High-Density and High-Coverage Composite Atrial Activation Maps: An In-Silico Validation Study

Objective: Repetitive atrial activation patterns (RAAPs) during complex atrial tachycardia could be associated with localized mechanisms that can be targeted. Clinically available electroanatomical mapping systems are limited by either the spatial coverage or electrode density of the mapping catheters, preventing the adequate visualization of transiently occurring RAAPs. This work proposes a technique to overcome this shortcoming by stitching spatially overlapping conduction patterns together to a larger image- called a composite map. Methods: Simulated stable mechanisms and meandering reentries are sequentially mapped (4 × 4 grid, 3 mm spacing) and then reconstructed back to the original sizes with the proposed recurrence plot-based algorithm. Results: The reconstruction of single linear waves presents minimal errors (local activation time (LAT) difference: 3.2 [1.6–4.9] ms, conduction direction difference: 5.2 [2.3–8.0] degrees). Errors significantly increase (p<0.05) for more complex patterns, being the highest with unstable reentries (LAT difference: 10.3 [3.5–16.2] ms, conduction direction difference: 18.2 [6.7–29.7] deg). In a second part of the analysis, 111 meandering reentries are reconstructed. Mapping 30 locations overlappingly around each reentry core was found to be the optimal mapping strategy. For this optimal setting, LAT, conduction direction, and core localization errors are low (6.1 [4.2–8.6] ms, 11.2 [8.6–15.5] deg and 4.1 [2.9–4.9] mm, respectively) and are weakly correlated with the degree of the meander ($\rho$ = 0.41, $\rho$ = 0.40 and $\rho$ = 0.20, respectively). Conclusion: Our findings underline the feasibility of generating composite maps by stitching spatially overlapping recordings. Significance: Composite maps can be instrumental in personalized ablation strategies.