López-Candales Angel
Division of Cardiovascular Diseases, University of Cincinnati College of Medicine, Cincinnati, Ohio.
Echocardiography. 2014 May;31(5):605-14. doi: 10.1111/echo.12441. Epub 2013 Nov 26.
Increased left ventricular (LV) mass is a well-known independent predictor of cardiovascular morbidity and mortality. Even though these patients have an increased risk of LV diastolic dysfunction; recent data have suggested the presence of subtle LV systolic abnormalities. This study sought to demonstrate if a novel speckle tracking automated functional imaging (AFI) tool would be useful in identifying differences in strain generation between patients with normal and increased LV wall mass.
Standard measures of LV systolic and diastolic function were collected from 90 patients divided into Group I with LV mass index < 100 g/m(2) and Group II with LV mass index values ≥ 100 g/m(2). AFI was also obtained to measure peak global LV myocardial strain.
As expected, patients with an increased LV mass index had significant LV diastolic abnormalities. However, in addition these patients in Group II not only had significantly lower peak systolic strain values but also significantly lower mitral annular plane systolic excursion (MAPSE) and MA tissue Doppler imaging systolic velocity values than patients in Group I despite having comparable estimates of LV ejection fraction, based on the Simpson's method.
Based on these results, AFI provides prompt point of care information regarding LV function and mechanics and identifies differences in longitudinal strain generation between patients with normal and increased LV wall mass. Additional studies are now required to prospectively determine if AFI measures of LV function might be useful to identify patients with an increased LV mass that will develop symptomatic systolic or diastolic heart failure.
左心室(LV)质量增加是心血管疾病发病率和死亡率的一个众所周知的独立预测因素。尽管这些患者发生左心室舒张功能障碍的风险增加,但最近的数据表明存在细微的左心室收缩异常。本研究旨在证明一种新型斑点追踪自动功能成像(AFI)工具是否有助于识别正常和左心室壁质量增加患者之间应变产生的差异。
从90例患者中收集左心室收缩和舒张功能的标准测量值,这些患者分为两组,第一组左心室质量指数<100 g/m²,第二组左心室质量指数≥100 g/m²。还获得了AFI测量左心室整体心肌峰值应变。
正如预期的那样,左心室质量指数增加的患者存在明显的左心室舒张异常。然而,此外,尽管根据辛普森法两组患者的左心室射血分数估计值相当,但第二组患者不仅收缩期峰值应变值显著低于第一组患者,而且二尖瓣环平面收缩期位移(MAPSE)和二尖瓣环组织多普勒成像收缩期速度值也显著低于第一组患者。
基于这些结果,AFI提供了关于左心室功能和力学的即时床旁信息,并识别了正常和左心室壁质量增加患者之间纵向应变产生的差异。现在需要进一步的研究来前瞻性地确定AFI测量的左心室功能是否有助于识别左心室质量增加且将发展为有症状的收缩性或舒张性心力衰竭的患者。