Voigt Jens-Uwe, Exner Bert, Schmiedehausen Kristin, Huchzermeyer Cord, Reulbach Udo, Nixdorff Uwe, Platsch Günther, Kuwert Torsten, Daniel Werner G, Flachskampf Frank A
Medizinische Klinik II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany.
Circulation. 2003 Apr 29;107(16):2120-6. doi: 10.1161/01.CIR.0000065249.69988.AA. Epub 2003 Apr 7.
Interpretation of dobutamine stress echocardiography (DSE) is subjective and strongly dependent on the skills of the reader. Strain-rate imaging (SRI) by tissue Doppler may objectively analyze regional myocardial function. This study investigated SRI markers of stress-induced ischemia and analyzed their applicability in a clinical setting.
DSE was performed in 44 patients with known or suspected coronary artery disease. Simultaneous perfusion scintigraphy served as a "gold standard" to define regional ischemia. All patients underwent coronary angiography. Segmental strain and strain rate were analyzed at all stress levels by measuring amplitude and timing of deformation and visual curved M-mode analysis. Results were compared with conventional stress echo reading. In nonischemic segments, peak systolic strain rate increased significantly with dobutamine stress (-1.6+/-0.6 s-1 versus -3.4+/-1.4 s-1, P<0.01), whereas strain during ejection time changed only minimally (-17+/-6% versus -16+/-9%, P<0.05). During DSE, 47 myocardial segments in 19 patients developed scintigraphy-proven ischemia. Strain-rate increase (-1.6+/-0.8 s-1 versus -2.0+/-1.1 s-1, P<0.05) and strain (-16+/-7% versus -10+/-8%, P<0.05) were significantly reduced (both P<0.01 compared with nonischemic). Postsystolic shortening (PSS) was found in all ischemic segments. The ratio of PSS to maximal segmental deformation was the best quantitative parameter to identify stress-induced ischemia. Compared with conventional readings, SRI curved M-mode assessment improved sensitivity/specificity from 81%/82% to 86%/90%.
During DSE, SRI quantitatively and qualitatively differentiates ischemic and nonischemic regional myocardial response to dobutamine stress. The ratio of PSS to maximal strain may be used as an objective marker of ischemia during DSE.
多巴酚丁胺负荷超声心动图（DSE）的解读具有主观性，且很大程度上依赖于读者的技能。组织多普勒应变率成像（SRI）可客观分析局部心肌功能。本研究调查了应激性心肌缺血的SRI标志物，并分析了其在临床环境中的适用性。
对44例已知或疑似冠心病患者进行了DSE检查。同步灌注闪烁扫描作为定义局部缺血的“金标准”。所有患者均接受了冠状动脉造影。通过测量变形的幅度和时间以及视觉曲线M型分析，在所有应激水平下分析节段应变和应变率。将结果与传统的负荷超声心动图解读进行比较。在非缺血节段，多巴酚丁胺负荷时收缩期峰值应变率显著增加（-1.6±0.6 s-1对-3.4±1.4 s-1，P<0.01），而射血期应变仅略有变化（-17±6%对-16±9%，P<0.05）。在DSE期间，19例患者的47个心肌节段出现了闪烁扫描证实的缺血。应变率增加（-1.6±0.8 s-1对-2.0±1.1 s-1，P<0.05）和应变（-16±7%对-10±8%，P<0.05）均显著降低（与非缺血节段相比，两者P<0.01）。在所有缺血节段均发现了收缩后缩短（PSS）。PSS与最大节段变形的比值是识别应激性心肌缺血的最佳定量参数。与传统解读相比，SRI曲线M型评估将敏感性/特异性从81%/82%提高到了86%/90%。
在DSE期间，SRI在定量和定性方面区分了缺血和非缺血局部心肌对多巴酚丁胺应激的反应。PSS与最大应变的比值可作为DSE期间心肌缺血的客观标志物。
