrode, they implicitly assume that all the power delivered by the RF generator (P 0 = V 0 × I 0 in Figure 1(B)) is absorbed by the volume around the active electrode (i.e., across the impedance Z MOD in Figure 1(B)). This dimension can range between a distance of from 12 to 75 mm around the active electrode (12 mm, 16 mm, 19 mm, 25 mm, 30 mm, 40 mm, 44 mm, 75 mm ). As almost all the models simplify reality by including only a relatively small region around the active electrode, the computational domain includes a zone of cardiac tissue and blood whose size depends on preventing the boundary conditions from affecting the results. ![]() Computer modeling has been broadly used to study specific issues associated with RFCA. Current density is especially high around the active electrode (due to its small size) and creates a thermal lesion exclusively in the target zone. During RFCA, electrical current flows between an active electrode (placed on the target site) and a dispersive electrode on the patient’s back. Radiofrequency (RF) cardiac ablation (RFCA) is a minimally invasive procedure aimed at treating certain types of arrhythmia.
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