Successful stimulation of myocardial ganglionic plexuses by TAU 20 in the absence of cardiac damage

Li, S.; Kay, J. A.; Agha-Jaffar, D.; S Y Gao, C.; Perkins, J.; Koustsoftidis, S.; Mic, D. E.; Cantwell, C. D.; Wang, L.; Kanagaratnam, P.; Chowdhury, R. A.

doi:10.1101/2024.09.16.613202

bioRxiv · 10.1101/2024.09.16.613202

Successful stimulation of myocardial ganglionic plexuses by TAU 20 in the absence of cardiac damage

Li, S.·Kay, J. A.·Agha-Jaffar, D.·S Y Gao, C.·Perkins, J.·Koustsoftidis, S.·Mic, D. E.·Cantwell, C. D.·Wang, L.·Kanagaratnam, P.·Chowdhury, R. A.

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Abstract

Atrial fibrillation (AF) is a major healthcare burden worldwide. For AF that is resistant to pharmacological intervention, the standard invasive treatment is a pulmonary vein isolation (PVI) procedure. Ganglionated plexuses (GP) ablation can be used as an adjunctive therapy to PVIs, together reducing the likelihood of AF recurrence. High-frequency stimulation (HFS) is a technique used to identify ectopy-triggering GP sites. However, to locate GP sites, sequential HFS must be delivered over the whole atria. Therefore, ensuring the safety of HFS delivery is integral to avoid causing irreversible damage from excessive pacing. We tested Tau-20 version 2 neural simulator, a prototype of a novel electrophysiological pacing and recording system that has the potential to guide intracardiac AF treatments. Using an ex vivo porcine Langendorff model that closely resembles the anatomy and physiology of a human heart, we confirmed that HFS can successfully trigger AF, indicating that HFS-positive locations contain GP sites. Additionally, we found that the HFS delivered via Tau-20 version 2 did not cause any damage to the heart. These findings evidence that once fully optimised, the Tau-20 system could be suitable for use in clinical settings.

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Li, S., Kay, J. A., Agha-Jaffar, D., S Y Gao, C., Perkins, J., Koustsoftidis, S., Mic, D. E., Cantwell, C. D., Wang, L., Kanagaratnam, P., Chowdhury, R. A.. 2024-09-19. Successful stimulation of myocardial ganglionic plexuses by TAU 20 in the absence of cardiac damage. https://doi.org/10.1101/2024.09.16.613202

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