心脏超声增强造影技术和使用安全性的更新

 心脏超声增强造影检查是一项重要的超声诊断技术。在过去的十年里,临床影像科医师对超声仪器和微泡物理特性的理解以及安全性的认识有了进一步的更新。通过采用低机械指数谐波成像进行对比增强提高了造影效果,同时经过大规模的临床试验,对造影剂在特殊患者(包括肺高压患者)中运用的安全性的顾虑,有了进一步的澄清。本文综述了这些方面的知识进展,并提供操作要点优化检查。     

经静脉心肌声学造影术评价区域性心肌灌注的初步临床研究

目的 探讨经静脉心肌声学造影术（ＩＭＣＥ）的安全性,可行性及临床应用价值。方法 １４例住院病人行ＩＭＣＥ检查、心肌梗死６例,心绞痛６例,可疑冠心病２例。其中８例行冠脉造影术（ＣＡＧ）,７例行单光子发射计算机断层显像术（ＳＰＥＣＴ）检查。ＳＰＥＣＴ、ＩＭＣＥ均采用目测半定量方法（０￣３分）评价心肌灌注。冠脉根据其病变程度分为４组：正常（无狭窄）、中度狭窄（５０％￣７５％）,重度狭窄（７６％￣９９％）     

声学造影与超声运动试验的联合应用

为了解在心室声学造影对超声运动试验显示在室内膜的增强能力，将27例（年龄47±8岁）因胸闷接受超声平板运动试验的患者于运动后静脉注射声学造影剂，剂量为0．08ml／kg。在声学造影前后连续记录胸骨旁乳头肌短轴图像，分别分析声学造影前和造影后左心室5个节段内膜的可分辨性和测量左心室面积的误差．结果显示声学造影使运动后左心室内膜的可分辨性由42．7％显著提高到68％（P＜0．05），左心室面积的测量误差由5．4±1．6％缩小到1．6±0．9％，P＜0.01。研究认为声学造影能提高运动后左心室内膜的辨别能力，增加对室壁运动观察及测量的准确性。     

心腔和血管内压对声学造影显影效果的影响

为探讨心腔和血管内压对声学造影显影效果的影响，观察64名住院患者静脉注射声微显声学遗影剂0．08或0．22ml／kg的显影情况。结果：左心室显影强度显著低于右心室，左心室灰度于收缩期逐渐下降，收缩末期灰阶显著低于舒张末期，但右心室显影收缩期与舒张期显影效果无明显差别；收缩期显影效果与动脉收缩压呈负相关。上述结果表明：心脏和血管内压增高至一定程度可使造影剂微泡破坏，从而使显影强度减弱。     

心肌声学造影在冠状动脉慢血流中的临床应用研究进展

 冠状动脉慢血流 (coronary slow flow,CSF)是指在冠状动脉造影时未发现有明显冠状动脉狭窄,而在末梢血管出现造影剂充盈延迟的现象。随着影像学技术的不断发展与提高,这种现象的检出率也随之上升,逐渐成为国内外学者的研究热点。心肌声学造影(myocardial contrast echocardiography,MCE)是评估心肌微循环血流灌注的一项新型诊断技术,本文对其在CSF中的临床应用研究进展作一综述。     

静脉注射声学造影剂增强左心多普勒信号

为探讨经静脉左心声学造影（ILCE）在临床多普勒超声波检查中的应用，分别对25例轻中度二尖辩返流的患者及28例行肺静脉脉冲多普勒检查的患者静脉注射自制声微显声学造影剂0.08ml／kg。结果：造影后多普勒血流信号二尖瓣返流面积由3．5±4．6cm~2增加至8.0±7.5cm~2；ILCE前仅10名患者能记录到较完整的麻静脉多普勒频谱，ILCE后所有患者均能记录到较完整的肺静脉频谱。上述结果表明：ILCE可显著增加在心多普勒信号。     

实时超声心肌声学造影对冠心病患者心肌灌注的临床研究

目的应用实时心肌声学造影半定量评价冠心病患者心肌灌注状况和心肌微循环状况。方法 20例冠脉造影左前降支冠脉狭窄>75%以上的冠心病患者和20例健康对照组行静息状态下实时心肌声学造影检查,并进行左室显影效果评分及造影声像半定量分析,来评价冠心病患者心肌灌注状况和心肌微循环状况。结果 MCE技术不但可对左室显影效果及心肌造影进行直观评价,而且能同时显示心肌增厚率和室壁运动,可以作为评价冠心病患者心肌血流灌注及心肌微血管病变的最佳选择。结论心肌超声造影有望成为冠心病的常规检查方法。     

经胸超声心动图结合右心声学造影在判断卵圆孔未闭右向左分流中的临床价值

目的 探讨经胸超声心动图(transthoracic echocardiography,TTE)结合右心声学造影在判断卵圆孔未闭(patent foramen ovale,PFO)右向左分流中的临床应用价值.方法 收集2013年1月至2016年12月在我院心血管内科和神经内科接诊的不明原因脑卒中和偏头痛患者373例(其中脑卒中患者121例,偏头痛252例),为进一步诊断有无PFO,均接受TTE和右心声学造影检查,其中103例进行了经食道超声心动图(transesophageal echocardiography,TEE)检查.结果 ①在静息状态下,373例患者TTE结果显示22例合并有PFO;在TTE未检出PFO的351例患者中,103例患者同时接受了TEE检查,结果显示49例患者合并PFO.②右心声学造影检查结果显示:186例患者在Valsalva状态和剧烈咳嗽时存在不同程度的右向右向左分流检出率为49.87％.其中轻度右向左分流(Ⅰ级)69例;中度分流(Ⅱ级)70例;重度分流(Ⅲ级)47例.③TTE检测出22例PFO和TEE检测出49例PFO患者,右心声学造影均显示中度以上右向左分流.④59例TTE结合右心声学造影证实为中度以上右向左分流且MRI证实有脑梗塞灶的患者,均在TTE引导下成功进行了PFO介入封堵术,术后1个月复查经右心声学造影显示,55例在Valsalva和剧烈咳嗽状态下右向左分流消失,4例仍有少量右向左分流.结论 TTE结合右心声学造影不仅能清晰显示PFO右向左分流的存在,并可判断右向左分流程度,为PFO的临床治疗提供直接依据;同时还能作为PFO封堵术后临床随访的重要工具.     

Real-time three-dimensional myocardial contrast echocardiography in assessment of myocardial perfusion defects

Background Both real-time three-dimensional echocardiography (RT3DE) and myocardial contrast echocardiography (MCE) are novel imaging techniques. The purpose of this study was to confirm the feasibility and accuracy of RT3DE combined with MCE for quantitative evaluation of myocardial perfusion defects. Methods Thirteen dogs underwent ligation of the left anterior descending artery (LAD, n=6) or distal branch of the left circumflex artery (LCX, n=7) under general anaesthesia. Three to four ml of a perfluoropropane (C3F8) microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with a commercially available Philips SONOS-7500 ultrasound system. After removal of the dog hearts, Evans blue dye was injected via the left and right coronary arteries to stain the myocardium at risk. In vitro anatomic measurements of myocardial mass after removal of the animals’ hearts were used as controls. Results Left ventricular (LV) mass determined by RT3DE ranged 36.7-68.9 g ［mean, （54.6±9.6） g］ before coronary artery ligation, and correlated highly (r=0.99) with in vitro measurement of LV mass ［range, 38.9-71.1 g; mean, (55.6±9.3) g］. There was no significant difference between RT3DE and in vitro measurements of LV mass ［range, 36.7-68.9 g; mean, （51.3±12.5） g. Or range, 38.9-71.1 g; mean, （53.7±12.3） g, respectively］ and under-perfused mass ［range, 0-21.4 g; mean, （12.0±6.9） g. Or range, 0-19.8 g; mean, （10.8±6.3） g, respectively］ after the LAD ligation (P>0.05). Likewise, no significant difference was present between RT3DE and in vitro measurements of LV mass ［range, 50.1-65.4 g; mean, （57.5±5.9） g. Or range, 51.5-65.8 g; mean, （57.3±6.4） g, respectively］ and under-perfused mass ［range, 0-25.6 g; mean, （13.3±9.6） g. Or range, 0-22.7 g; mean, （12.8±8.1） g, respectively］ after the LCX ligation (P>0.05). For all the animals with coronary ligation, LV mass measured by RT3DE ranged 35.9-68.6 g ［mean, （54.8±10.0） g］ and there was no significant difference between RT3DE and in vitro measurements of LV mass and under-perfused mass (P>0.05, r=0.99). Further, the under-perfused mass derived from RT3DE ［range, 0-25.6 g; mean, （12.7±8.2） g］ correlated strongly with the in vitro measurements ［range, 0-22.7 g; mean, （11.9±7.2） g］ (r=0.96). Conclusion RT3DE with MCE is a rapid and accurate method for estimating LV myocardial mass and quantifying perfusion defects.     

利声显心肌超声造影对顿抑心肌血流灌注的研究

目的 了解用利声显进行心肌超声造影时顿抑心肌的灌注情况。方法 ９条健康杂种犬通过结扎左冠状动脉前降支（ＬＡＤ）制作顿抑心肌模型,经静脉注入利声显,用ＨＰ Ｓｏｎｏｓ５５００型彩超仪观察正常状态,ＬＡＤ结扎时以及松解后不同时间的心肌显像。结果 基础状态心肌显像良好;ＬＡＤ结扎时局部心肌显像不良;ＬＡＤ松解后２０￣３０ｍｉｎ时,顿抑心肌部分显像;６０ｍｉｎ时,较均匀显像,７只犬于９０ｍｉｎ、２只于１２     

Real-time myocardial contrast echocardiography and its applications in evaluation for coronary artery disease

It is important to assess myocardial perfusion in the diagnosis, treatment and risk stratification of patients with coronary artery disease. At present, single-photon emission computed tomography (SPECT) is used to evaluate myocardial perfusion, but it is limited by relatively low spatial resolution, the need to inject radioisotopes, and not being able to be performed at the     

Real-time myocardial contrast echocardiography and its applications in evaluation for coronary artery disease

It is important to assess myocardial perfusion in the diagnosis, treatment and risk stratification of patients with coronary artery disease. At present, single-photon emission computed tomography (SPECT) is used to evaluate myocardial perfusion, but it is limited by relatively low spatial resolution, the need to inject radioisotopes, and not being able to be performed at the patient ' s bedside. Using intracoronary injection of ultrasound contrast agent, the potential of myocardial contrast echocardiography (MCE) instead of perfusion assessment has been proved in numerous animal and human studies. Recent improvements in contrast agents have resulted in stable microbubbles that, following intravenous administration, traverse the pulmonary circulation and reach the left heart. Combined with the emergence of contrast-specific imaging modalities along with quantitative analytical method, intravenous MCE is now a feasible and promising noninvasive technique for perfusion assessment.     

Usefulness of dobutamine stress myocardial contrast echocardiography for assessing coronary artery disease

Background Quantitatively assessing myocardial perfusion and its reserve is of great importance for the diagnosis and stratification of patients with coronary artery disease (CAD), and represents an important goal of myocardial contrast echocardiography. In this study we sought to test the usefulness of low dose dobutamine stress real-time myocardial contrast echocardiography (RT-MCE) in the assessment of CAD, and to explore the relationship between perfusion reserve and contractile reserve.Methods Twenty-six patients with suspected or clinical diagnosed CAD were enrolled and underwent RT-MCE at baseline and under low dose dobutamine stress, and subsequent coronary angiography. RT-MCE images were analyzed quantitatively from microbubble replenishment curves for myocardial perfusion and its reserve. Results At baseline, significant differences in beta (0.28±0.12, 0.25±0.09, 0.22±0.06, 0.20±0.07 respectively, P＜0.01) and A×beta (1.37±0.46, 1.28±0.47, 1.13±0.37, 0.91±0.32, respectively, P＜0.01) were observed among four segment groups with graded coronary artery stenosis severity (normal; 30%-69% stenosis; 70%-90% stenosis; and beyond 90% stenosis), but not observed in parameter A. When under stress, significant differences in A (5.73±1.28, 5.63±1.01, 4.96±0.81, 4.57±0.62, respectively, P＜0.01), beta (0.67±0.17, 0.55±0.19, 0.32±0.13, 0.25±0.08, respectively, P＜0.01) and A×beta (3.81±1.20, 3.11±1.17, 1.59±0.82, 1.12±0.37, respectively, P＜0.01) were observed among the formerly mentioned groups. Graded decreases in A reserve (1.20±0.53, 1.11±0.16, 0.98±0.12, 0.99±0.13, respectively, P＜0.01), beta reserve (2.65±1.07, 2.32±0.82, 1.44±0.40, 1.29±0.34,respectively, P＜0.01) and A×beta reserve (3.05±1.63, 2.59±1.01, 1.42±0.44, 1.27±0.34, respectively, P＜0.01) could also be observed with increasing coronary stenosis severity. In five segments groups scored by WMS (1-5), concordance between contractile function and myocardial perfusion could be found both at rest (beta: 0.28±0.11, 0.22±0.08, 0.21±0.05, 0.17±0.05, 0.19±0.06, respectively, P＜0.01; A×beta: 1.29±0.48, 0.98±0.45, 0.94±0.29, 0.76±0.30, 0.92±0.32, respectively, P＜0.01) and under stress (beta: 0.59±0.20, 0.35±0.15, 0.27±0.08, 0.17±0.05, 0.20±0.05, respectively, P＜0.01; A×beta: 3.07±1.38, 1.62±0.82, 1.28±0.40, 0.78±0.24, 0.93±0.22, respectively, P＜0.01). This concordance is also valid in terms of the reserves, and the MCE parameters in segments with ameliorated contractile function are significantly higher than in those without. Conclusions Quantitative RT-MCE in conjunction with dobutamine stress shows promise in identifying and stratifying CAD and in exploring the perfusion-contractile correlation. Chin Med J 2005; 118(21):1766-1772     

手振50%葡萄糖在右心声学造影中的应用研究

目的　探讨右心声学造影新方法。方法　采用三通管和 2支注射器 ,用手来回推动 5 0 %葡萄糖溶液产生微气泡。对 5只兔、36例先天性心脏病进行经静脉右心声学造影检查。观察右心微气泡显影范围、显影密度、显影峰密度持续时间、左心有无显影。结果　 36例患者和 5只兔右心造影 ,显影范围及显影密度均达到 3级。临床病例造影峰密度持续时间 (17± 5 )s,造影前后ECG心律和心率无统计学差异 (P >0 .0 5 ) ,病人无任何不适。结论　手振 5 0 %葡萄糖微气泡右心声学造影是一种效果肯定、制做简单、方便易行、安全、易于在各级医院推广应用的实用方法     

经静脉心肌造影对犬冠状动脉阻断后存活心肌评价的实验研究

目的:探讨经静脉心肌造影(MCE)对犬冠状动脉阻断后存活心肌判定的价值。方法:应用自制声学造影剂,对12条犬于冠状动脉阻断即刻、阻断后1h、4h和再灌注后1h进行经静脉心肌造影研究。结果:当冠状动脉阻断后,所有犬阻断的冠状动脉供血区心肌出现节段性的灌注缺损。阻断即刻与1h的灌注缺损区面积无明显差异,而阻断4h后灌注缺损面积较前两者变小,在阻断早期灌注缺损区域部分变为正常或灌注减低区。灌注减低区对应的氯化三苯四氮唑染色显示为存活心肌。结论:冠状动脉阻断一定时间后MCE可以准确判定存活心肌。     

心肌造影超声心动图实验犬模型的建立与应用价值

目的:建立用于心肌造影超声心动图的实验犬模型并探讨其应用价值.方法:将12条健康杂种犬静脉麻醉、人工呼吸机通气,正中切口开胸暴露心脏,行心外膜超声检查,阻断冠状动脉前降支4 h,造成急性心肌缺血模型,4 h后再灌注1 h,于冠状动脉阻断前、阻断及再灌注后不同时间经静脉注射自制造影剂进行心肌造影超声心动图研究.结果:12条犬经静脉注射造影剂后获得满意心肌造影图像,7条犬完成了全部的实验.结论:正中切口开胸犬心肌缺血模型可以成功地进行心肌造影超声心动图研究.     

An assessment of the clinical utility of echocardiography criteria in a Tertiary Health Center

Background:

The rising prevalence of cardiovascular diseases in the population has increased the demand for cardiovascular imaging procedures (specifically echocardiography) in our center.

Aim:

To determine the percentage of appropriate indications for echocardiography.

Materials and Methods:

This was a prospective study conducted over a period of 1 year in the Department of Medicine of a Tertiary Health Care Center. The clinical diagnoses by the referring clinician and the indications (specific reasons for the study) for the echocardiography were consecutively recorded. The age and gender of the patients were also recorded. The indications were given a score of one to nine according to the revised appropriate use criteria of the American College of Cardiology Foundation and the American Society of Echocardiography (ASE). These indications were then classified into appropriate, inappropriate or uncertain based on the score. (1-3)-inappropriate use, (4-6) were derived.

Results:

There were 25 indications, 16 (64%) were appropriate, 6 (24%) were inappropriate and three (12%) were rated as uncertain.

Conclusion:

Sixty-four percent of the indications for echocardiography are appropriate for the procedure. This implies that the criteria for echocardiography are yet to be fully implemented resulting in overutilization of the procedure.     

实时心肌造影对可疑冠心病患者的研究

目的：探索实时心肌超声造影（RTMCE）在可疑冠心病中的左室心内膜边界及心肌显影效果。方法：49例可疑冠心病患者进行了超声心动图检查,并在静息状态下行心肌声学造影后进行冠状动脉造影并与冠状动脉造影对比分析。结果：（1）超声造影后左室心内膜边界显示较造影前明显清晰,显示不清的节段减少,清晰显示的节段增多,记分指数增高（P〈0．05）。（2）49例患者中冠脉造影15例异常,3例冠脉3支病变的患者显示心肌灌注明显下降,12例单支或双支病变的患者中7例表现为相应冠脉供血区心肌灌注下降,5例其相应冠脉供血区未见异常,3-4例冠脉造影正常者中有3例表现为灌注减弱。结论：心肌超声造影有望成为可疑冠心病及冠心病的常规检查方法。     

实时心肌造影诊断犬冠状动脉狭窄的实验研究

目的探讨实时心肌声学造影（RTMCE）在检测犬冠状动脉狭窄中的实用价值。方法对13只开胸犬冠状动脉左前降支（LAD）在狭窄前、轻度狭窄（血流量减少40%）、中度狭窄（血流量减少70%）、重度狭窄（血流量减少90%）时分别进行心肌声学造影,观察左室乳头肌短轴切面心肌显影情况,应用Real Time MC分析软件进行脱机分析,得出各心肌节段的平台期强度（A）、再充盈平均速度（）及A×值,再对各节段心肌灌注参数进行统计分析。结果在LAD狭窄前分别与LAD轻、中、重度狭窄状态下比较,A值均无统计学意义（〉0.05）;当LAD重度狭窄时,其值与狭窄前比较,两者间差异有统计学意义（〈0.05）,当LAD中度狭窄时,其供血区心肌血流量（A×）低于正常对照区,差异有统计学意义（〈0.05）,当LAD狭窄90%时,其供血区心肌血流量明显减少,显著低于正常对照区,两者间对比明显,A×差异有显著统计学意义（〈0.01）。结论 A×能较好地评价不同程度的冠状动脉狭窄,也是一个探查冠状动脉狭窄存在的理想指标。     

经胸超声心动图造影在评估偏头痛患者右向左分流中的应用价值

目的 应用经胸超声心动图造影(c-TTE)评估偏头痛患者右向左分流(RLS)的发生率、来源及半定量分级,初步探讨其与偏头痛的关系。方法186例偏头痛患者和120例健康志愿者均接受c-TTE检查。观察左心腔内是否出现造影微泡来判断有无RLS;根据微泡出现的时间将RLS分为来源于卵圆孔未闭(PFO)的分流(PFO-RLS)和肺动静脉畸形(PAVMs)的分流(P-RLS);再依据每帧图像的微泡数量对RLS的分流量进行半定量分级。比较两组人群RLS发生率、来源及分流量之间的差异。结果偏头痛组的RLS总发生率(56.4%,105/186)、PFO-RLS发生率(40.3%,75/186)及大量分流率(18.8%,35/186)均高于健康组(均P<0.05),PFO-RLS中量分流率虽高于健康组,但两组差异无统计学意义(P>0.05);两组间的PFO-RLS少量分流率、P-RLS发生率及各半定量分流率差异无统计学意义(均P>0.05)。结论偏头痛与PFO-RLS尤其伴大量分流者存在密切联系。以少、中量分流为主的P-RLS在偏头痛和健康人群亦不少见,其临床意义有待进一步研究。