Mechanism of Atrial Fibrillation Induced in the Left Atrial Volume-load Model

左心房容量负荷模型诱发心房颤动的机制

基本信息

批准号：
13671411
负责人：
NITTA Takashi
金额：
$ 2.24万
依托单位：
Nippon Medical School
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2003
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13671411/
关键词：
atrial fibrillation left atrium volume load pulmonary vein 電気生理高頻度刺激

项目摘要

A new experimental model for atrial fibrillation was established and serial changes in the left atrial volume and atrial electrophysiologies were examined in 10 mongrel canines. The canines underwent a left subclavian artery to pulmonary artery shunt surgery through a left thoracotomy. Left atrial rapid pacing at a cycle length of 100 ma was started 1 week after the shunt surgery.All the animals exhibited progressive dilatation of the left atrium and developed severe heart failure. Three of 10 died in the early postoperative days and 1 developed pacing failure. Remaining 6 animals were subjected to the analysis.A brief period of repetitive activations were observed after a temporal suspension of the rapid pacing one week after the pacing. The duration of repetitive activation prolonged over time and all the animals developed persistent atrial fibrillation (>10 minutes) 4 weeks after the pacing. Atrial fibrillation intervals recorded at both atrial appendages were progressively shortened and the interval in the left atrial appendage was always shorter than at the right appendage. Epicardial mapping of the persistent atrial fibrillation revealed concurrent repetitive activations arising from the right and left superior pulmonary veins that conducted toward the right atrium with progressive conduction delay.A volume load of the LA may provoke repetitive activations in the pulmonary veins and electrical remodeling of the atrial myocardium, and further facilitate the perpetuation of atrial fibrillation. This clinically relevant model of persistent AF associated with a Volume-loaded LA would be useful in examining the electrophysiology of AF and the effects of non-pharmacological therapies.

建立了一种新的用于心房颤动的实验模型，并在10个杂种犬中检查了左心房体积的串行变化和心房电生理学。犬类通过左侧胸腔切开术进行了左锁骨下动脉进行肺动脉分流手术。分流手术后1周开始以100 mA的循环长度进行左心房快速起搏。所有动物均表现出左心房的进行性扩张，并出现严重的心力衰竭。术后早期，有10人中有3人死亡，其中1例发生了节奏失败。剩下的6只动物进行了分析。在起搏后一周快速起搏后，观察到了短暂的重复激活。随着时间的推移，重复激活的持续时间延长，所有动物在起搏后4周就出现了持续的房颤（> 10分钟）。在两个心房附属处记录的心房颤动间隔逐渐缩短，左侧心房附件的间隔总是比正确的附属物短。持续性心房颤动的上性图映射揭示了由左右左上肺静脉引起的同时重复激活，该静脉向右心房进行，并进行了逐渐导致的延迟。LA的体积负载可能会引起肺静脉和肺部静脉内部静脉内的重塑，并进一步构思的静脉静脉和电气。这种与体积加载的LA相关的临床相关模型对于检查AF的电生理学和非药物疗法的作用将很有用。