Left atrial myocardial extension onto pulmonary veins in humans: Anatomic observations relevant for atrial arrhythmias
Left atrial myocardial extension onto pulmonary veins in humans: Anatomic observations relevant for atrial arrhythmias
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DOI：
10.1111/j.1540-8167.2000.tb00068.x
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发表时间：
2000-08-01
影响因子：
2.7
通讯作者：
Becker, AE
中科院分区：
文献类型：
--
作者：
Saito, T;Waki, K;Becker, AE
导读：电生理学研究表明，由异位搏动引起的心房颤动（AF）可能起源于肺静脉。左房心肌的延伸被认为起作用，但很少有详细的解剖信息，特别是在人类中。方法与结果：对39例人体解剖心脏进行研究；22例房颤，17例无心房心律失常。解剖左房壁及肺静脉肌纤维分布。18例心脏显微镜下观察心肌袖；在5个心脏中，进行了心肌套管纤维排列的三维重建。在检查的99条肺静脉中，96条含有心肌套管。上肺静脉套管长度最大（P < 0.01）。均匀和非均匀肌纤维排列之间没有统计学上的显著差异。显微镜检查显示心肌套管位于肺静脉外膜侧，被纤维脂肪组织平面与肌肉介质隔开。心肌袖的最远端区纤维化增加，小群心肌细胞被包封，最终纤维组织内萎缩细胞完全消失。未遇到节点状结构。结论：观察到心肌袖周区与心肌肌群间结缔组织沉积增加有关，提示退行性改变，从组织学角度来看，与进行性缺血相吻合，这些变化可能为心房微再入提供了基础，从而为心房心律失常提供了基础。
Introduction: Electrophysiologic studies have shown that spontaneous initiation of atrial fibrillation (AF) by ectopic beats may originate from within pulmonary veins. The extensions of left atrial myocardium are considered to play a role, but there is little detailed anatomic information available, particularly in humans.Methods and Results: Thirty-nine human autopsy hearts were studied; 22 with AF and 17 without atrial arrhythmias. The muscle fiber arrangement of the left atrial wall and pulmonary veins was dissected. In 18 hearts, myocardial sleeves were studied microscopically; in five hearts, three-dimensional reconstruction of the fiber arrangement in the myocardial sleeves was performed. Of 99 pulmonary veins examined, 96 contained a myocardial sleeve. The length of the sleeves was largest in the superior pulmonary veins (P < 0.01). There mere no statistically significant differences between uniform and nonuniform muscle fiber arrangements. Microscopic evaluation revealed myocardial sleeves positioned on the adventitial side of the pulmonary vein, separated from the muscular media by a fibrofatty tissue plane. The most distal zone of the myocardial sleeves showed increasing fibrosis with encapsulation of small groups of myocardial cells and eventually with total disappearance of atrophic cells within fibrous tissue. Node-like structures were not encountered. There was no relationship with presence or absence of AF.Conclusion: The observation that the peripheral zones of myocardial sleeves are associated with increasing connective tissue deposition between myocardial muscle groups suggests a degenerative change that, from the histologic viewpoint, fits with progressive ischemia, These changes could provide a basis for microreentry and, hence, for atrial arrhythmias.