A novel approach to identifying antiarrhythmic drug targets

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Updated: Sep 27, 2026

High-throughput Screening for Small-molecule Modulators of Inward Rectifier Potassium Channels
10:07

High-throughput Screening for Small-molecule Modulators of Inward Rectifier Potassium Channels

Published on: January 27, 2013

Robert F Gilmour1

  • 1Dept of Biomedical Sciences, T7 012C VRT, Cornell University, Ithaca, NY 14853-6401, USA. rfg2@cornell.edu

Drug Discovery Today
|February 13, 2003
PubMed

Insights

Sudden cardiac death from ventricular fibrillation (VF) may be caused by spiral wave re-entry. Targeting electrical restitution may offer a new antiarrhythmic therapy by suppressing VF.

Area of Science:

  • Cardiology
  • Cardiac Electrophysiology
  • Medical Science

Background:

  • Sudden cardiac death (SCD) is the leading cause of mortality in the USA.
  • Ventricular fibrillation (VF) is a primary cause of SCD.
  • VF may originate from spiral wave re-entry in cardiac tissue.

Purpose of the Study:

  • To investigate the link between electrical alternans and VF.
  • To explore the role of cardiac electrical restitution in VF.
  • To identify potential antiarrhythmic targets for VF.

Main Methods:

  • Experimental and theoretical studies of cardiac tissue.
  • Analysis of spiral wave dynamics.
  • Investigating the effects of agents modulating the restitution slope.

Main Results:

  • VF initiation and break-up correlate with electrical alternans.
  • Electrical alternans are associated with a steeply sloped restitution relation.
  • Agents reducing the restitution slope suppress alternans and terminate VF.

Conclusions:

  • Electrical restitution is a potential mechanism driving VF.
  • Modulating electrical restitution may serve as a novel antiarrhythmic strategy.
  • Targeting electrical restitution offers a promising therapeutic approach for VF.

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