New atrial fibrillation model with endocardial approach by CRT bi-electrode atrial pacing in mini-pigs

Objective: To evaluate the model of atrial fibrillation (AF) in mini-pigs with endocardial approach implantation CRT-P using bi-electrodes pacing through RV/LV connectors.Methods: All surgical interventions were minimally invasive and conducted under general anaesthesia. was implanted endocardially, X-ray. First electrode fixed right appendage. The second one — interatrial septum or free wall. Both them connected RV/LV. Bi-electrode stimulation realized during a week basic heart rate 150 bpm delay between electrodes 80 ms (mean 450 bpm), which corresponds to (HR) AF. Electrophysiological study performed experiment analyze cardiac conduction system. AF inducibility evaluated before after stimulation.Results: A series experiments demonstrated that there no complications following device implantation. There non-sustained paroxysm permanent three pigs. After we noted tendency increase baseline HR (average frequency from 94 ± 4 98 6 bpm). Non-sustained induced all cases. sustained 92 min burden pig.Conclusion: Endocardial bi-electrode has proven be safe. This improves can considered as an alternative epicardial for employing models. Received December 2022. Revised 17 January 2023. Accepted 18 Funding: supported by Russian Science Foundation (project No. 22-25-00672). Conflict interest: authors declare conflict interest. Contribution authorsConception design: V.V. Beloborodov, D.V. Losik, E.V. FisherData collection analysis: Fisher, A.G. FilippenkoDrafting article: V.I. Murtazin, BeloborodovCritical revision A.B. Romanov, Shabanov, I.L. MikheenkoFinal approval version published: Filippenko, Mikheenko, Romanov