Arita Takeshi, Sorescu George P, Schuler Brian T, Schmarkey Laura S, Merlino John D, Vinten-Johansen Jakob, Leon Angel R, Martin Randolph P, Sorescu Dan
Division of Cardiology, Emory University School of Medicine, 1639 Pierce Drive, Atlanta, GA 30322, USA.
Am J Physiol Heart Circ Physiol. 2007 Jul;293(1):H735-42. doi: 10.1152/ajpheart.00168.2007. Epub 2007 Apr 20.
Multiple echocardiographic criteria have been proposed to diagnose mechanical dyssynchrony in patients with heart failure without being validated against a model of cardiac dyssynchrony with heart failure. This study examines which of these methods can detect dyssynchrony in a canine model. Adult mongrel dogs underwent His-bundle ablation and right-ventricular pacing for 4 wk at either 110 bpm to induce dyssynchrony without heart failure (D group, n = 12) or 170 bpm to induce dyssynchrony with heart failure (DHF group, n = 9). To induce heart failure with narrow QRS, atria were paced at 190 bpm for 4 wk (HF group, n = 8). Tissue Doppler imaging (TDI) and two-dimensional echocardiography were performed at baseline and at end of study. Standard deviation of time to peak systolic velocity (color-coded TDI), time to peak S wave on pulse-wave TDI, time to peak radial and circumferential strain by speckle-tracking analysis (E(rr) and E(cc), respectively), and septal-to-posterior wall motion delay on M mode were obtained. In D group, only E(rr) and E(cc) were increased by dyssynchrony. In contrast, all the echocardiographic parameters of dyssynchrony appeared significantly augmented in the DHF group. Receiver-operator curve analysis showed good sensitivity of E(rr) (90%) and E(cc) (100%) to detected dyssynchrony without heart failure and excellent sensitivity and specificity of E(rr) and E(cc) to detect dyssynchrony with heart failure. Radial strain by speckle tracking is more accurate than TDI velocity to detect cardiac dyssynchrony in a canine model of dyssynchrony with or without heart failure.
已经提出了多种超声心动图标准来诊断心力衰竭患者的机械性不同步，但尚未与心力衰竭心脏不同步模型进行验证。本研究探讨了这些方法中的哪一种能够在犬模型中检测到不同步。成年杂种犬接受希氏束消融和右心室起搏4周，起搏频率为110次/分钟以诱导无心力衰竭的不同步（D组，n = 12）或170次/分钟以诱导伴有心力衰竭的不同步（DHF组，n = 9）。为了在窄QRS波时诱导心力衰竭，心房以190次/分钟的频率起搏4周（HF组，n = 8）。在基线和研究结束时进行组织多普勒成像（TDI）和二维超声心动图检查。获得收缩期峰值速度时间的标准差（彩色编码TDI）、脉冲波TDI上S波峰值时间、斑点追踪分析得出的径向和圆周应变峰值时间（分别为E(rr)和E(cc)）以及M型上的室间隔至后壁运动延迟。在D组中，只有E(rr)和E(cc)因不同步而增加。相比之下，DHF组中所有不同步的超声心动图参数均显著增加。受试者工作特征曲线分析显示，E(rr)（90%）和E(cc)（100%）对检测无心力衰竭的不同步具有良好的敏感性，而E(rr)和E(cc)对检测伴有心力衰竭的不同步具有出色的敏感性和特异性。在伴有或不伴有心力衰竭的不同步犬模型中，斑点追踪得出的径向应变比TDI速度更准确地检测心脏不同步。
