Abstract 13639: Comparison of the Flexible Tip Irrigated Catheter to the Rigid Tip Irrigated Catheter in a Porcine Thigh Muscle Preparation.
Introduction: The flexible fully irrigated catheter has been introduced to reduce formation of char and coagulum at the catheter tissue interface and also to conform to the endocardial surface for better contact.
Hypothesis. Ablation with a 4mm flexible electrode tip fully-irrigated catheter (CF: Therapy Cool Flex TM, SJM) compared to ablation with a 4mm traditional 6-hole rigid electrode open irrigated catheter (CP: Therapy Cool Path™, SJM) will result in better lesion characteristics.
Methods: Under the same settings lesions were created in a thigh muscle preparation with the CF and CP catheters in 7 pigs. Post procedure 2,3,5 triphenyltetrazolium chloride (TTC) was injected into the femoral artery to demarcate ablated from non ablated tissue. The thigh muscle was then excised and fixed with formalin solution and examined grossly. All lesion measurements were performed in a blinded manner to catheter type and settings.
Results: A total of 196 lesions (101 CP and 95 CF) were performed using the same parameters with both catheters. The average temperature using the CF catheter was 31±3 °C vs. 36±4°C (p=0.0001) with the CP catheter. The maximum temperature with the CF catheter was 35 ± 4°C vs. 41±4°C (p=0.0001) with the CP catheter despite higher average power achieved with the CF (37±9 W vs. 34±8 W, p=0.0042). The lesion diameter at the surface was larger with the CF vs CP catheter (10.33±2.41mm vs. 9.56±1.68mm, p=0.01). While there was no difference in lesion depth (5.92±1.91 mm CF vs. 5.51.±1.63 mm CP) or depth to maximum lesion diameter (2.79±1.08mm CF vs. 2.74±0.82 CP, p=0.75) the maximum diameter was larger with the CF catheter (11.09±2.64mm vs. 10.34±2.07mm, p=0.03).There was no char or coagulum formation on either catheter. However ablation with the CP catheter resulted in tissue char in 5% of lesions. No tissue char was noted with the CF catheter.
Conclusion: Ablation with the CF catheter compared to the CP catheter resulted in less tissue interface heating allowing ablation with higher output power and resulting in larger lesions at similar depths with no char or coagulum formation. These findings may be due to better cooling achieved with the fully irrigated flexible design in addition to better conformity and may translate into better outcomes in clinical studies.
- © 2011 by American Heart Association, Inc.