Badran Hala Mahfouz, Soltan Ghada, Hassan Hesham, Nazmy Ahmed, Faheem Naglaa, Saadan Haythem, Yacoub Magdi H
Cardiology Department, Menoufiya University, Egypt.
Glob Cardiol Sci Pract. 2013 Nov 1;2012(2):67-80. doi: 10.5339/gcsp.2012.25. eCollection 2012.
Hypertrophic cardiomyopathy (HCM) represents a generalized myopathic process affecting both ventricular and atrial myocardium. We assessed the global and regional left atrial (LA) function and its relation to left ventricular (LV) mechanics and clinical status in patients with HCM using Vector Velocity Imaging (VVI).
VVI of the LA and LV was acquired from apical four- and two-chamber views of 108 HCM patients (age 40 ± 19years, 56.5% men) and 33 healthy subjects, all had normal LV systolic function. The LA subendocardium was traced to obtain atrial volumes, ejection fraction, velocities, and strain (ϵ)/strain rate (SR) measurements.
Left atrial reservoir (ϵsys,SRsys) and conduit (early diastolic SRe) function were significantly reduced in HCM compared to controls (P < .0001). Left atrial deformation directly correlated to LVϵsys, SRsys and negatively correlated to age, NYHA class, left ventricular outflow tract (LVOT) gradient, left ventricular mass index (LVMI), LA volume index and severity of mitral regurge (P < 0.001). Receiver operating characterist was constructed to explore the cutoff value of LA deformation in differentiation of LA dysfunction; ϵsys < 40% was 75% sensitive, 50% specific, SRsys < 1.7s(- 1) was 70% sensitive, 61% specific, SRe> - 1.8s(- 1) was 81% sensitive and 30% specific, SRa> - 1.5s(- 1) was 73% sensitive and 40% specific. By multivariate analysis global LVϵsys and LV septal thickness are independent predictors for LAϵsys, while end systolic diameter is the only independent predictor for SRsys, P < .001.
Left atrial reservoir and conduit function as measured by VVI were significantly impaired while contractile function was preserved among HCM patients. Left atrial deformation was greatly influenced by LV mechanics and correlated to severity of phenotype.
肥厚型心肌病（HCM）是一种影响心室和心房心肌的全身性肌病过程。我们使用向量速度成像（VVI）评估了HCM患者的左心房（LA）整体和局部功能及其与左心室（LV）力学和临床状态的关系。
从108例HCM患者（年龄40±19岁，男性占56.5%）和33例健康受试者的心尖四腔和两腔视图中获取LA和LV的VVI，所有受试者左心室收缩功能均正常。追踪LA心内膜下区域以获得心房容积、射血分数、速度和应变（ϵ）/应变率（SR）测量值。
与对照组相比，HCM患者的左心房储存功能（ϵsys，SRsys）和管道功能（舒张早期SRe）显著降低（P <.0001）。左心房变形与LVϵsys、SRsys直接相关，与年龄、纽约心脏协会（NYHA）分级、左心室流出道（LVOT）梯度、左心室质量指数（LVMI）、LA容积指数和二尖瓣反流严重程度呈负相关（P < 0.001）。构建受试者工作特征曲线以探索LA变形在区分LA功能障碍中的临界值；ϵsys < 40%时敏感性为75%，特异性为50%；SRsys < 1.7s(-1)时敏感性为70%，特异性为61%；SRe > -1.8s(-1)时敏感性为81%，特异性为30%；SRa > -1.5s(-1)时敏感性为73%，特异性为40%。通过多变量分析，整体LVϵsys和LV室间隔厚度是LAϵsys的独立预测因子，而收缩末期直径是SRsys的唯一独立预测因子，P <.001。
通过VVI测量，HCM患者的左心房储存和管道功能显著受损，而收缩功能得以保留。左心房变形受LV力学的显著影响，并与表型严重程度相关。
