Spatiotemporal Correlation Analysis of Cardiac Activation Patterns in Langendorff-Perfused Human Hearts: Insights for Arrhythmia Prediction

Electric instabilities in cardiac dynamics, arising in the form of action potential duration alternans in time and space, are well-established precursors of arrhythmias and ventricular fibrillation leading to sudden cardiac death. Mechanisms associated with the appearance of these instabilities were pointed out to be linked both to cellular-level features and to the dynamic response of cardiac tissues resulting from heterogeneity and anisotropy. In this framework, transmural dispersion has been shown to play a fundamental role in shaping the evolution of alternans patterns and in the degeneration of cardiac rhythms into fibrillation. This contribution presents a case of study of human heart endocardium and epicardium surfaces during pacing-down restitution protocols recorded through optical mapping. We quantify alternans onset and development on both surfaces, further investigating differences in conduction velocity and correlation properties. Our results show a significant dispersion between endocardium and epicardium, corroborating the prominent role of such a biomarker in predicting arrhythmias and fibrillation.