J Interv Card Electrophysiol. 2026 Jun 18. doi: 10.1007/s10840-026-02361-3. Online ahead of print.
ABSTRACT
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.
PMID:42313340 | DOI:10.1007/s10840-026-02361-3
