心肌声学造影在冠心病中的应用

心肌声学造影(MCE)是指注射含有微气泡的声学造影剂后,应用二维或多普勒超声技术观察心肌灌注的诊断技术.近年来,随着MCE基础理论、超声造影剂与显像技术的迅速发展,MCE已从实验室研究走向临床应用,有望成为临床上实时、安全、准确评价心肌灌注的诊断技术.本文就MCE在冠心病中的应用研究现状做一综述.     

心肌声学造影及其临床应用

心肌声学造影及其临床应用四川省人民医院李春梅，综述尹立雪审校１９８４年Ｄｅｍａｒｉａ等首先应用心肌声学造影（ＭＣＥ）直接使心肌灌注显像。同年Ｇｏｌｄｍａｎ等首次在手术室内用ＭＣＥ检测冠脉搭桥术患者的心肌灌注。８０年代末、９０年代初ＭＣＥ逐步得以完善。...     

心肌声学造影——一种评价冠状动脉微循环的新技术

心肌声学造影——一种评价冠状动脉微循环的新技术刘伊丽随着选择性冠状动脉造影的广泛开展，人们逐渐发现完全闭塞的冠脉，其所属心肌由于得到充分的侧支循环供应而能长期存活；相反，急性心肌梗塞经溶栓或经皮球囊冠脉扩张术（ＰＴＣＡ）使相关冠状动脉完全再通后，所属...     

心肌声学造影的进展

心肌声学造影 (Myocardial ContrastEchocardiography,MCE)是通过注射声学造影剂的方法使之灌注到冠脉微血管结构中 ,从而使含血心肌的超声心动图显像增强 ,近年来 ,心肌声学造影已取得突破性进展 ,新一代声学造影剂的发现及超声显像技术的发展使经静脉注射声学造影剂导致心肌显像成为可能。心肌声学造影不仅能直接反映冠脉微循环状况、确定急性心肌梗塞的危险区、评价心肌存活性及冠脉血流储备 ,而且还可以用于标靶特定组织及局部药物或基因的转导。1　心肌声学造影剂196 8年 Gramiak和 Shah[1] 首次报道了经心腔注射生理盐水后经超声…     

心肌声学造影在冠心病中的临床应用进展

心肌声学造影是诊断微循环水平心肌灌注的新技术。近年来无创性的心肌声学造影取得了突破性进展,已从实验室走向临床应用,现将心肌声学造影在冠心病方面应用的研究进展做一综述。     

经静脉心肌声学造影的二次谐波显像评价钬激光心肌再血管化治 …

目的 利用经静脉心肌声学造影的二次谐波技术非损伤性评价钬激光心肌再血管化治疗心肌缺血的效果。     

心肌声学造影在心瓣膜置换术前的应用

目的探讨心肌声学造影(MCE)在心脏瓣膜置换术前诊断冠心病的敏感性和特异性。方法对40例心脏瓣膜患者行MCE及冠状动脉造影(CAG)检查,以CAG结果作为参考标准分组,计算MCE诊断冠心病的敏感性和特异性。结果 MCE诊断冠心病的敏感性为83.3%,特异性为80.0%,MCE与CAG在诊断冠心病方面差异无统计学意义(P>0.05)。结论 MCE作为无创、快速和廉价的检查方法,可作为中老年瓣膜病合并冠心病的术前筛查手段,可以大大减少有创的CAG的应用。     

心肌声学造影与第二谐波成象技术实验研究新进展

心肌声学造影评价心肌血流灌注和功能，方法简便易行，但尚有一定的局限性。国外新近推出的第二谐波成象可明显增强心腔及心肌血管超声造影剂的显影效果，两者联合作用，在评价冠脉解剖、生理功能及心肌灌注方面，有广阔的应用前景。     

心肌声学造影的临床应用

随着超声增强剂(UEA)的改良、超声成像技术的完善,心肌声学造影已成为临床无创、安全、有效、实时、价廉的新技术。该文主要介绍心肌声学造影在心脏病诊断治疗中的应用。     

静脉心肌声学造影在心肌梗死再灌注治疗及血管成形术中的应用

目的 :探讨静脉心肌声学造影 (MCE)评估急性心肌梗死再灌注治疗效果、冠状动脉介入治疗疗效以及预测存活心肌的价值。方法 :采用HP 5 5 0 0型超声心动仪 ,综合应用二次谐波、间歇成像和能量多普勒成像并采用高能量的超声波发射 ,对3 5例患者静脉注射利声显行MCE ,并行冠状动脉造影进行对比研究。结果 :3 5例患者完成MCE。 17例急性心肌梗死 (AMI)患者中 ,再灌注治疗患者MCE图象评分与保守治疗患者之间差异有显著性 (P <0 0 5 ) ;19例心肌梗死患者行介入治疗 ,共 63个血管重建术相关的心肌节段 ,在心肌梗死急性期 ,介入治疗前MCE显示心肌有灌注 ( 1分或 0 5分 )的心肌节段存活性及术后灌注改善的可能性显著高于MCE无灌注 ( 0分 )的心肌节段 (P <0 0 5 ) ,在心肌梗死陈旧期 ,介入治疗前MCE显示心肌灌注良好 ( 1分 )的心肌节段的存活性及术后灌注改善的可能性显著高于MCE灌注不佳 ( 0分或 0 5分 )的心肌节段 (P <0 0 5 )。结论 :结合多种成像技术 ,利声显可行静脉MCE。MCE可以评估AMI再灌注治疗的疗效 ,评估介入治疗的疗效并判断心肌存活性。     

Myocardial Contrast Echocardiography: Clinical Benefit and Practical Issues

Real-time bedside evaluation of myocardial perfusion after intravenous application of micro-bubbles is the ultimate goal for contrast echocardiography. Over the past decade rapid evolution has occurred in the development of contrast agents, ultrasound equipment tailored to their detection, and image interpretation. This article offers a review of the basic concepts of the technique's background, contrast agent design, and imaging technology. The major clinical indications of myocardial contrast echocardiography are evaluation of acute ischemic syndromes, diagnosis of viable myocardium following AMI, and the detection of CAD using stress contrast perfusion imaging. Furthermore, the article addresses the most significant practical problems and suggested solutions to master those problems. As major new achievements are realistic expectations for the first decade of the twenty-first century, we conclude that the coupling of a new generation of contrast agents with innovative echocardiographic instrumentation will ultimately enable the full potential of myocardial contrast echocardiography to be realized which may revolutionize modern echocardiography.     

Three-Dimensional Myocardial Perfusion Maps by Contrast Echocardiography

We evaluated the clinical applicability of a system for three-dimensional (3-D) display of a perfusion map following myocardial contrast echocardiography (MCE). The system was used in 12 patients (9 males and 3 females, mean age 52 ± 10 years) undergoing interventional treatment of chronic total coronary occlusion. In each patient three standard apical views were acquired at baseline with sonicated Iopamidol^R injections into the left coronary artery (LCA) and into the right coronary artery (RCA). Following successful recanalization of the occluded artery MCE was repeated. The patients tolerated the procedure well. Acquisition of three standard apical views provided sufficient information for the reconstruction of 3-D perfusion maps containing the 16 standard left ventricular (LV) segments. Side-by-side display of the perfusion maps obtained following LCA and RCA echocontrast injections allowed us to classify the myocardial segments (192) into three groups: (1) those supplied by one major artery (124); (2) those supplied by collaterals from contralateral or both major arteries (58); and (3) segments supplied by none of the major arteries (10). Decreased opacification was observed in 50 segments of group 2. Following successful intervention we were able to visualize the redistribution of blood flow delivered to the LV myocardium by each major coronary artery in 3-D format. We conclude that this 3-D approach, which can easily be performed with currently available ultrasound equipment, allows an estimate of the contribution of each major coronary artery to LV perfusion before and after coronary angioplasty.     

负荷超声心动图在缺血性心脏病中的临床应用进展

近年来,随着缺血性心脏病发病率的逐年升高,无创评估影像技术越来越受到人们关注.负荷超声心动图作为一项较成熟的技术,目前已用于缺血性心脏病的诊断、存活心肌的评价、危险分层和预后的评估.心肌声学造影、斑点追踪成像技术和三维超声心动图等超声新技术的发展,使负荷超声心动图的诊断准确性和特异性均有提升,相信未来会更广泛地应用于临...     

超声二次谐波心肌声学造影评价心肌的血流灌注

目的探讨心肌声学造影对冠状动脉(冠脉)病变的诊断价值。 方法静脉注射声学造影剂利声显(levovist),通过超声二次谐波技术获取心肌灌注图像,对比冠脉造影显示的冠脉支配区域的心肌灌注与超声心肌声学造影获取的心肌灌注类型的关系。按心肌灌注积分指数将异常冠脉分为3组,心肌灌注积分指数1分(A组,27支),2分≥心肌灌注积分指数＞1分(B组,24支),＞2分(C组,33支)。 结果心肌灌注积分指数与冠脉狭窄度呈中度正相关(r＝0.75,P＜0.001),3组病人的冠脉狭窄程度、心肌灌注积分指数明显差异(P＜0.001)。冠脉狭窄度＜75%者,病人室壁灌注多为正常,随着冠脉狭窄程度加重,室壁灌注出现异常。 结论静脉心肌声学造影是反映心肌灌注的有效方法,能够反应冠脉血流的改变及微循环结构的完整性变化,从而弥补了冠脉造影仅能显示心外膜下的冠脉而无法观察毛细血管水平心肌灌注的缺限。     

超声微泡造影观测钬激光心肌激光再血管化的实验研究

目的：应用经静脉注射造影剂心肌超声微泡造影探讨激光心肌再血管化的机制及对心肌缺血的治疗效果。方法：部分钳闭犬的冠状动脉前降支形成急性心肌缺血模型，用钬激光在缺血区进行心肌激光再血管化，并在缺血前、缺血后及激光打孔后取左室短轴切面进行超声微泡造影。结果：缺血后心肌超声微泡声学密度较缺血前明显降低（Ｐ＜０．００１），心肌激光再血管化后，缺血区超声微泡声学密度较缺血时明显升高（Ｐ＜０．００１），接近正常心肌超声微泡声学密度（Ｐ＞０．０５），激光再血管化区心肌超声微泡较正常心肌提前显像。结论：心肌激光再血管化可即刻明显缓解心肌缺血，使缺血区血流灌注明显改善。经静脉注射造影剂进行心肌超声微泡造影可作为观测和评价心肌激光再血管化的可靠手段，钬激光心肌再血管化的中远期效果尚待观察。     

Bulls-Eye Display and Quantitation of Myocardial Perfusion Defects Using Three-Dimensional Contrast Echocardiography

Three-dimensional (3-D) myocardial contrast echocardiography (MCE) is able to derive parallel cutting planes of the left ventricle (LV). However, assessment of the site and extent of myocardial perfusion abnormalities has to rely on the reader's 3-D mental reconstruction from the tomograms, and a manual approach has to be employed for quantitative analysis. The objective of this study was to explore the display and quantitative capability of a bulls-eye format from contrast 3-D MCE in the assessment of perfusion abnormalities derived from a canine model of acute myocardial infarction (MI). Three-dimensional MCE data were acquired sequentially in a rotational scanning format during triggered harmonic imaging with an intravenous contrast agent. Reconstructed short-axis views of the LV were aligned in a bulls-eye format with the apex as the inner most ring. The total LV was divided into 120 sectors. The number of sectors with lack of contrast enhancement was used to derive the percent of the LV (%LV) with perfusion defect and was compared with the extent of MI calculated from postmortem triphenyl tetrazolium chloride (TTC) staining. The perfusion defect regions shown on bulls-eye images corresponded correctly with the territories of the occluded coronary arteries. Three-dimensional MCE perfusion defect mass (19.2 +/- 6.0 %LV) correlated well with anatomic MI mass (19.3 +/- 5.6 %LV; r = 0.92, SEE = 2.3%, mean differential = 0.1 +/- 2.4%). We conclude that bulls-eye display of contrast 3-D MCE demonstrates the site and extent of perfusion abnormalities in an easily appreciable manner. It also allows fast and accurate assessment of endangered myocardium.     

Evaluation of Postinfarction Viable Myocardium at Jeopardy by Dobutamine Echocardiography and Myocardial Contrast Echocardiography

Both myocardial contrast echocardiography (MCE), obtained by intracoronary injection of sonicated Ioxaglate, and dobutamine echocardiography (DE) were performed before and after percutaneous transluminal coronary angioplasty (PTCA) in a patient with recent myocardial infarction, an occluded infarct related artery (IRA) and collateral flow. An opposite response to low and high dose dobutamine (increase and decrease in regional contractility, respectively) suggested the presence of viable myocardium at jeopardy in the infarcted area. This myocardial area was exclusively perfused by collateral circulation (demonstrated by MCE) supplied by an angiographically normal left coronary artery. After PTCA, right coronary artery flow was re-established and angiographically demonstrated collateral flow disappeared. MCE showed a normal right coronary artery perfusion bed and relevant overlap areas after left coronary MCE injection. Dobutamine echocardiography performed after PTCA demonstrated persistence of viability, but disappearence of myocardial ischemia.     

Harmonic Power Doppler Contrast Echocardiography: Preliminary Clinical Results

Background: In fundamental and second harmonic echocardiography new contrast media opacify the cavities and reduce the difference in the gray level between the cavity and the myocardium thus obscuring the borders of the myocardium. Objectives: The aim of the study was to examine the potential usefulness of second harmonic power Doppler imaging (HPD) in providing adequate delineation of the myocardium from the left ventricular (LV) and right ventricular (RV) cavities during intravenous contrast echocardiography. Using HPD, microbubbles in a cavity or a tissue are imaged as colored pixels superimposed on a conventional B-scan image. Methods: In a pilot study, three healthy volunteers and two patients with ischemic heart disease were investigated using an ATL-HDI 3000 echo system. Four chamber views were obtained using fundamental B-scan, harmonic B-scan two-dimensional echocardiography (H2D) and HPD following intravenous injections of 3 g Levovist*. Results: Using intermittent scanning/recording, H2D and HPD provided intensive and homogenous contrast effects in the RV and LV cavities. Good delineation of the myocardium was found in all subjects using HPD, whereas in two of three volunteers and in one of two patients ventricular septal and apical endocardial borders were obscured during H2D. No obvious change in myocardial backscatter was visually found with H2D. However, in all three healthy volunteers and in one of two patients, HPD recordings demonstrated patchy and reticular patterns in the myocardium, which were different from the homogenous signals in the LV cavity. These are consistent with imaging of intramyo-cardial coronary vessels. Conclusions: HPD with intravenous Levovist is feasible. This technique demonstrated good delineation of ventricular cavities from the myocardium as well as presence of visible contrast in the myocardium. This pilot study justifies further clinical trials to evaluate the clinical benefit of this approach.