Relationship Between Ablation Lesion Size Estimated by Ablation Index and Different Ablation Settings—an Ex Vivo Porcine Heart Study


This study aimed to verify the reliability of ablation index (AI) for ablation lesion estimating with different settings for radiofrequency (RF) parameters: power, impedance, contact angles, irrigation rate, temperature of irrigation saline, and irrigation solution. RF ablations (N = 66) were performed on ex vivo porcine left ventricle submerged in 37 °C saline. The aforementioned ablation parameters were changed to measure whether the size of the ablation lesion was consistent at a fixed AI value of 500. The maximum lesion diameter (r = − 0.631, P = 0.028), depth (r = − 0.896, P < 0.001), and volume (r = − 0.745, P < 0.005) were significantly reduced with an increase of the impedance. The lesion depth (P < 0.05) and the lesion volume (P < 0.05) were significantly larger with glucose irrigation than saline irrigation. In conclusion, at a fixed AI value, impedance and irrigation solution have impact on the ablation lesions, which could affect the accuracy of AI formula to estimate ablation lesion size.

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Atrial fibrillation


Ablation index


Contact force


Pulmonary vein isolation






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We thank Wen-Hao Huang, Chi Zhang, and Yi-Xin Wang for operating the Carto System.


This work was supported by the National Key Research and Development Program of China (2017YFC0908803, 2017YFC0908800, 2018YFC1312501), the Beijing Municipal Science and Technology Commission (Z181100001718105, Z181100001718174), and the National Natural Science Foundation of China (81530016, 81870243).

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Correspondence to Ri-Bo Tang.

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Huang, S., Dong, J., Du, X. et al. Relationship Between Ablation Lesion Size Estimated by Ablation Index and Different Ablation Settings—an Ex Vivo Porcine Heart Study. J. of Cardiovasc. Trans. Res. (2020).

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  • Ablation index
  • Impedance
  • Radiofrequency ablation