Key result
Intravenous MS-551 prolongs VERP by ~28 msec in a reverse use-dependent manner.
Why the study?
The electrophysiologic effects of intravenous MS-551, a novel class III antiarrhythmic drug, on human atrium and ventricle were not previously evaluated.
Does intravenous MS-551 alter electrophysiologic parameters and prevent induction of ventricular tachyarrhythmias in patients with VT/VF?
Does intravenous MS-551 alter electrophysiologic parameters and prevent induction of ventricular tachyarrhythmias in patients with VT/VF?
Absolute Event Rate: 268% vs 240%
p-value: p=<0.0001
Intravenous MS-551 exhibits pure class III antiarrhythmic properties with reverse use-dependent prolongation of refractoriness, but its clinical efficacy for preventing VT/VF requires further evaluation at higher doses.
No takes yet. Share an insight, caveat, or question.
MS-551 prolongs atrial/ventricular ERPs without affecting conduction in VT/VF patients; leaves open clinical efficacy pending larger trials.
Naitoh et al. (1998) studied Ventricular tachyarrhythmias (n=6). Intravenous MS-551 vs. Baseline (before administration) was evaluated on Right ventricular effective refractory period (VERP) at paced cycle length of 600 msec (p=<0.0001). Intravenous MS-551 significantly prolonged the right ventricular effective refractory period from 240 to 268 msec at a paced cycle length of 600 msec in a reverse use-dependent manner.
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