Abstract | BACKGROUND: METHODS AND RESULTS: Electrophysiological study and epicardial mapping were performed before and after rotigaptide administration in dogs with ATP and congestive heart failure, as well as in similarly instrumented sham dogs that were not tachypaced. For atrial myocardial ischemia, dogs administered rotigaptide before myocardial ischemia were compared with no- drug myocardial ischemia controls. ATP significantly shortened the atrial effective refractory period (P=0.003) and increased AF duration (P=0.008), with AF lasting >3 hours in all 6-week ATP animals. Rotigaptide increased conduction velocity in ATP dogs slightly but significantly (P=0.04) and did not affect the effective refractory period, AF duration, or atrial vulnerability. In dogs with congestive heart failure, rotigaptide also slightly increased conduction velocity (P=0.046) but failed to prevent AF promotion. Rotigaptide had no statistically significant effects in sham dogs. Myocardial ischemia alone increased AF duration and impaired conduction (based on conduction velocity across the ischemic border and indices of conduction heterogeneity). Rotigaptide prevented myocardial ischemia-induced conduction slowing and AF duration increases. CONCLUSIONS:
Rotigaptide improves conduction in various AF models but suppresses AF only for the acute ischemia substrate. These results define the atrial antiarrhythmic profile of a mechanistically novel antiarrhythmic drug and suggest that gap junction dysfunction may be more important in ischemic AF than in ATP remodeling or congestive heart failure substrates.
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Authors | Akiko Shiroshita-Takeshita, Masao Sakabe, Ketil Haugan, James K Hennan, Stanley Nattel |
Journal | Circulation
(Circulation)
Vol. 115
Issue 3
Pg. 310-8
(Jan 23 2007)
ISSN: 1524-4539 [Electronic] United States |
PMID | 17224477
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Anti-Arrhythmia Agents
- Oligopeptides
- rotigaptide
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Topics |
- Animals
- Anti-Arrhythmia Agents
(blood, pharmacology, therapeutic use)
- Atrial Fibrillation
(physiopathology, prevention & control)
- Disease Models, Animal
- Dogs
- Electrocardiography
- Electrophysiology
- Gap Junctions
(drug effects, physiology)
- Heart Conduction System
(drug effects, physiology)
- Heart Failure
(physiopathology)
- Myocardial Ischemia
(physiopathology)
- Oligopeptides
(blood, pharmacology, therapeutic use)
- Tachycardia, Ectopic Atrial
(physiopathology)
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