Using a specific PI controller tailored to different tissue and electrode conditions resulted in minimal changes to T(max) (<1.9°C) and lesion dimensions (<0.3 mm) compared to a standard controller.
Does tailoring the Kp and Ki values of a PI controller during RF cardiac ablation improve lesion dimensions and dynamic behavior compared to a standard PI controller in theoretical models?
Tailoring PI controller parameters for specific tissue and electrode conditions during RF ablation does not significantly alter lesion dimensions compared to a standard controller in theoretical models.
PURPOSE: To assess whether tailoring the Kp and Ki values of a proportional-integral (PI) controller during radiofrequency (RF) cardiac ablation could be advantageous from the point of view of the dynamic behaviour of the controller, in particular, whether control action could be speeded up and larger lesions obtained. METHODS: Theoretical models were built and solved by the finite element method. RF cardiac ablations were simulated with temperature controlled at 55°C. Specific PI controllers were implemented with Kp and Ki parameters adapted to cases with different tissue values (specific heat, thermal conductivity and electrical conductivity) electrode-tissue contact characteristics (insertion depth, cooling effect of circulating blood) and electrode characteristics (size, location and arrangement of the temperature sensor in the electrode). RESULTS: The lesion dimensions and T(max) remained almost unchanged when the specific PI controller was used instead of one tuned for the standard case: T(max) varied less than 1.9°C, lesion width less than 0.2 mm, and lesion depth less than 0.3 mm. As expected, we did observe a direct logical relationship between the response time of each controller and the transient value of electrode temperature. CONCLUSION: The results suggest that a PI controller designed for a standard case (such as that described in this study), could offer benefits under different tissue conditions, electrode-tissue contact, and electrode characteristics.
Alba-Martínez et al. (Tue,) conducted a other in Radiofrequency cardiac ablation. Tailored proportional-integral (PI) controller vs. Standard PI controller was evaluated on Lesion dimensions and T(max). Using a specific PI controller tailored to different tissue and electrode conditions resulted in minimal changes to T(max) (<1.9°C) and lesion dimensions (<0.3 mm) compared to a standard controller.