Abstract | BACKGROUND: METHODS AND RESULTS:
Amiodarone (n=7, 40 mg. kg(-1). d(-1)) and dronedarone (n=8, 20 mg/kg BID) were started at 6 weeks of CAVB (baseline). Six dogs served as controls. Surface ECGs and endocardially placed monophasic action potential catheters in the left (LV) and right (RV) ventricles were recorded to assess QTc time, action potential duration (APD), interventricular dispersion (DeltaAPD=LV APD minus RV APD), early afterdepolarizations (EADs), ectopic beats, and TdP. Both amiodarone (+21%) and dronedarone (+31%) increased QTc time. Amiodarone showed no increase in DeltaAPD in 4 of 7 dogs, whereas dronedarone augmented DeltaAPD in 7 of 8 animals. After dronedarone, TdP occurred in 4 of 8 dogs with the highest DeltaAPD (105+/-20 ms). TdP was never seen with amiodarone, not even in the dogs that had DeltaAPD values comparable to those with dronedarone. Furthermore, a difference existed in EADs and ectopic activity incidence ( dronedarone 3 of 8; amiodarone 0 of 7), which was also seen during an epinephrine challenge. CONCLUSIONS:
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Authors | J M van Opstal, M Schoenmakers, S C Verduyn, S H de Groot, J D Leunissen, F F van Der Hulst, M M Molenschot, H J Wellens, M A Vos |
Journal | Circulation
(Circulation)
Vol. 104
Issue 22
Pg. 2722-7
(Nov 27 2001)
ISSN: 1524-4539 [Electronic] United States |
PMID | 11723026
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Anti-Arrhythmia Agents
- Vasoconstrictor Agents
- Dronedarone
- Amiodarone
- Epinephrine
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Topics |
- Action Potentials
(drug effects)
- Administration, Oral
- Amiodarone
(administration & dosage, adverse effects, analogs & derivatives, metabolism)
- Anesthesia
- Animals
- Anti-Arrhythmia Agents
(administration & dosage)
- Arrhythmias, Cardiac
(chemically induced, physiopathology)
- Cardiac Catheterization
- Disease Models, Animal
- Dogs
- Dronedarone
- Electrocardiography
- Electrophysiologic Techniques, Cardiac
- Epinephrine
(pharmacology)
- Female
- Heart Block
(complications, drug therapy, physiopathology)
- Hemodynamics
(drug effects)
- Long QT Syndrome
(complications, drug therapy, physiopathology)
- Male
- Myocardium
(chemistry, metabolism)
- Organ Size
(drug effects)
- Torsades de Pointes
(chemically induced, physiopathology, prevention & control)
- Vasoconstrictor Agents
(pharmacology)
- Wakefulness
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