左室压力-应变环结合四维应变技术评价冠心病患者 左心功能的初步研究

【摘要】 目的 应用左室压力-应变环（LV PSL）结合四维应变技术（4D-SI）评估冠心病患者左心功能改变及心肌做功变化,探讨各参数诊断冠心病的价值。 方法 疑诊冠心病患者57例,根据冠脉造影结果分为两组：冠心病组（至少一支冠脉狭窄≥50%）27例;对照组（冠脉无狭窄或狭窄＜50%）30例。分别采集受试者心尖四腔、两腔、左室长轴切面实时三维图像,应用Echo PAC工作站应用心肌做功分析模式,得出左室-压力应变环,获取长轴整体做功指数（GWI）、整体有效功（GCW）、整体无效功（GWW）、整体做功效率（GME）;应用左室四维自动分析功能(4D Auto LVQ),获取左心室整体的长轴应变(4D-GLPS)、环向应变(4D-GCPS)、面积应变(4D-GAPS)及径向应变(4D-GRPS)。结果 与对照组比较,冠心病组GLS、GWI、GCW、GME、4D-GLPS、4D-GCPS、4D-GAPS、4D-GRPS减低,GWW升高,差异均有统计学意义（P＜0.05）;各参数ROC曲线显示4D-GLPS、4D-GAPS、GWW诊断冠心病患者左心室心肌功能受损的曲线下面积相对较高,分别为0.881、0.844、0.756。截断值分别为-13.5%、-22.5%、72%,灵敏度分别为81%、81%、64%,特异度分别为83%、73%、96%;两种技术结合的ROC曲线显示4D-SI技术各参数联合左室压力-应变环技术的GWW值得出的AUC相对较大（0.943）,灵敏度、特异度和约登指数分别为89%、90%、0.79。结论4D-GLPS、4D-GAPS和GWW是评价冠心病患者左心功能改变更为可靠的指标。将LV PSL与4D-SI两种技术结合,可从多个角度更好的评价冠心病患者左心功能的改变情况,为临床医生在评估缺血患者时提供更多的信息。     

二维应变超声心动图评价冠心病患者左室心肌功能的应用研究

目的应用超声二维应变技术定量分析室壁运动正常的冠心病患者心肌应变,并探讨其诊断室壁运动的临床应用价值。方法 35例冠状动脉造影证实的冠心病患者与对照组30例正常人进行对比研究,分别记录左室短轴（二尖瓣、乳头肌、心尖部）切面和心尖位四腔切面、二腔切面,左室长轴高帧频图像,应用二维应变软件测量左室壁各节段的峰值收缩应变,比较冠心病组与正常对照组各参数值。结果正常对照组各室壁自基底段向心尖段纵向应变逐渐增加,各壁间差异无统计学意义。冠心病组各节段均一分布的规律消失,各段室壁应变值低于正常对照组,部分节段的应变值有统计学意义。结论超声二维应变技术可准确评价室壁运动异常,为临床评价冠心病患者左心收缩功能提供无创性新方法。     

实时心肌声学造影对冠心病患者心肌灌注的定量评价

目的探讨实时心肌声学造影(RTMCE)定量分析冠心病患者心肌血流量的临床应用价值。方法对20例冠脉造影左前降支冠脉狭窄>75%以上的冠心病患者(观察组)和20例健康体检者(对照组)行静息状态下RTMCE检查,同时应用超声心动图检测造影剂峰值密度(A)、心肌血流速率(β)、心肌血流量(MBF,MBF=A×β)、左室舒张末期内径(LVEDD)、左室收缩末期内径(LVESD)、射血分数(EF)、舒张早期峰值血流速度(Emax)、舒张晚期峰值血流速度(Amax)。比较两组相应节段的心肌灌注情况和心脏功能。结果观察组β及MFB均显著低于对照组(P均<0.01),LVEDD、LVSED、EF、Emax、Amax、Emax/Amax、Dt等两组比较无明显差异。结论冠心病患者心肌血流速度减慢,存在心肌微循环损伤;RIMCE可定量评价缺血心肌的血流灌注状况。     

实时心肌超声造影及其在冠心病的应用价值

实时心肌超声造影利用高能量超声破坏微泡后再充盈速率和平台信号强度反映心肌微循环.该技术操作方便,可同时获得灌注和功能信息,对于检测冠心病、判断冠状动脉狭窄程度、评价心肌存活性、确定危险或梗死区面积、评价梗死后心肌再灌注以及无复流或低灌注现象等提供了重要手段.     

实时心肌超声造影及其在冠心病的应用价值

实时心肌超声造影利用高能量超声破坏微泡后再充盈速率和平台信号强度反映心肌微循环。该技术操作方便,可同时获得灌注和功能信息,对于检测冠心病、判断冠状动脉狭窄程度、评价心肌存活性、确定危险或梗死区面积、评价梗死后心肌再灌注以及无复流或低灌注现象等提供了重要手段。     

四维应变技术评价冠心病患者PCI术前后左室舒张功能的研究

目的 应用四维应变成像 (4D-SI) 技术评价冠心病患者PCI术前后左室舒张功能。方法 根据疑似冠心病患者行冠脉造影术及左心导管检查结果,选取44例患者分为病例组：冠心病并左室舒张功能不全患者(需行PCI术)26例;对照组：冠心病并左室舒张功能正常18例。分别采集对照组及病例组PCI术前、术后3个月的常规超声心动图检测指标,测量左室舒张末期容积 (LVEDV) 、左室收缩末期容积 (LVESV) 、左室射血分数 (LVEF) ;运用 4D-SI 技术测得收缩末期纵向应变(GLS)、径向应变(GRS)、面积应变(GAS)、圆周应变(GCS)、纵向应变显像舒张指数(LSI-DI)、面积SI-DI (ASI-DI)、 径向SI-DI(RSI-DI)、圆周SI-DI(CSI-DI)。 结果 1.病例组GLS、GCS、GAS、GRS、LSI-DI、CSI-DI、ASI-DI、RSI-DI均小于对照组(P＜0.05);病例组术后3月各参数均大于病例组术前(P＜0.05);2. ROC 曲线分析结果显示LSI-DI的曲线下面积(AUC)0.921,截值为50.107%,灵敏度和特异性分别为89.2%、81.3%;ASI-DI的AUC 0.887,截值为49.233%,灵敏度和特异性分别为86.4%、79.1%。 结论 PCI术可有效改善冠心病患者左心室舒张功能,4D-SI的相关指标在一定程度上可评价冠心病患者左室舒张功能受损及PCI术后左室舒张功能的改善情况。     

实时心肌超声造影与磁共振心肌灌注延迟增强检测存活心肌的比较

目的评价实时心肌超声造影(RT-MCE)与磁共振心肌灌注延迟增强(DE-MRI)检测存活心肌的临床价值。方法入选2012年7月至2013年12月徐州矿务集团总医院(徐州医学院第二附属医院)心内科收治入院的冠状动脉粥样硬化性心脏病(冠心病)患者27例,男性16例,女性11例,平均年龄62.5岁。所有患者行RT-MCE、DE-MRI、冠状动脉造影(CAG)及冠状动脉介入治疗(PCI)。对患者的RT-MCE图像分析采用目测半定量法,判定存活心肌;对心肌灌注延迟增强情况进行分级,根据分级结果对心肌存活情况进行判定。术后1、3、6月时复查心脏超声,以冠状动脉血运重建后室壁节段收缩功能改善为判断存活心肌的金标准。结果 RT-MCE目测半定量法检测存活心肌的灵敏性、特异性及准确度分别是70.9%、85.7%、76.3%;DE-MRI法检测存活心肌的灵敏性、特异性及准确度分别是72.7%、76.2%、74.0%,RT-MCE目测半定量法检测存活心肌较DE-MRI法具有较高的特异度(76.2%vs.85.7%,P0.05)。两种检测方法的相关性良好。结论 RT-MCE目测半定量法与DE-MRI法检测存活心肌具有较高的临床价值,RT-MCE目测半定量法具有更高的特异性。     

心肌造影多巴酚丁胺负荷超声心动图定量评价冠心病患者心肌灌注的临床研究

目的 探讨心肌造影超声心动图(MCE)联合多巴酚丁胺负荷超声心动图(DSE)定量评价动脉粥样硬化性心脏病即冠心病患者心肌血流灌注的临床价值,及不同程度狭窄冠状动脉供血心肌的微循环变化特点.方法 32例临床确诊的冠心病患者进行MCE联合DSE即心肌造影多巴酚丁负荷超声心动图(MCE-DSE)检查,根据冠状动脉造影结果将不...     

心肌声学造影与心肌造影负荷超声心动图在冠心病的研究进展

心肌声学造影（myocardial contrast echocardiography,MCE）是诊断微循环水平心肌灌注的新技术,利用声学微气泡作为造影剂经冠状动脉或周围静脉注入,应用超声技术接收声学微气泡的背向散     

磁共振组织追踪技术评价冠心病患者心肌应变的改变

目的:探讨心血管磁共振组织追踪(CMR-TT)技术的应变量化,分析能否识别冠心病患者缺血和梗死的心肌节段。方法:应用CVI软件,分析在我院接受负荷灌注CMR检查的冠心病患者109例的左心室节段周向和纵向心肌应变,同时分析在我院接受常规CMR检查的健康志愿者50例。进行应变参数的组间比较、组内相关系数(ICC)分析。结果:冠心病组非缺血节段周向和纵向应变(取绝对值)(19. 81±4. 77)%、(17. 62±5. 24)%均低于健康人组(20. 93±4. 23)%、(18. 94±4. 89)%,P均0. 01。冠心病组非缺血节段的周向和纵向应变值(取绝对值)(19. 81±4. 77)%、(17. 62±5. 24)%,P0. 05缺血节段(18. 72±4. 95)%、(16. 05±4. 95)%梗死节段(15. 30±4. 80)%、(14. 78±5. 21)%,P均0. 05。节段周向应变(ICC=0. 873)和纵向应变(ICC=0. 799)均有良好的观察者内一致性;节段周向应变(ICC=0. 818)和纵向应变(ICC=0. 725)也有较好的观察者间可重复性。结论:CMR-TT技术具有较好的临床可行性及可重复性,可在无需使用对比剂的情况下从功能学方面评估心肌运动。     

Quantitative intravenous myocardial contrast echocardiography predicts recovery of left ventricular function after revascularization in chronic coronary artery disease

BACKGROUND: Quantitative intravenous myocardial contrast echocardiography (MCE) has been shown to measure regional myocardial blood flow velocity noninvasively. PURPOSE: To determine whether quantitative intravenous MCE could be used clinically to predict functional recovery after revascularization in patients with chronic coronary artery disease. METHODS: Twenty-eight patients with chronic stable coronary artery disease and resting regional left ventricular dysfunction were included in this study. The study permits myocardial perfusion analysis by intravenous MCE before revascularization with continuous infusion of Levovist and intermittent ultrasonic exposure. Wall motion assessment by echocardiography at rest was repeated after long-term follow-up period (7 +/- 2 months). In dysfunctional segments, we analyzed myocardial perfusion quantitatively by fitting to an exponential function, Y = A(1 - e-betat) to obtain the rate of rise (beta) of background-subtracted intensity, which represented myocardial blood flow velocity. RESULTS: Of the 101 revascularized dysfunctional segments, MCE was adequately visualized in 91 (90%) segments, and wall motion was recovered in 45 (49%) segments. The value of beta in the recovery segments was significantly higher than that in nonrecovery segments (0.80 +/- 0.50 vs 0.39 +/- 0.24, P < 0.001). The value of beta > 0.5 predicted recovery of segmental function with a sensitivity of 71%, specificity of 78%. CONCLUSION: Quantitative intravenous MCE can predict functional recovery after revascularization in patients with chronic coronary artery disease.     

Physiologic assessment of left anterior descending coronary artery stenosis by quantitative intravenous myocardial contrast echocardiography in humans: comparison with exercise single-photon emission computed tomography

OBJECTIVE: To clarify the potential of quantitative intravenous myocardial contrast echocardiography (MCE) for physiologic assessment of the left anterior descending artery (LAD) stenosis. METHODS: We studied 38 patients with suspected coronary artery disease. MCE was performed by continuous infusion of Levovist and intermittent ultrasonic exposure. Images were obtained from the apical four-chamber view at rest and after dipyridamole infusion. The background-subtracted intensity versus pulsing interval plots were fitted to an exponential function,Y=A(1 e-ss), to obtain the plateau level (A) and rate of rise (ss) of background-subtracted intensity both at rest and after dipyridamole infusion. We compared the results with those of exercise thallium-201 single-photon emission computed tomography (SPECT). RESULTS: Of the 38 patients, 18 patients exhibited redistribution in the LAD territories with SPECT (group A), although 20 did not (group B). The ss reserve (DIP/rest) in group A was significantly lower than those in group B (0.8 +/- 0.5 versus 2.0 +/- 1.1, P < 0.001), while the A reserve did not differ between the two groups (1.2 +/- 0.6 versus 1.0 +/- 0.5, P = NS). The ss reserve <1.1, which was the optimal cutoff value, provided sensitivity of 79% and specificity of 84% for the presence of redistribution in SPECT. CONCLUSIONS: Quantitative intravenous MCE allows us to estimate physiologic severity of the LAD stenosis in the clinical setting.     

Real-time perfusion imaging: a new echocardiographic technique for simultaneous evaluation of myocardial perfusion and contraction

Myocardial contrast echocardiography (MCE) with high acoustic energy and triggered harmonic imaging is the best established ultrasound technique to date for the assessment of myocardial perfusion. With this technique, however, the ultimate goal of MCE (noninvasive real-time simultaneous assessment of myocardial perfusion and function after an intravenous injection of microbubbles) is not met. Recently, technologic advances have enabled myocardial opacification to be visualized during low-energy real-time imaging. During real-time perfusion imaging, wall motion and myocardial perfusion may be assessed simultaneously, obviating the need of the presently time-consuming combination of different imaging modalities. When high-energy ultrasound bursts are periodically transmitted to produce bubble destruction during low-power imaging, the consecutive frames after destruction delineate the restoration of contrast intensity. Microbubble replenishment rate and peak intensity may be determined subsequently, and provide reliable quantitative parameters of regional microcirculatory flow. This review will introduce the modalities used for real-time perfusion imaging with focus on power pulse inversion imaging and quantitative analysis. Furthermore, we will describe the clinical role the technique may have in the identification of coronary artery disease, quantification of coronary stenosis severity, assessment of myocardial viability, determination of infarction size, and evaluation of reflow and no- or low-reflow after acute myocardial infarction.     

Evaluation of left atrial function in patients with coronary artery disease by two-dimensional strain and strain rate imaging

Background: Left ventricular (LV) dysfunction in patients with coronary artery disease is shown by strain and strain rate imaging. However, left atrium (LA) function in patients with coronary artery disease (CAD) has not been assessed by this method. Methods and Results: In 34 CAD patients, including 17 patients with enlarged LA (LA diameter ≤ 4.0 cm) and 17 with normal‐size LA (LA diameter ≤ 4.0 cm), two‐dimensional strain echocardiographic imaging (2DSE) was performed. Twenty healthy subjects as a control group were included. Both conventional parameters and strain parameters, such as LA peak systolic strain (LAs S/SR), preatrial contraction strain (LAa S), peak systolic (LAs SR), early diastolic strain rate (LAe SR) and late diastolic strain rate (LAa SR), were measured. Conventional parameters were abnormal in CAD patients with enlarged LA (ELA), but there were no significant differences between CAD with normal‐size left atrium (NLA) and control groups. LAs S/SR and LAe SR were lower in patients than in normal controls, and were even lower in CAD‐ELA group (P < 0.05). LAa S/SR were lower in CAD patients with ELA (P < 0.05), but without a significant difference between CAD‐NLA and control groups. A significant correlation was observed between LAs S/SR and LA emptying fraction (r = 0.85, P < 0.05; r = 0.72, P < 0.05, respectively). LAa S/SR related well to LA ejection fraction (r = 0.68, P < 0.05; r = 0.61, P < 0.05, respectively). LAs SR was most accurate in identifying both CAD patients with NLA from controls and CAD patients from controls (area under the curve: 0.91; 0.95, respectively). Conclusions: LA diastolic dysfunction occurs prior to LA systolic dysfunction in CAD patients, and LAs SR is the most accurate index in identifying patients with CAD. (Echocardiography 2011;28:1095‐1103)     

Real time myocardial contrast echocardiography during supine bicycle stress and continuous infusion of contrast agent. Cutoff values for myocardial contrast replenishment discriminating abnormal myocardial perfusion

BACKGROUND: Myocardial contrast echocardiography (MCE) is a new imaging modality for diagnosing coronary artery disease (CAD). OBJECTIVE: The aim of our study was to evaluate feasibility of qualitative myocardial contrast replenishment (RP) assessment during supine bicycle stress MCE and find out cutoff values for such analysis, which could allow accurate detection of CAD. METHODS: Forty-four consecutive patients, scheduled for coronary angiography (CA) underwent supine bicycle stress two-dimensional echocardiography (2DE). During the same session, MCE was performed at peak stress and post stress. Ultrasound contrast agent (SonoVue) was administered in continuous mode using an infusion pump (BR-INF 100, Bracco Research). Seventeen-segment model of left ventricle was used in analysis. MCE was assessed off-line in terms of myocardial contrast opacification and RP. RP was evaluated on the basis of the number of cardiac cycles required to refill the segment with contrast after its prior destruction with high-power frames. Determination of cutoff values for RP assessment was performed by means of reference intervals and receiver operating characteristic analysis. Quantitative CA was carried out using CAAS system. RESULTS: MCE could be assessed in 42 patients. CA revealed CAD in 25 patients. Calculated cutoff values for RP-analysis (peak-stress RP >3 cardiac cycles and difference between peak stress and post stress RP >0 cardiac cycles) provided sensitive (88%) and accurate (88%) detection of CAD. Sensitivity and accuracy of 2DE were 76% and 79%, respectively. CONCLUSIONS: Qualitative RP-analysis based on the number of cardiac cycles required to refill myocardium with contrast is feasible during supine bicycle stress MCE and enables accurate detection of CAD.     

Detection of resting myocardial perfusion defects by SonoVue myocardial contrast echocardiography

BACKGROUND: SonoVue is a new microbubble contrast agent containing sulfur hexafluoride. We assessed the efficacy of SonoVue myocardial contrast echocardiography (MCE) to detect resting perfusion abnormalities. Methods: Nineteen adult patients with a wall motion abnormality in a screening echocardiogram were studied. Each patient received up to four bolus injections of 2.0 mL SonoVue (Bracco Diagnostics, Inc.) during echocardiographic examination using either B-mode(n = 12)or power Doppler(n = 7)imaging. Each patient also had SPECT nuclear perfusion imaging performed. Segmental assessment of myocardial perfusion from SonoVue MCE images were compared with corresponding SPECT nuclear images. RESULTS: Using B-mode imaging, the mean number of views obtained with a single SonoVue injection ranged from 1.4 to 1.9, with 2 or 3 injections required for a complete examination. Ninety-four percent of segments were scored as diagnostic. Agreement between B-mode and SPECT images was 72% for segments with a perfusion defect, 86% for normal perfusion, and 80% for segments with either perfusion defect or normal perfusion (all views combined). Using power Doppler imaging, the mean number of views obtained with a single SonoVue injection ranged from 1.0 to 1.3, with 2 to 4 injections required for a complete examination. Sixty-eight percent of segments were scored as diagnostic. Agreement between power Doppler and SPECT images was 67% for perfusion defects, 53% for segments with normal perfusion, and 59% for segments with either perfusion defect or normal perfusion (all views combined). CONCLUSIONS: SonoVue MCE has the potential to assess myocardial perfusion at rest. B-mode imaging was more accurate than power Doppler imaging when compared with SPECT nuclear imaging.     

Assessment of myocardial perfusion by power contrast imaging using a new echo contrast agent

In a patient with previously documented myocardial infarction, we assessed myocardial perfusion by using power contrast imaging and a newer intravenous echo contrast agent. The images were captured and stored digitally, and various image processing algorithms were used to assess myocardial perfusion. An apical perfusion defect was clearly visualized, and it correlated with radionuclide findings.     

Transmural myocardial strain gradient: a new and robust quantitative index of left ventricular wall motion based on myocardial strain imaging

Background: Peak strain has been promising as an index of wall motion but it is sometimes susceptible to the image quality. Objective: We investigated the feasibility of a novel index, transmural myocardial strain gradient (TMSG), derived from myocardial strain M‐mode imaging (TDI‐Q, Toshiba) for quantifying regional systolic wall motion. Method: We measured transmural myocardial strain distribution at the left ventricular lateral, posterior, inferior, septal, anteroseptal and anterior walls in the basal and midventricular short‐axis images using TDI‐Q. Twenty normals (35 ± 3 years) and 35 consecutive patients (63 ± 9 years) with coronary artery disease (CAD, 19 patients with old myocardial infarction, 4 patients with acute myocardial infarction, 12 patients with angina pectoris) were studied. Peak strain, endocardial‐ and epicardial‐half strain and TMSG ((peak strain, ? epicardial strain)/distance between peak and epicardial points) were obtained. Coefficient of variation (CV) of each index was calculated. Results: In control subjects, the best reproducibility of the variables was obtained for TMSG with the smallest CV (11.6%) (27.8%, 28.1%, and 35.5%, respectively for CV of peak strain, endocardial‐ and epicardial‐half strain). All segments in control subjects and normal segments in CAD patients showed no significant difference in TMSG (15.1 ± 1.8 vs. 15.1 ± 1.6%/mm, P = ns). TMSG was the lowest for akinetic segments and highest for the normal segments (P < 0.001). Conclusion: TMSG was more robust than simple strain values to quantitatively assess wall motion. This could successfully identify subtle regional differences in wall function. (Echocardiography 2011;28:181‐187)