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| Format: | Artículo científico |
| Language: | en |
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Universidad del Valle
2008
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| Online Access: | https://www.redalyc.org/articulo.oa?id=28339304 |
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Table of Contents:
- Conduction between left superior pulmonary vein and left atria and atria fibrillation under cervical vagal trunk stimulation Hou Yuemei Zhang Xiaoqin Song Jianguo Na Jina Medicina Left atria Atria fibrillation Cervical vagal trunk Electrical conduction Left superior pulmonary Objective: The effect of cervical vagal trunk stimulation on conduction between left superior pulmonary vein and left atriaand atria fibrillation have not been systematically studied. We attempted to investigate the electrical conduction between LAand LSPV in dogs with cervical vagal trunk stimulation and evaluate the possible underline substrates for local reentry andinitiation and maintenance of AF.Methods: 12 mongrel dogs (18-25 kg) underwent cervical vagal trunk stimulation at high-frequency (60 ms, 1-4V) to producesinus arrest lasting >2 seconds,complete atrioventricular AV blocking or the sinus rate decreasing more than 50%. Left lateralthoracotomy was performed and the heart was exposed in a pericardial cradle. The HRA, LAA, PV-LAJ, LSPVm and LSPVdwas locally stimulated (100 ms, 2-8V). ERP of HRA, LAA, PV-LAJ and within LSPV, ERP heterogeneity within LSPV andconduction between left superior pulmonary vein and left atria and atrial fibrillation inducing rate with vagal response wasanalyzed.Results: 1. During cervical vagal stimulation, the heart rate was reduced significantly from baseline 156±34 bpm to 75±34bpm (p<0.05, n=12), ERP of HRA, LAA, PV-LAJ, LSPVm and LSPVd sites was shortened locally in all animals, ERP heterogeneity(COV-ERP ) was increased from baseline 3±3% to 30±13% (on average, p<0.05; n=12) and inducibility of AF wasincreased from baseline 49.9% to 70.9% with S1S1stimulation (100 ms, 2-8V) and from baseline 3.7% to 43.5% with S1S2 (5 msdecremented stepwise S1S2 300/200 ms, 2-8V, n=12; 2. LA and PV potentials at LA, PV-LAJ, LSPVm and LSPVd was overlappedduring sinus rate and separated remarkably by stimulating at distal part of LSPV (n=9); 3. Unidirectional and bi-directionalconduction(n=9), bi-directional decremented conduction (n=6), delayed conduction from LSPVp to LSPVd (n=12) and slowconduction from stimulating signal to local tissue potential (n=9) before onset of AF were recorded by pacing from both LSPVand LA.Conclusion: Our study strongly suggested that fast ectopic beating, abnormal vagal nerve activation as well as remodelingconduction between left superior pulmonary vein and left atria might are the common underline substrates for local reentryand AF initiation and maintenance. 2008 artículo científico 0120-8322 https://www.redalyc.org/articulo.oa?id=28339304 en http://www.redalyc.org/revista.oa?id=283 Colombia Médica application/pdf Universidad del Valle Colombia Médica (Colombia) Num.3 Vol.39