1 3-dimensional simulation of long QT syndrome: early afterdepolarizations and reentry
نویسندگان
چکیده
Early afterdepolarizations (EADs), thought to be highly arrhythmogenic in the case of long QT (LQT) syndromes, are most readily observed at slow heart rates and suppressed by fast heart rates. However, EADs are thought to contribute to tachycardia-dependent arrhythmias such as Torsades des pointes and ventricular fibrillation, leading to sudden cardiac death. Recent studies of simulated LQT in 1D and 2D tissues have suggested a possible mechanism by which EADs could occur at rapid heart rates as a sequela of spontaneous sarcoplasmic reticulum (SR) Ca release related to intracellular Ca overload. These EADs could then lead to reinitiation of 1D and spiral wave reentry that otherwise would have self-terminated. This paper extends these results to simulated LQT in 3D tissue and shows that the appearance of EADs can similarly reinitiate scroll wave reentry.
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