D'Andrea Antonello, Caso Pio, Romano Silvio, Scarafile Raffaella, Cuomo Sergio, Salerno Gemma, Riegler Lucia, Limongelli Giuseppe, Di Salvo Giovanni, Romano Massimo, Liccardo Biagio, Iengo Raffaele, Ascione Luigi, Del Viscovo Luca, Calabrò Paolo, Calabrò Raffaele
Second University of Naples, Italy.
Int J Cardiol. 2009 Mar 6;132(3):354-63. doi: 10.1016/j.ijcard.2007.11.102. Epub 2008 Feb 5.
In patients with idiopathic dilated cardiomyopathy (DCM) a more depressed left atrial (LA) booster pump function has been observed compared to ischemic patients although under similar loading conditions, and attributed both to altered LA overload and to LA larger involvement in the myopathic process.
To detect by speckle-tracking two-dimensional strain (2DSE) LA systolic dysfunction in patients with either idiopathic or ischemic DCM, and to assess in these patients possible correlation between LA myocardial function and exercise capacity during cardiopulmonary test.
Three-hundred-fourteen patients (52.4+/-11.2 years) with either idiopathic (160 patients) or ischemic (154 patients) DCM underwent cardiopulmonary stress test, standard Doppler echo and 2DSE analysis of atrial longitudinal strain in the basal segments of LA septum and LA lateral wall, and in LA roof.
The two groups were comparable for most of clinical variables. LV volumes, ejection fraction, stroke volume, and mitral valve effective regurgitant orifice were similar between the two groups. No significant differences were evidenced in Doppler transmitral inflow measurements. Also LA diameter and maximal volume were similar between the two groups. Conversely, LA active empting volume and fraction were both lower in patients with idiopathic DCM (<0.001). Peak systolic myocardial atrial strain was significantly reduced in patients with idiopathic DCM compared with ischemic DCM at the level of all the analyzed atrial segments (p<0.0001). By multivariable analysis, in the overall population, ischemic aetiology of DCM (p<0.0001) and LA volume (p<0.001) were the only independent determinants of LA lateral wall systolic strain. On the other hand, LA lateral wall systolic strain (p<0.0001) and LA volume (p<0.001) were powerful independent predictors of peak oxygen consumption during cardiopulmonary exercise testing.
Two-dimensional strain represents a promising non-invasive technique to assess LA atrial myocardial function in patients with DCM. LA systolic deformation is more depressed in idiopathic compared with ischemic DCM, and is closely associated with functional capacity during effort. Future longitudinal studies are warranted to further our understanding of the natural history of LA myocardial function, the extent of reversibility of LA dysfunction with therapy, and the possible prognostic impact of such indexes in patients with congestive heart failure.
在特发性扩张型心肌病（DCM）患者中，尽管处于相似的负荷条件下，但与缺血性心肌病患者相比，已观察到左心房（LA）辅助泵功能更为低下，这归因于LA负荷改变以及LA在肌病过程中更大程度的受累。
通过斑点追踪二维应变（2DSE）检测特发性或缺血性DCM患者的LA收缩功能障碍，并评估这些患者LA心肌功能与心肺试验期间运动能力之间的可能相关性。
314例患者（年龄52.4±11.2岁），其中特发性DCM患者160例，缺血性DCM患者154例，均接受了心肺应激试验、标准多普勒超声心动图检查以及对LA间隔基底段、LA侧壁基底段和LA顶部的心房纵向应变进行2DSE分析。
两组在大多数临床变量方面具有可比性。两组间左心室容积、射血分数、每搏量以及二尖瓣有效反流口面积相似。多普勒二尖瓣血流测量未发现显著差异。两组间LA直径和最大容积也相似。相反，特发性DCM患者的LA主动排空容积和分数均较低（<0.001）。在所有分析的心房节段水平，特发性DCM患者的收缩期心肌心房峰值应变与缺血性DCM患者相比显著降低（p<0.0001）。通过多变量分析，在总体人群中，DCM的缺血病因（p<0.0001）和LA容积（p<0.001）是LA侧壁收缩期应变的仅有的独立决定因素。另一方面，LA侧壁收缩期应变（p<0.0001）和LA容积（p<0.001）是心肺运动试验期间峰值耗氧量的有力独立预测因素。
二维应变是评估DCM患者LA心房心肌功能的一种有前景的非侵入性技术。与缺血性DCM相比，特发性DCM患者的LA收缩变形更为低下，且与运动期间的功能能力密切相关。未来有必要进行纵向研究，以进一步了解LA心肌功能的自然病史、LA功能障碍经治疗后的可逆程度以及这些指标对充血性心力衰竭患者可能的预后影响。
