Longer inter-lesion intervals during 90 W, 4-s ultra-high-power short-duration ablation were associated with a more gradual temperature rise and significantly lower peak temperatures (P<0.0001).
Does the inter-lesion time interval affect tissue temperature rise during ultra-high-power short-duration ablation in an ex vivo porcine model?
Longer inter-lesion intervals (≥40 seconds) during ultra-high-power short-duration ablation prevent excessive tissue temperature rise in an ex vivo model.
p-value: p=< 0.0001
Background Esophageal injury following radiofrequency ablation for atrial fibrillation is closely associated with esophageal temperature. Studies suggest that discontinuous ablation may prevent excessive esophageal temperature rise; however, the temperature characteristics of discontinuous ablation strategy during ultra-high-power short-duration ablation remain unexplored. Methods Fresh porcine cardiac tissue was used. A 15-mm deep vertical hole was drilled from the endocardial surface, and a temperature probe was inserted. The QDOT catheter (Biosense Webster) was positioned at the endocardial site of probe insertion, and the lesion was created using a 90 W, 4-s ablation strategy. After a predefined interval, a second lesion was created.Based on the inter-lesion time interval, samples were divided into four groups: 10 s (group 1), 20 s (group 2), 40 s (group 3), and 60 s (group 4). Temperature was recorded every 10 s. Results Temperature curves in groups 1 and 2 exhibited a unimodal pattern, whereas groups 3 and 4 showed a bimodal pattern. Mean peak temperatures differed among groups: group 1, 39.1 °C (38.6–39.5 °C); group 2, 38.4 °C (38.0–38.7 °C); group 3, peak 38.0 °C (37.5–38.2 °C) with a sub-peak of 37.3 °C (37.1–37.5 °C); group 4, peak 37.8 °C (37.5–38.0 °C) with a sub-peak of 37.3 °C (36.9–37.6 °C). Peak temperatures differed significantly among groups (P < 0.0001). Analysis of repeated temperature measurements revealed a statistically significant between-groups effect (F = 7.2, P < 0.002). Using < 38.5 °C as a safety threshold for peak temperature, 8 cases (73.3%) in group 1 exceeded the threshold, 4 cases (27%) in group 2 reached the threshold, whereas neither group 3 nor group 4 exceeded it. Conclusion Tissue temperature demonstrates significant delayed and cumulative effects during ultra-high-power short-duration ablation. In our ex vivo model, longer inter-lesion intervals were associated with a more gradual temperature rise.
LIU et al. (Thu,) conducted a other in Atrial fibrillation (ex vivo model). Inter-lesion time intervals (10 s, 20 s, 40 s, and 60 s) during ultra-high-power short-duration ablation vs. Different time intervals was evaluated on Peak tissue temperature (p=< 0.0001). Longer inter-lesion intervals during 90 W, 4-s ultra-high-power short-duration ablation were associated with a more gradual temperature rise and significantly lower peak temperatures (P<0.0001).