Rabbit model to simulate the residual conduction gaps after radiofrequency ablation on the anterior wall of left atrial appendage

  • Huaner Ni
  • Ying Zhuge
  • Lin Li
  • Weifeng Li
  • Congcong Zhao
  • Yujie Wang
  • Fang Wang



Radiofrequency ablation (RFA) is widely used to treat patients with atrial fibrillation (AF), but its recurrence rate is still high mainly due to pulmonary vein reconnection and residual conduction gaps. We aim to establish a rabbit model to simulate the residual conduction gaps after ablation.


Sixty-nine adult New Zealand white rabbits were randomly assigned to six groups. RFA on the anterior wall of left atrial appendage (LAA) were performed with the ablation power from 6 to 21 W. The electrophysiological pacing and mapping technology was used to evaluate the bidirectional conduction of LAA. Histological study and fluorescence techniques were used to evaluate the effect of RFA and the accumulation of drug-loaded liposome on the loop ablation lesions of LAA.


Typical loop ablation lesions of LAA could be observed in vivo and vitro of rabbit models. Histological evaluation revealed coagulative necrosis on the loop ablation lesions. Electrical conduction between inside and outside loop lesions recovered after 1 or 2 weeks after initial unidirectional conduction block. The recurrence rates were significantly different among six groups with varying ablation powers (p < 0.05). Compared with exit conduction block, entrance conduction block was significantly different at 5 min after ablation (p = 0.02). IR-775-loaded liposomes were accumulated on the loop ablation lesions at 48 h after RFA.


RFA associated with electrophysiological pacing and mapping technology successfully established a novel rabbit model to simulate the residual conduction gaps after RFA.


Radiofrequency ablation Residual conduction gaps Recovered electrical conduction Rabbit model Inflammation-targeted drugs 



We thank for the support of grants (16140901400) from the Science and Technology Commission of Shanghai Municipality.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All animal protocols in this study were approved by the Animal Care and Use Committee, Research Institute of Medicine, Shanghai Jiao Tong University, in accordance with the guide for the Care and Use of Laboratory Animals published by the National Institutes of Health (Publication No. 85–23, revised 1996).

Informed consent

Informed consent was not required.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Huaner Ni
    • 1
  • Ying Zhuge
    • 1
  • Lin Li
    • 2
  • Weifeng Li
    • 1
  • Congcong Zhao
    • 2
  • Yujie Wang
    • 2
  • Fang Wang
    • 1
  1. 1.Department of Cardiology, Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghaiPeople’s Republic of China
  2. 2.Department of Pharmaceutics, School of PharmacyEast China University of Science and TechnologyShanghaiPeople’s Republic of China

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