Atrial fibrillation source area probability mapping using electrogram patterns of multipole catheters

Abstract

Background Catheter ablation therapy involving isolation of pulmonary veins (PVs) from the left atrium is performed to terminate atrial fibrillation (AF). Unfortunately, standalone PV isolation procedure has shown to be a suboptimal success with AF continuation or recurrence. One reason, especially in patients with persistent or high-burden paroxysmal AF, is known to be due to the formation of repeating-pattern AF sources with a meandering core inside the atria. However, there is a need for accurate mapping and localization of these sources during catheter ablation. Methods A novel AF source area probability (ASAP) mapping algorithm was developed and evaluated in 2D and 3D atrial simulated tissues with various arrhythmia scenarios and a retrospective study with three cases of clinical human AF. The ASAP mapping analyzes the electrograms collected from a multipole diagnostic catheter that is commonly used during catheter ablation procedure to intelligently sample the atria and delineate the trajectory path of a meandering repeating-pattern AF source. ASAP starts by placing the diagnostic catheter at an arbitrary location in the atria. It analyzes the recorded bipolar electrograms to build an ASAP map over the atrium anatomy and suggests an optimal location for the subsequent catheter location. ASAP then determines from the constructed ASAP map if an AF source has been delineated. If so, the catheter navigation is stopped and the algorithm provides the area of the AF source. Otherwise, the catheter is navigated to the suggested location, and the process is continued until an AF-source area is delineated. Results ASAP delineated the AF source in over 95% of the simulated human AF cases within less than eight catheter placements regardless of the initial catheter placement. The success of ASAP in the clinical AF was confirmed by the ablation outcomes and the electrogram patterns at the delineated area. Conclusion Our analysis indicates the potential of the ASAP mapping to provide accurate information about the area of the meandering repeating-pattern AF sources as AF ablation targets for effective AF termination. Our algorithm could improve the success of AF catheter ablation therapy by locating and subsequently targeting patient-specific and repeating-pattern AF sources inside the atria.

Computational Analysis of Mapping Catheter Geometry and Contact Quality Effects on Rotor Detection in Atrial Fibrillation

“…The latter one was more robust toward missing electrodes. Due to the different types of catheters employed in Ganesan et al (2020), a direct comparison with our results is difficult. However, notably, both HDGrid and PentaRay catheters we simulated were more robust, being able to detect the AF driver with 50% of non-contact electrodes and with a much smaller estimation error compared to the resolution of the method proposed in Ganesan et al (2020) no simulation to test the effect of the catheter-LA wall distance was performed.…”

“…A few recent studies ( Ganesan et al, 2020 ; Ravikumar et al, 2021 ) aimed at validating new algorithms for rotor detection, and simulated EGM acquisition using different mapping catheters.…”

“…A few recent studies (Ganesan et al, 2020;Ravikumar et al, 2021) aimed at validating new algorithms for rotor detection, and simulated EGM acquisition using different mapping catheters. Ganesan et al (2020) have described a mapping algorithm that delineated the area of meandering repeating-pattern AF sources suggesting an optimal position for the subsequent catheter location.…”

“…A few recent studies (Ganesan et al, 2020;Ravikumar et al, 2021) aimed at validating new algorithms for rotor detection, and simulated EGM acquisition using different mapping catheters. Ganesan et al (2020) have described a mapping algorithm that delineated the area of meandering repeating-pattern AF sources suggesting an optimal position for the subsequent catheter location. This new algorithm was validated using EGMs acquired with two catheters (Lasso and spiral catheters) at different electrode-wall distances and simulating non-optimal contact conditions by making electrograms randomly isoelectric.…”

How synergy between mechanistic and statistical models is impacting research in atrial fibrillation

“…Ganesan et al developed and evaluated the AF source area probability (ASAP) mapping algorithm in 2D and 3D atrial simulated tissues with various arrhythmia scenarios and a retrospective study with three cases of clinical human AF. They found that ASAP delineated the AF source in over 95% of the simulated human AF cases within less than eight catheter placements regardless of the initial catheter placement ( Ganesan et al, 2020 ). The study of Sánchez et al characterized atrial fibrotic substrate with a hybrid in silico and in vivo dataset and found the digital twin techniques can overcome a single voltage cut-off value to identify fibrotic tissue from intracardiac signals ( Sánchez et al, 2021 ).…”