P1863Establishing safe working parameters for radio frequency catheterization along with acoustic sensing

Abstract

Abstract Background Studies comparing angles of application in Radio Frequency (RF) catheter ablation other than 0 and 90 degrees are absent from the literature. Likewise, using acoustics to predict steam pop occurrences and prevent a catastrophic rupture of the myocardium has not been examined previously. Purpose Evaluate the effect of various parameters on the ablated volume and the probability of creating a boiling pop. Methods A low-cost testing and educational platform to work with generic RF catheters was set up. The in-vitro system allows controlling the blood flow surrogate over the cardiac tissue, the catheter contact force, electric power, and ablation time. Acoustic transducers have been employed with the setup to detect preliminary acoustic signals. Results Obtained results show a positive correlation between variations of the ablated surface geometry and power intensity changes. Generated figures provide percentages of a boiling pops for any given set of parameters fig1 (Top left: Probability of popping vs power and time). The probability of a boiling pop occurring increased if the ovine specimen is non-irrigated. The ratio of the burn correlates with the power and the angle of the catheter (30°, 45°, 60°, and 90°). However, the probability of the popping mostly depends on the power fig1 (Top right: Burn ratio vs power for 30°, 45°, 60°, and 90°) and fig1 (Bottom right: Cross sectional view of the corresponding lesions -same scale used for all images). Benign precursory bubbles detected by acoustics preceded the occurrence of catastrophic boiling pops fig1 (Bottom left: Acoustic signal showing a precursory pop before the major cavitation). Figure 1 Conclusion The established parameters for power intensity and exposure time should be respected to maintain a safe procedure. Acoustics can be further implemented to provide a warning for electrophysiologists before the occurrence of a boiling pop. Acknowledgement/Funding The funding for this project was provided from the URB and the MPP at the AUBMC and the AUB.