Department of Cardiovascular Diseases, University of Siena, Siena, Italy.
Am J Cardiol. 2013 Feb 15;111(4):595-601. doi: 10.1016/j.amjcard.2012.10.049. Epub 2012 Dec 1.
In patients with severe mitral regurgitation (MR) referred for cardiac surgery, left atrial (LA) remodeling and enlargement are accompanied by mechanical stress, mediated cellular hypertrophy, and interstitial fibrosis that finally lead to LA failure. Speckle tracking echocardiography is a novel non-Doppler-based method that allows an objective quantification of LA myocardial deformation, becoming useful for LA functional analysis. We conducted a study to evaluate the relation between the traditional and novel atrial indexes and the extent of ultrastructural alterations, obtained from patients with severe MR who were undergoing surgical correction of the valvular disease. The study population included 46 patients with severe MR, referred to our echocardiographic laboratory for a diagnostic examination before cardiac surgery. The global peak atrial longitudinal strain (PALS) was measured in all subjects by averaging all atrial segments. LA tissue samples were obtained from all patients. Masson's trichrome staining was performed to assess the extent of the fibrosis. The LA endocardial thickness was measured. A close negative correlation between the global PALS and grade of LA myocardial fibrosis was found (r = -0.82, p <0.0001), with poorer correlations for the LA indexed volume (r = 0.51, p = 0.01), LA ejection fraction (r = 0.61, p = 0.005), and E/E' ratio (0.14, p = NS). Of these indexes, global PALS showed the best diagnostic accuracy to detect LA fibrosis (area under the curve 0.89), and it appears to be a strong and independent predictor of LA fibrosis. Furthermore, we also demonstrated an inverse correlation between the global PALS and LA endocardial thickness (r = -0.66, p = 0.0001). In conclusion, in patients with severe MR referred for cardiac surgery, impairment of LA longitudinal deformation, as assessed by the global PALS, correlated strongly with the extent of LA fibrosis and remodeling.
在因严重二尖瓣反流（MR）而接受心脏手术的患者中，左心房（LA）重构和扩大伴随着机械应力、介导的细胞肥大和间质纤维化，最终导致 LA 衰竭。斑点追踪超声心动图是一种新型的非多普勒基方法，可对 LA 心肌变形进行客观定量，为 LA 功能分析提供了有用的手段。我们进行了一项研究，以评估传统和新型心房指数与超声心动图患者严重 MR 患者的超微结构改变程度之间的关系，这些患者因瓣膜疾病正在接受手术矫正。研究人群包括 46 名因严重 MR 而接受心脏手术的患者，他们在手术前在我们的超声心动图实验室进行了诊断检查。所有患者均通过测量所有心房节段的平均值来测量整体心房纵向应变（PALS）。从所有患者中获取 LA 组织样本。进行 Masson 三色染色以评估纤维化的程度。测量 LA 心内膜厚度。发现整体 PALS 与 LA 心肌纤维化程度之间存在密切的负相关（r =-0.82，p <0.0001），与 LA 指数容积（r = 0.51，p = 0.01）、LA 射血分数（r = 0.61，p = 0.005）和 E / E' 比值（0.14，p = NS）的相关性较差。在这些指标中，整体 PALS 对检测 LA 纤维化具有最佳的诊断准确性（曲线下面积 0.89），并且似乎是 LA 纤维化的强独立预测因子。此外，我们还证明了整体 PALS 与 LA 心内膜厚度之间存在反比关系（r =-0.66，p = 0.0001）。总之，在因严重 MR 而接受心脏手术的患者中，LA 纵向应变的整体 PALS 受损与 LA 纤维化和重构的程度密切相关。
