Cooled intramural needle catheter ablation created significantly deeper lesions than conventional irrigated tip catheter ablation (13.5 vs 9.1 mm, P<0.01) with no tissue popping.
Does cooled intramural needle catheter ablation create deeper lesions than irrigated tip catheter ablation in an ex vivo sheep heart model?
A prototype cooled intramural needle ablation catheter creates significantly deeper lesions without tissue popping compared to conventional irrigated tip catheters in an ex vivo model.
Absolute Event Rate: 13.5% vs 9.1%
p-value: p=< 0.01
Endocardial radiofrequency ablation of the left ventricle does not create transmural lesions reliably even with active electrode cooling. The authors developed a prototype catheter with an internally cooled needle electrode that could be advanced an adjustable distance into the myocardium. Freshly excised hearts from eight male sheep were perfused and superfused using oxygenated ovine blood. Ablations were performed for 2 minutes using the prototype catheter and a conventional endocardial 5-mm irrigated tip ablation catheter at target temperatures of 80 degrees C and 50 degrees C, respectively. The prototype catheter needle was inserted 12 mm deep for all ablations. The maximal power and irrigation rate was 50 W, 20 mL/min for the irrigated tip catheter and 20 W, 10 mL/min for the intramural needle catheter. Intramural needle lesions were significantly deeper (13.5 +/- 2.3 vs 9.1 +/- 1.3 mm, P < 0.01) but less wide (8.7 +/- 1.5 vs 12.7 +/- 1.9 mm, P < 0.01) than irrigated tip lesions. Popping occurred during 12 (37%) of the 32 irrigated tip ablations. Popping did not occur during intramural needle ablation. The cooled intramural needle ablation catheter creates lesions that are significantly deeper than irrigated tip catheters with less tissue boiling. In contrast to irrigated tip ablation, electrode temperature monitoring can be used to determine if a lesion has been created during intramural needle ablation. The cooled intramural needle ablation lesions were of a clinically useful width, addressing one of the main recognized deficiencies of intramural needle ablation.
Thiagalingam et al. (Thu,) conducted a other in Radiofrequency ablation of the left ventricle (n=8). Cooled intramural needle catheter ablation vs. Conventional endocardial 5-mm irrigated tip ablation catheter was evaluated on Lesion depth (mm) (p=< 0.01). Cooled intramural needle catheter ablation created significantly deeper lesions than conventional irrigated tip catheter ablation (13.5 vs 9.1 mm, P<0.01) with no tissue popping.