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Electrocardiogram Recordings in Anesthetized Mice using Lead II
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Cardiac memory induced by QRS widening due to propafenone toxicity

John V Wylie1, Peter Zimetbaum, Mark E Josephson

  • 1Harvard-Thorndike Electrophysiology Institute,Harvard Medical School, Boston, Massachusetts, USA.

Pacing and Clinical Electrophysiology : PACE
|August 30, 2007
PubMed

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Class III antiarrhythmic drugs are a group of medications that can prolong action potentials in the heart. They achieve this by blocking potassium channels or enhancing inward currents from sodium channels. However, these drugs have a unique property of "reverse use-dependence," which is most pronounced at slower heart rates and can lead to torsades de pointes—a specific type of arrhythmia. However, it is essential to note that excessive QT interval prolongation—a measure of the heart's...
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