Simulated atrial sheets with increased adrenergic stimulation spatial densities maintained rotors longer than those with minimally conductive elements (2.6 ± 0.1 s vs. 1.5 ± 0.2 s, p<0.001).
Does increased spatial density of adrenergic stimulation alter rotor behavior in simulated atrial sheets compared to structural remodeling?
Simulated sympathetic hyperactivity via dense adrenergic stimulation maintains atrial rotors longer and with higher angular speed than structural remodeling, suggesting a mechanism for pro-arrhythmic substrates in autonomic derangements.
Absolute Event Rate: 2.6% vs 1.5%
p-value: p=<0.001
Sympathetic hyperactivity via spatially dense adrenergic stimulation may create pro-arrhythmic substrates even without structural remodelling. However, the effect of sympathetic hyperactivity on arrhythmic activity, such as rotors, is unknown. Using simulations, we examined the effects of gradually increasing the spatial density of adrenergic stimulation (AS) in atrial sheets on rotors. We compared their characteristics against rotors hosted in atrial sheets with increasing spatial density of minimally conductive (MC) elements to simulate structural remodelling due to injury or disease. We generated rotors using an S1-S2 stimulation protocol. Then, we created phase maps to identify phase singularities and map their trajectory over time. We measured each rotor's duration (s), angular speed (rad/s), and spatiotemporal organization. We demonstrated that atrial sheets with increased AS spatial densities could maintain rotors longer than with MC elements (2.6 ± 0.1 s vs. 1.5 ± 0.2 s, p<0.001). Moreover, rotors have higher angular speed (70 ± 7 rads/s vs. 60 ± 15 rads/s, p<0.05) and better spatiotemporal organization (0.56 ± 0.05 vs. 0.58 ± 0.18, p<0.05) in atrial sheets with less than 25% AS elements compared to MC elements. Our findings may help elucidate electrophysiological potential alterations in atrial substrates due to sympathetic hyperactivity, particularly among individuals with autonomic derangements caused by chronic distress.
Magtibay et al. (Thu,) conducted a other in Atrial arrhythmias. Adrenergic stimulation (AS) spatial density vs. Minimally conductive (MC) elements was evaluated on Rotor duration (s) (p=<0.001). Simulated atrial sheets with increased adrenergic stimulation spatial densities maintained rotors longer than those with minimally conductive elements (2.6 ± 0.1 s vs. 1.5 ± 0.2 s, p<0.001).