PO-616-05 THE INSPECTION PARADOX: AN IMPORTANT CONSIDERATION IN THE EVALUATION OF ROTOR LIFETIMES IN CARDIAC FIBRILLATION

Abstract

Renewal theory is a statistical approach to model the formation and destruction of phase singularities (PS), which occur at the pivots of spiral waves. A common issue arising during observation of renewal processes is an inspection paradox, due to oversampling of longer events. We hypothesized that an inspection paradox could influence the perception of PS lifetimes in cardiac fibrillation recordings, leading to a potential overemphasis on the importance of long lifetime PS. We characterise the effect of a potential inspection paradox in 8 systems of human, animal, and computational fibrillation. Computational simulations (Aliev-Panfilov (APV) model, 2D & 3D Atrial Fibrillation (AF) models), experimentally acquired optical mapping AF and Ventricular Fibrillation (VF) data, and clinically acquired human AF and VF were studied. Distributions of all PS lifetimes across full epochs of AF, VF, or computational simulations, were compared with distributions formed from lifetimes of PS existing at 10000 simulated commencement timepoints. In all systems, an inspection led towards oversampling of PS with longer lifetimes. In APV simulations a PS lifetime shift of +111.8% 1.9% (P < 0.001 for observed vs overall), in realistic 2D simulations of AF +692.9% ±57.7% (P < 0.001), in a 3D computation simulation +691.7%, in optically mapped rat AF +374.6% 88.5% (P = 0.052), in human AF mapped with basket catheters +129.2% ±4.1% (P < 0.05), human AF-HD grid catheters 150.8% 9.0% (P < 0.001), in optically mapped rat VF +171.3% ±15.6% (P < 0.001), in human epicardial VF 153.5% ±15.7% (P < 0.001). This multi-system study of human, animal, computational atrial and ventricular fibrillation is an illustration of the fundamental importance of an inspection paradox as a source of bias in phase mapping.