afterdepolarization

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afterdepolarization

 [af″ter-de-po″lah-rĭ-za´shun]
an oscillation in membrane potential that is dependent upon a preceding action potential for its initiation, and which upon reaching threshold potential can induce arrhythmias that are said to be “triggered.” Early afterdepolarizations occur during phases 2 and 3 of repolarization; delayed afterdepolarizations follow full repolarization.
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References in periodicals archive ?
Hool, "Contributions of ion channel currents to ventricular action potential changes and induction of early afterdepolarizations during acute hypoxia," Circulation Research, vol.
This spontaneous [Ca.sup.2+] leakage can result in sodium [Ca.sup.2+] exchanger (NCX) triggered early and/or delayed afterdepolarizations (EADs/DADs) and arrhythmias in CMs [4].
Qu, "Calcium-voltage coupling in the genesis of early and delayed afterdepolarizations in cardiac myocytes," Biophysical Journal, vol.
Weiss, "Multiscale Consequences of Spontaneous Calcium Release on Cardiac Delayed Afterdepolarizations," Biophysical Journal, vol.
This can cause early afterdepolarizations (EADs) from inward depolarizing currents through T-type calcium channels or sodium channels which appear as U waves on ECG.
Early afterdepolarizations (EADs) from the right ventricular epicardial surface triggered VT, which degenerated to ventricular fibrillation [3].
In addition, Xue et al .[sup][15] have found that, in the rabbit models, Wenxin Keli suppressed early afterdepolarizations, delayed afterdepolarizations, and triggered ventricular arrhythmias via selective inhibition of the late I[sub]Na that is proved to contribute to arrhythmogenesis.[sup][21] The other possible mechanisms underlying the ventricular anti-arrhythmic effect of Wenxin Keli observed in this study included abolishing rate-dependent change in repolarization and indirectly alleviating intracellular Ca [sup]2+ overloads via reducing the sodium influx.
Wang, "Inhibitory effects of tetramethylpyrazine on early afterdepolarizations induced by calcium paradox injury in myocardium of rats ex vivo," Chinese Journal of Clinical Rehabilitation, vol.
Nocturnal prolonged cycle lengths can facilitate the occurrence of early afterdepolarizations and ventricular arrhythmias including torsades de pointes.
In the study, Gideon Koren, M.D., a physician researcher and colleagues studied early afterdepolarizations (EADs), an abnormal depolarization during the plateau phase of the heart electrical activity (action potential) that can initiate arrhythmia, and a hallmark of LQTS.
Canine left ventricular hypertrophy predisposes to ventricular tachycardia induction by phase 2 early afterdepolarizations after administration of BAY K 8644.