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Fatal arrhythmias: Another reason why doctors remain cautious about chloroquine/hydroxychloroquine for treating

Ilija Uzelac1, Shahriar Iravanian2, Hiroshi Ashikaga3

  • 1School of Physics, Georgia Institute of Technology, Atlanta, Georgia.

Heart Rhythm
|June 2, 2020
PubMed

Insights

Hydroxychloroquine (HCQ) can cause dangerous heart rhythm problems. This study found HCQ increases action potential dispersion and triggers ventricular tachycardia, highlighting its proarrhythmic effects.

Area of Science:

  • Cardiovascular pharmacology
  • Electrophysiology
  • Drug safety

Background:

  • Hydroxychloroquine (HCQ) was widely investigated for COVID-19 treatment.
  • Concerns exist regarding HCQ's effectiveness and proarrhythmic potential, particularly QT prolongation.

Purpose of the Study:

  • To investigate the specific arrhythmic effects of HCQ.
  • To assess HCQ's cardiac risks in a population (COVID-19 patients) already prone to arrhythmias.

Main Methods:

  • Utilized optical mapping with voltage-sensitive dyes.
  • Examined ex vivo guinea pig and rabbit hearts.
  • Perfused hearts with the upper therapeutic serum dose of HCQ (1000 ng/mL).

Main Results:

  • HCQ significantly increased action potential dispersion.
  • Repolarization alternans were observed.
  • Polymorphic ventricular tachycardia was initiated by HCQ.

Conclusions:

  • The study confirms the proarrhythmic effects of hydroxychloroquine.
  • Findings underscore the cardiac risks associated with HCQ use.
Abstract

Keywords:
Action potential duration dispersionArrhythmiasExperimental optical mappingHydroxychloroquineLong QT syndromeT-wave alternans

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