Evaluation of the anatomopathological characteristics and the safety of radiofrequency lesions at the atrial level with two different systems of irrigated tip catheters on an experimental level

Introduction and objectives. We performed this study to evaluate the securi ty and efficacy in the lesions produced on the atrial wall by different irr igated catheters in an experimental model. We evaluated the anatomopatholog ic characteristics of the lesions produced by two different systems of irri gated tip catheters, with opened or closed circuit. Methods. This study was performed in 16 pigs applying 60 sec radiofrequency pulses with three different energy levels (15, 25 y 50 Watts). Two differe nt systems of radiofrequency ablation irrigated catheters were used, opened and closed. We used 4 pigs in which we performed ablation with a standard catheter as a control group. Under fluoroscopic guidance, catheters were pl aced on the high and low right atrial lateral wall, where lesions were prod uced. After 7 days, animals were sacrified for anatomopathological study. Results. A total of 27 lesions were performed with irrigated catheters (11 closed circuit and 16 opened) and 6 with standard catheters in the control group. We did not find significant differences in the lesion characteristic s between the two different systems of irrigated tip catheter used, neverth eless lesions performed with the closed system were slightly greater. Th le sions produced with irrigated catheters were always superior in the control group. Transmurality in the free atrial wall is frequent with both systems . We did not see any perforation in the atrial wall. Conclusions. We did not find significant differences in the size of the les ions produced with the two systems of irrigated catheters used. These data from an experimental model can provide useful information for atrial tachyc ardia radiofrequency ablation procedures in humans.