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Amiodarone attenuates the proarrhythmic effects of dobutamine in patients with advanced congestive heart failure

Eleftheria P Tsagalou1, Pantelis Gounopoulos, John V Terrovitis

  • 13rd Cardiology Department, University of Athens School of Medicine, Athens, Greece.

Hellenic Journal of Cardiology : HJC = Hellenike Kardiologike Epitheorese
|May 26, 2009
PubMed

Insights

Oral amiodarone reduces dobutamine-induced arrhythmias in advanced heart failure patients. This combination therapy enhances the safety of intermittent dobutamine infusions for congestive heart failure management.

Area of Science:

  • Cardiology
  • Pharmacology

Background:

  • Long-term positive inotropic drugs in end-stage congestive heart failure (CHF) are linked to increased mortality due to proarrhythmia.
  • Oral amiodarone with intermittent dobutamine infusions (IDI) has demonstrated improved survival rates in CHF patients.

Purpose of the Study:

  • To evaluate the antiarrhythmic effects of oral amiodarone on dobutamine-induced arrhythmias in advanced CHF patients.
  • To assess the safety of combining oral amiodarone with IDI in this patient population.

Main Methods:

  • Thirty advanced CHF patients (NYHA class III-IV) received oral amiodarone (400 mg/day) for one month prior to weekly 8-hour dobutamine infusions (10 µg/kg/min).
  • 24-hour ambulatory electrocardiograms were recorded before and during dobutamine infusions to monitor cardiac rhythm and arrhythmias.

Main Results:

  • Dobutamine infusions did not significantly alter average heart rate (72 bpm pre vs. 72 bpm during IDI).
  • No significant increase in premature ventricular complexes, ventricular couplets, or non-sustained ventricular tachycardia was observed.
  • No instances of ventricular fibrillation or sustained ventricular tachycardia occurred during or after IDI.

Conclusions:

  • Chronic low-dose oral amiodarone effectively attenuates the proarrhythmic potential of dobutamine.
  • This combination therapy improves the safety profile of ambulatory intermittent dobutamine infusions for advanced congestive heart failure patients.
Abstract

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