Interobserver,Intraobserver and Intrapatient Reliability Scores of Myocardial Strain Imaging with 2-D Echocardiography in Patients Treated with Anthracyclines

Myocardial strain imaging with 2-D echocardiography is a relatively new noninvasive method to assess myocardial deformation. To determine the interobserver, intraobserver and intrapatient reliability scores, we evaluated myocardial strain measurements of 10 asymptomatic survivors of childhood cancer. Ten patients were selected randomly out of a follow-up cohort of childhood cancer survivors. All 10 patients underwent a transthoracic echocardiographic examination. Two-dimensional gray scale images were made in parasternal apical four-chamber, apical two-chamber, midcavity short-axis and basal short-axis views. Offline analysis was performed using software for echocardiographic quantification (Echopac 6.1.0, GE Medical Systems, Horten, Norway). All echocardiographic studies were analyzed offline by three observers, separately (A.M., G.W., M.P.). A custom-made software package was designed for averaging the strain curves of three consecutive cardiac cycles. Values of peak systolic strain, time-to-peak strain and time-to-end systole of the different segments of the left ventricle were used for statistical analysis. Interobserver, intraobserver and intrapatient reliability were expressed as intraclass correlation coefficients (ICCs). Interobserver ICCs of peak strain, time to peak strain and time to aortic valve closure (AVC) were generally good to very good in all views and segments, except for in the two-chamber view. Intraobserver ICCs were rated as very good for almost all segments, except for the longitudinal peak strain values of the two-chamber view. Intrapatient ICCs were generally good for the two-chamber, four-chamber and midcavity short-axis views, but fair to moderate for the segments of the basal short-axis view (SaxMV). We recommend use of the four-chamber view for longitudinal peak strain values, and the basal and midcavity short-axis views for radial and circumferential peak strain values. Furthermore, we strongly recommend using the average of three cardiac cycles for peak strain values in clinical studies. (E-mail: A.Mavinkurve@cukz.umcn.nl)     

实时心肌声学造影与二维应变成像技术评价心肌梗死后患者心肌存活性

目的 探讨实时心肌声学造影与二维应变成像技术评价心肌梗死后患者存活心肌的价值.方法 20例准备进行血运重建术心肌梗死患者,于术前1周内行实时心肌造影检查,根据心肌灌注结果进行半定量评价:3分为充盈缺损,2分为回声稀疏不均匀及心内膜下充盈缺损,1分为回声均匀性增强;MCE定义心肌存活性为心肌灌注计分≤2分,而心肌充盈缺损表示无心肌存活性.血运重建术前及术后3个月分别获取心尖位四腔、两腔及左心长轴切面二维图象,进行室壁运动评分,根据术后的室壁运动有否改善分为存活心肌组和无存活心肌组,测定术前左室各节段心肌的收缩期纵向峰值应变.结果 (1) 血运重建术前,二维超声心动图发现共有90个室壁明显发生节段性运动异常,其中有70个室壁的节段性运动异常术后得到改善.(2)血运重建术前,实时心肌声学造影评价存活心肌为65节段,无存活心肌为25节段,敏感性、特异性及准确性分别为93.8%、64%和85.5%.(3) 存活心肌组术前心肌收缩期纵向峰值应变明显高于无存活心肌组[(-7.34±5.84)% vs (-2.11±1.66)%,P＜0.001].以术前心肌收缩期纵向峰值应变≤-5.0%作为截断值判断心肌梗死时存活心肌的敏感性为72%,特异性为85%.结论 实时心肌声学造影可以准确地预测梗死心肌的存活性;同时二维应变成像技术以术前心肌收缩期纵向峰值应变≤-5.0%作为截断值也可以预测梗死心肌的存活性,其敏感性和特异性与实时心肌声学造影相当.     

Geometric Regularization for 2-D Myocardial Strain Quantification in Mice: An In-Silico Study

Myocardial strain quantification in the mouse based on 2-D speckle tracking using real-time ultrasound datasets is feasible but remains challenging. The major difficulty lies in the fact that the frame rate–to–heart rate ratio is relatively low, causing significant decorrelation between subsequent frames. In this setting, regularization is therefore particularly important to discard motion estimates that are improbable. Different regularization methods have been proposed, among which is a class of regularizers based on enforcing preset geometrical characteristics of the motion field. To date, these regularization methods have not been contrasted. The aim of this study was thus to compare the performance of different geometric regularizers in the setting of myocardial motion and strain estimation in murine echocardiography using simulated datasets. In normal models, restricting the spatial curvature of the motion fields resulted in worse radial strain estimates (mean root-mean-square [RMS] error increased from 0.06 to 0.09; p < 0.05), but better circumferential strain estimates (mean RMS error decreased from 0.035 to 0.01; p < 0.05). More accurate circumferential strain estimates were also obtained by convolving a Gaussian function with the lateral motion components (mean RMS error decreased to 0.015; p < 0.05). In infarcted models, no significant differences were found between regularized and nonregularized radial strains. However, for circumferential strain, the curvature method yielded better strain estimates in all regions (mean RMS error decreased from 0.043 to 0.015; p < 0.05), whereas the Gaussian method only improved strain assessment in the remote myocardium (mean RMS error decreased to 0.021; p < 0.05). (E-mail: florence.kremer@uz.kuleuven.ac.be)     

Left Atrial Mechanics and Integrated Calibrated Backscatter in Anthracycline-Treated Long-Term Survivors of Childhood Cancers

We tested the hypothesis that left atrial (LA) mechanics and myocardial calibrated integrated backscatter (cIB) are altered in anthracycline-treated long-term survivors of childhood cancers. Forty-nine survivors and 25 controls were studied. Survivors had significantly smaller maximal (p = 0.009) and minimal (p = 0.017) LA volumes and lower peak negative LA strains (p = 0.011). For left ventricular (LV) indices, survivors had significantly lower shortening fraction (p < 0.001), ejection fraction (p < 0.001) and mitral annular late diastolic velocity (p = 0.003). Myocardial cIB of the LA posterior wall, ventricular septum and LV posterior wall was significantly greater in survivors than controls (all p values <0.05). Peak negative LA strain was related to late diastolic mitral annular velocity (r = 0.27, p = 0.018), whereas LA cIB was related to the average of septal and LV posterior wall cIB (r = 0.54, p < 0.001). In conclusion, LA remodeling as characterized by contractile dysfunction and increased cIB suggestive of fibrosis occurs in adult survivors of childhood cancers.     

应变率显像技术评价慢性心力衰竭兔局部心肌功能的变化

目的 评价应变率显像技术(SRI)诊断慢性心力衰竭的应用价值.方法 以阿霉素耳静脉注射日本大耳兔建立心力衰竭模型(模型组,12只),对照组耳静脉注射等剂量生理盐水(对照组,6只).分别于第0、12周测定两组兔血清B型钠尿肽(BNP)水平,常规超声检测其心功能参数以及应用SRI技术检测两组兔左室侧壁和室间隔基底部心肌的收缩期和舒张早期峰值应变率(SRs和SRe)、收缩期和舒张期峰值应变(PSS和PDS)的变化.结果 两组兔于初始检测(0周)时血清BNP水平、左室舒张末期内径(LVEDD)、左室射血分数(LVEF)和短轴缩短率(FS)、心肌应变率(SRs、SRe)和心肌应变(PSS、PDS)无差异;与对照组比较,模型组兔12周时LVEDD明显增大(P<0.01),LVEF和FS均明显降低(P<0.01),SRs、SRe、PSS和PDS均明显下降.结论 心肌应变率显像技术可以评价慢性心力衰竭局部心肌的收缩和舒张特性,是有价值的诊断心力衰竭的超声技术.     

二维应变与组织多普勒评价心肌应变的对比研究

目的评价新的超声软件二维应变（2DS）在定量心肌应变与应变率中的价值。 方法采集18例正常人与15例前壁心肌梗死（心梗）患者心尖二腔长轴二维灰阶与组织多普勒（TVI）动态图，用2DS与TVI2种方法分别测量各节段心肌长轴峰值收缩速度（Vs）、峰值收缩应变（S）及应变率（Sr）并做对比；采集乳头肌水平短轴二维灰阶动态图，应用2DS测量各节段心肌径向Vs、S、Sr，对比正常与梗死节段心肌测值。 结果2DS所测正常与心梗患者的长轴Vs、S及Sr均与TVI测值无差异（P〉0．05）；2DS所测左室乳头肌水平各段心肌的径向Vs、S及Sr在正常组无差异（P〉0．05），而心梗组的梗死节段测值明显低于非梗死节段（P〈0．01），并明显低于正常组相应节段（P〈0．01）。 结论2DS可准确定量节段心肌运动速度、应变与应变率，可通过测量心肌长轴与径向的上述参数用于评价心肌功能。     

Determinants of Myocardial Strain in Experimental Chronic Myocardial Infarction

We evaluated the relationships between regional myocardial strain measured by speckle tracking echocardiography and viability, fibrosis, hypertrophy and oxygen consumption in the infarcted or remote myocardium in a pig model of chronic myocardial infarction (MI). Thirteen farm pigs with surgical occlusion of the left anterior descending coronary artery and five sham-operated pigs were studied 3 mo post-MI. Computed tomography revealed significant left ventricle remodeling. Reduced radial or circumferential strain identified areas of transmural infarction (area under the curve: 0.82 and 0.79, respectively). In the remote non-infarcted area, radial strain correlated inversely with the amount of fibrosis (r?=?–0.66, p?=?0.04) and myocyte hypertrophy (r?=?–0.68, p?=?0.03). Radial strain rate inversely correlated with myocardial resting oxygen consumption assessed with ¹¹C-labeled acetate positron emission tomography (r?=?–0.71, p?=?0.006). In conclusion, myocardial strain and strain rate reflect fibrosis, hypertrophy and oxygen consumption of the remote areas after MI.     

Left Ventricular Longitudinal Strain and Strain Rate Measured by 2-D Speckle Tracking Echocardiography in Neonates During Whole-Body Hypothermia

The purpose of the study was to assess changes in cardiac performance in newborn infants with hypoxic-ischemic encephalopathy during therapeutic hypothermia and rewarming with two-dimensional speckle tracking echocardiography. For eight asphyxiated neonates (median birth weight (range): 3038 (2725–3253) g; umbilical artery pH: 6.9 (6.8–7.18) undergoing whole-body hypothermia (33–34°C), left ventricular longitudinal strain and strain rate, as well as heart rate, cardiac output and left ventricular fractional shortening, were determined at four points in time: the start (T1) and end of hypothermia (T2), immediately after rewarming (T3) and the age of 5 to 7 d (T4). Mean (standard deviation) heart rate increased from 93 (12) beats/min at T1 to 133 (12) beats/min at T4 (p < 0.001). Cardiac output was low during hypothermia (T1: 207 [43] mL/kg/min, T2: 240 [70] mL/kg/min) and increased significantly (p < 0.001) afterward (T3: 329 [70] mL/kg/min, T4: 388 [78] mL/kg/min). Left ventricular fractional shortening remained unchanged. Left ventricular global longitudinal peak systolic strain did not differ significantly between hypothermia and rewarming, whereas the systolic strain rate increased from −1.1 (0.3) s^-1 at T1 to −1.8 (0.26) s^-1 at T4 (p = 0.001). Hypothermia affects peak systolic strain rate, heart rate and cardiac output, with complete recovery after rewarming, whereas peak systolic strain and fractional shortening remain stable.     

Assessing Common Sleep Disturbances in Survivors of Childhood Cancer

The number of children, adolescents, and young adults transitioning into primary care is steadily increasing as the overall survival rates for childhood cancer improve. Survivors of childhood cancer are at significant risk for co-morbidities associated with their primary cancer and cancer therapy impacting their health-related quality of life. Sleep disturbances are now recognized as a public health concern and are common complaints among survivors of childhood cancer. This review will describe the most common sleep disturbances reported among survivors of childhood cancer, as well as appropriate evaluations to confirm sleep diagnosis and prescribed treatments.     

超声心动图结合二维应变评价左室再同步化治疗慢性心力衰竭患者的短期疗效

目的:应用二维应变超声心动图评价慢性心力衰竭(chronic heart failure,CHF)患者在安装三腔起搏器进行左室再同步化治疗(cardiac resynchronization therapy,CRT)后的短期疗效。方法:选择行植入CRT的患者31例,分别在CRT术前、术后2周及术后3个月测量左室射血分数(left ventricular ejection fraction,LVEF)、左室舒张末内径(left ventricular end-dia-stolic diameter,LVEDD)、左室收缩末内径(left ventricular end-systolic diameter,LVESD),应用二维应变成像技术分析左室壁16个节段的径向应变(radial strain,RS)峰值、环向应变(circumferential strain,CS)峰值及纵向收缩期(longitudinal systolic strain,LS)峰值。结果:与术前相比,术后2周及术后3个月的LVEDD、LVESD和LVEF及左室壁16个节段的RS峰值、CS峰值和LS峰值均有不同程度改善。术后2周与术后3个月相比,LVEDD、LVESD、LVEF及左室壁16个节段的LS峰值差异均有统计学意义,而RS峰值与CS峰值差异均无统计学意义。术后2周及术后3个月心脏同步性均较术前有显著改善。结论:二维超声技术能定量检测CRT后心脏结构变化的数据。CRT术后可逆转心室重构,改善CHF患者的心功能。     

心肌造影超心动图与低剂量多巴酚丁胺负荷超声心动图识别心肌梗死后存活心肌的对比研究

目的：比较心肌造影超声心动图（MCE）与低剂量多巴酚丁胺负荷超声心动图（LDDSE）评价25例心肌梗死后心肌存活性。方法：MCE采用谐频频率1．8－3．6MHz的能量多普勒模式,按1：4的比例于收缩末期触发的方式提取图像。利声显浓度为300mg/ml,采用微量输液泵于患者左肘静脉内持续输注4分钟（2ml/min）,MCE心肌灌注结果进行半定量评价：0为无显影作用,0．5为部分或不均匀显影作用,1为完全及均匀显影作用;MCE定义心肌存活性为显影作用≥0．5分,无显影作用表示无心肌存活性。LDDSE输注剂量分别为5、10、20μg/kg/min,每期3min,采用16节段划分法在每个节段的心肌搏幅进行记分：正常运动＝1分,低动力＝2分,无动力＝3分,矛盾运动＝4分。LDDSE是计分减少≥1分定义为收缩功能储备。结果：（1）MCE前后及LDDSE前与5、10μg/（kg/min）,患者血压和心率改变无明显差异;（2）总共44个梗死节段中,MCE评价存活为28节段,不存活为16节段,LDDSE评价存活为23节段,不存活19节段（与MCE相比,LDDSE的敏感性与特异性为92％、84％）;（3）MCE与LDDSE评价心肌存活性的观察一致率为87％（Kappa:0.77)。结论：MCE与LDDSE均为评价心肌存活性的好方法。     

2-D Strain Assessment in the Mouse Through Spatial Compounding of Myocardial Velocity Data: In Vivo Feasibility

Ultrasound assessment of myocardial strain can provide valuable information on regional cardiac function. However, Doppler-based methods often used in practice for strain estimation suffer from angle dependency. In this study, a partial solution to that fundamental limitation is presented. We have previously reported using simulated data sets that spatial compounding of axial velocities obtained at three steering angles can theoretically outperform 2-D speckle tracking for 2-D strain estimation in the mouse heart. In this study, the feasibility of the method was analyzed in vivo using spatial compounding of Doppler velocities on six mice with myocardial infarction and five controls, and results were compared with those of tagged microscopic magnetic resonance imaging (μMRI). Circumferential estimates quantified by means of both ultrasound and μMRI could detect regional dysfunction. Between echocardiography and μMRI, a good regression coefficient was obtained for circumferential strain estimates (r = 0.69), whereas radial strain estimates correlated only moderately (r = 0.37). A second echocardiography was performed after μMRI to test the reproducibility of the compounding method. This yielded a higher correlation coefficient for the circumferential component than for the radial component (r = 0.74 circumferentially, r = 0.49 radially).     

能量多普勒组织成像和心肌超声造影定量心肌缺血的比较

目的：比较能量多普勒组织成像（ＤＰＴＩ）定量室壁异常运动区面积和超声造影（ＭＣＥ）显示的心肌灌注缺损区面积的关系。方法：对８条急性缺血和心肌梗塞犬模型行ＤＰＴＩ和ＭＣＥ研究。仪器使用ＡＴＬＨＤＩ３００超声诊断仪和３．５ＭＨｚ超声探头。测量冠脉结扎后６小时左室壁异常运动区面积和心肌灌注缺损区面积。结果：冠脉结扎后６小时,８条犬均获满意的ＤＰＴＩ显示,２４个区域心肌活动消失,呈现紫黑色,和正常心肌间（金黄色）有明显的分界。ＤＰＴＩ显示的平均左室缺血区面积为１．８１±０．１７ｃｍ２,ＭＣＥ显示的平均左室缺血区面积为１．９１±０．１８ｃｍ２,二者无显著性差异（Ｐ＞０．０５）,并高度相关（ｒ＝０．９９,Ｐ＜０．００１）。但该结果均大于病理切片上ＮＢＴ染色所显示的心肌梗塞面积（１．５３±０．１６ｃｍ２）（Ｐ均＜０．０１）。ＤＰＴＩ和ＭＣＥ测得的平均左室缺血区面积与病理实测值均高度相关（ＤＰＴＩ为ｒ＝０．９６,ＭＣＥ为ｒ＝０．９４,Ｐ＜０．０１）。结论：动物实验研究表明ＤＰＴＩ反映的室壁异常运动区面积和ＭＣＥ反映的心肌灌注缺损区面积没有差异。     

二维应变对室壁运动正常冠心病的应用研究

目的 应用二维应变超声心动图(2DSE)定量分析常规方法 显示室壁运动正常冠心病患者的左室收缩运动,探讨其临床应用意义.方法 采集经冠脉造影证实的38例冠心病和31例对照组患者的心尖长轴、四腔和二腔观的二维灰阶动态图像,应用二维应变软件测量左室壁各节段的收缩应变、应变率及整体长轴应变(GLS),心尖双平面Simpson 法测量左室射血分数(LVEF),比较两组参数值及分析LVEF与GLS的相关性.结果 组间比较,各项常规超声指标均无统计学差异(P>0.05),部分节段的应变、应变率及GLS有统计学差异(P<0.05或P<0.01),LVEF与GLS呈良好相关性P<0.05).结论 二维应变与应变率互为补充,对评价缺血心肌的敏感性高于常规超声心动图.     

应用斑点追踪技术对急性心肌缺血及再灌注心肌应变功能的研究

目的 应用斑点追踪技术(STI)检测急性心肌缺血及再灌注不同时间点心内膜下心肌和心外膜下心肌圆周应变的改变.方法 选取20只健康成年杂种犬,结扎左冠状动脉第一对角支,分别对结扎前、结扎即刻、结扎60、120 min和180 min及再灌注即刻、60 min和120min、基底水平、乳头肌水平和心尖水平心内膜下心肌和心外膜下心肌的圆周应变进行比较.结果 (1)在急性缺血过程中基底水平心肌圆周应变上升(P＜0.01).乳头肌水平和心尖水平心肌圆周应变下降(P＜0.01),心尖水平心肌甚至出现反向运动.再灌注后,基底水平圆周应变下降,无统计学意义(P＞0.05),乳头肌水平和心尖水平圆周应变上升(分别为P＜0.01,P＜0.05),但仍低于基础状态.(2)在急性缺血及再灌注过程中,心内膜下心肌对缺血更加敏感.(3)再灌注后心肌出现再灌注损伤.结论 斑点追踪技术可以客观定量局部及整体的心脏功能并判断心肌梗死的透壁程度及评价冠脉再通后的疗效.     

我国急性心肌梗死患者心率水平与病死率关系的Meta分析

【目的】采用Meta分析的方法确定我国人群心率水平对急性心肌梗死（AMI）患者病死率的影响,为AMI临床治疗的选择提供参考依据。【方法】全面收集国内发表的有关AMI患者静息心率与病死率关系的流行病学研究资料,对符合条件的所有研究结果利用RevMan软件进行固定效应模型和随机效应模型的Meta分析。计算AMI患者心率慢组（〈80次／分钟）和相对心率快组（〉80次／分钟）发生死亡的相对危险（RR）,评价心率快慢对AMI患者生存的影响,并用漏斗图分析发表性偏倚。【结果】符合纳入标准的共11篇文献,总样本量3484例。其中心率慢组2389例,死亡198例;心率快组1095例,死亡226例;合并RR=0．33,95％可信区间是（0．27～0．40）。漏斗图分析提示不存在发表性偏倚。【结论】AMI患者心率水平与病死率之间存在关联。AMI后心率增快者死亡危险增加,心率可能作为评估AMI患者预后的指标之一。