Arrhythmogenesis after acute myocardial necrosis with and without preceding ischemia in rats
| Autor: | Zenon S. Kyriakides, Apostolos Papalois, Marianthi Kontonika, Mesele-Christina Valenti, Agapi D. Vilaeti, Giannis Baltogiannis, Theofilos M. Kolettis |
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| Rok vydání: | 2014 |
| Předmět: |
Male
medicine.medical_specialty Physiology Myocardial Infarction Ischemia Infarction Myocardial Reperfusion Injury Ventricular tachycardia Severity of Illness Index Electrocardiography Necrosis Ventricular Dysfunction Left Heart Rate Internal medicine Drug Discovery medicine Animals cardiovascular diseases Myocardial infarction Rats Wistar Pharmacology business.industry Myocardium Electrocardiography in myocardial infarction Arrhythmias Cardiac General Medicine medicine.disease Disease Models Animal Coagulative necrosis Ventricular fibrillation cardiovascular system Cardiology Myocardial infarction complications business |
| Zdroj: | Journal of Basic and Clinical Physiology and Pharmacology. 25 |
| ISSN: | 2191-0286 0792-6855 |
| DOI: | 10.1515/jbcpp-2013-0117 |
| Popis: | Background The relative role of acute myocardial ischemia and infarction in ventricular arrhythmogenesis is incompletely understood. We compared the arrhythmia pattern after ischemia/infarction to that observed after direct myocardial necrosis without preceding ischemia in rats. Methods Coagulation necrosis was induced in Wistar rats (n=20, 280±3 g) by radiofrequency current application (for 15 s) from a 4-mm-tip ablation catheter. Myocardial infarction was induced by coronary artery ligation with (n=10) or without (n=10) reperfusion. Using 24-h telemetry recording, we examined ventricular arrhythmias, voluntary motor activity and indices of sympathetic activation. Results The coagulation-necrosis volume was 24.4%±0.6%, comparable to the infarct size in the absence of reperfusion. Acute left ventricular failure and sympathetic activation were similar in the three groups. Coagulation necrosis induced ventricular fibrillation immediately, followed by a second peak after ∼1 h. Reperfusion decreased ventricular arrhythmias, whereas a second arrhythmogenic period (between the third and the eight hour) was noted in non-reperfused infarcts (mainly monomorphic ventricular tachycardia). Conclusions Distinct arrhythmia patterns occur after myocardial infarction (with or without reperfusion) and after direct necrosis. They are not produced by differences in sympathetic activation and are likely related to the evolution of myocardial injury. The necrosis rat model may be useful in studies of arrhythmogenesis. |
| Databáze: | OpenAIRE |
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