Department of Anesthesiology, University of Utah, Salt Lake City, UT.
Department of Anesthesiology, University of Utah, Salt Lake City, UT.
J Cardiothorac Vasc Anesth. 2020 Oct;34(10):2707-2717. doi: 10.1053/j.jvca.2019.11.035. Epub 2019 Dec 7.
Strain analysis allows for global and regional analysis of myocardial function and has been shown to be an independent predictor of outcomes after cardiac surgery. Strain imaging offers advantages over traditional EF measurements in that it is relatively angle independent, it is less dependent upon loading conditions, it is reproducible, it does not rely on geometric assumptions, and it can detect subclinical systolic dysfunction. Limitations of strain analysis include high temporal resolution requirements, a strong dependence on image quality, and inter-vendor variability. In addition, there is a paucity of data on the intraoperative applications of strain. The ASE has defined a global longitudinal strain of -20% measured by transthoracic echocardiography to be considered normal, with less negative values considered abnormal. Presently, there are no published guidelines on the normal values of strain with transesophageal echocardiography (TEE). However, multiple studies have shown that a reduction in intraoperative strain assessed with TEE has been shown to be an independent predictor of complications during cardiac surgery. Accordingly, further incorporation of intraoperative strain analysis with TEE could aid in prognostication for patients undergoing cardiac surgery. As perioperative strain analysis continues to advance, an understanding of these concepts is imperative for perioperative echocardiographers. It is the authors' goal to show that strain imaging can provide a reliable and objective measure that can be performed in real time to aid in decision-making and perioperative risk stratification.
应变分析可用于心肌功能的整体和局部分析，已被证明是心脏手术后结局的独立预测因素。应变成像相对于传统 EF 测量具有优势，因为它相对角度独立，对负荷条件的依赖性较小，具有可重复性，不依赖于几何假设，并且可以检测亚临床收缩功能障碍。应变分析的局限性包括高时间分辨率要求、强烈依赖于图像质量和供应商间的可变性。此外，关于术中应变的应用数据很少。美国超声心动图学会（ASE）将经胸超声心动图测量的 -20%的整体纵向应变定义为正常，负向值越低被认为越异常。目前，尚无关于经食管超声心动图（TEE）中应变正常值的公布指南。然而，多项研究表明，术中 TEE 评估的应变减少已被证明是心脏手术期间并发症的独立预测因素。因此，进一步将术中应变分析与 TEE 结合使用可能有助于预测接受心脏手术的患者的预后。随着围手术期应变分析的不断发展，围手术期超声心动图医师必须了解这些概念。作者的目标是表明应变成像可以提供可靠和客观的测量，可实时进行，以帮助决策和围手术期风险分层。
