Convective cooling effect on cooled-tip catheter compared to large-tip catheter radiofrequency ablation.

Background: Both actively cooled-tip and large-tip catheters are currently available clinically to create large endomyocardial lesions during application of radiofrequency (RF) energy. The purpose of this study was to compare the effect of convective cooling at physiologic flow rates on RF lesion size using both actively cooled and large-tip catheters.

Methods: Porcine hearts were sectioned into 72 pieces and placed in a temperature-controlled saline bath (37 degrees C) with varying directed flow rates (0, 1, 2, and 3 L/min).