Department of Cardiology, Gifu Prefectural General Medical Center, Gifu, Japan.
Eur Heart J Cardiovasc Imaging. 2012 Mar;13(3):227-34. doi: 10.1093/ejechocard/jer281. Epub 2011 Dec 13.
Left atrial volume (LAV) has been proposed as a predictor of atrial fibrillation (AF) and LA function has been investigated by velocity vector imaging (VVI) echocardiography. The aim of this study was to determine whether LA function was associated with the existence of AF.
We examined emptying function (EF) as a global function and strain rate (SR) as a regional function of LA function during three phases of the cardiac cycle (reservoir, conduit, and booster pump phase). The parameters were measured (apical four-chamber view) by VVI in 302 subjects [126 sinus rhythm, 91 paroxysmal AF (PAF), and 85 chronic AF]. Global and regional LA function were significantly lower in PAF patients during sinus rhythm (LA total EF: 35 ± 8%; SR at atrial contraction: -0.8 ± 0.3s(-1)) and much lower in chronic AF patients (LA total EF 22 ± 8%) than in subjects with sinus rhythm (LA total EF: 47 ± 7%; SR at atrial contraction: -1.4 ± 0.4s(-1)). In multivariate logistic regression analysis, LA active EF and SR at atrial contraction were independent features of PAF.
LA function, particularly LA active relaxation and contraction, was lower in PAF patients than in subjects with sinus rhythm, regardless of LA size and age. LA functional impairment was observed regardless of hypertension before LA enlargement in patients with PAF. Reduced LA function, as assessed by VVI, is an important feature of AF as well as LA structure.
左心房容积（LAV）已被提出作为心房颤动（AF）的预测因子，并且已经通过速度向量成像（VVI）超声心动图研究了左心房功能。本研究的目的是确定左心房功能是否与 AF 的存在有关。
我们检查了排空功能（EF）作为左心房功能的整体功能和应变率（SR）作为局部功能，在心脏周期的三个阶段（储器、导管和助推泵阶段）。通过 VVI 在 302 例受试者（126 例窦性节律、91 例阵发性 AF（PAF）和 85 例慢性 AF）中测量参数（心尖四腔视图）。在窦性节律时，PAF 患者的整体和局部左心房功能明显降低（左心房总 EF：35 ± 8%；心房收缩时的 SR：-0.8 ± 0.3s(-1)），而慢性 AF 患者的左心房总 EF 则明显降低（左心房总 EF：22 ± 8%）（窦性节律时的左心房总 EF：47 ± 7%；心房收缩时的 SR：-1.4 ± 0.4s(-1)）。在多变量逻辑回归分析中，左心房主动 EF 和心房收缩时的 SR 是 PAF 的独立特征。
无论左心房大小和年龄如何，PAF 患者的左心房功能，特别是左心房主动松弛和收缩功能，均低于窦性节律患者。在 PAF 患者左心房扩大之前，无论是否存在高血压，均可观察到左心房功能障碍。通过 VVI 评估的左心房功能降低是 AF 以及左心房结构的重要特征。
