“…The inability to combine low-and high-resolution mapping in the intact human heart may also explain why measures of organization and spatial gradients in AF, such as dominant frequency, organizational index, and Shannon entropy, have proven unstable and of no significant clinical utility. 12,13 That the hierarchical nature of AF organization is only revealed at the most global level using complex algorithms may be considered to obviate the need to understand causation at the cell and tissue level. But this would once again make us slaves to the empirical-like when pulmonary vein encirclement only, with or without the aim of isolation was uniformly applied for all clinical presentations of AF, 14 or when variably defined attractive electrograms 15 were indiscriminately ablated as the empirical adjunct.…”