超声心动图在诊断心肌淀粉样变中的价值

目的探讨超声心动图在诊断心肌淀粉样变中价值,提高其超声诊断的准确率。方法回顾性观察分析4例原发心肌淀粉样变患者的超声声像图表现。结果心肌淀粉样变患者室间隔及左室游离壁不同程度增厚,内可见散在“闪烁样”的高回声,呈“毛玻璃样”改变。尚可出现房间隔及房室瓣不同程度增厚、双房增大、左室收缩功能减低、舒张功能受损、心包积液等声像图表现。结论当系统性淀粉样变性累及心脏时,超声心动图在其诊断及鉴别诊断方面均具有重要的临床价值。     

成人心肌致密化不全的超声心动图分析

目的探讨成人心肌致密化不全(NVM)的超声心动图特征。方法对8例NVM行经胸超声心动图检查,重点观察左心室壁的结构和运动,心功能的改变以及各瓣膜的返流情况。结果7例为左室型,1例为右室型。8例NVM均有粗大的肌小梁和小梁间深陷的陷窝,彩色多普勒可探及间隙内有血流与心腔相通,均有室壁运动的减弱,心功能的减低,瓣膜的返流,其程度与非致密化心肌的累及范围有一定的关系。结论NVM具有特征性超声心动图改变,仔细分析可以对其进行准确诊断。     

心肌致密化不全12例超声心动图特征及临床意义

0引言 心肌致密化不全（NVM）是一种罕见的因正常心内膜胚胎发育停止导致的先天性心肌病,临床上常误诊为扩张型心肌病（DCM）,我们通过比较二者的超声心动图表现,探讨NVM的超声心动图特征及诊断价值．     

二尖瓣部分腱索断裂的超声心动图诊断分析

目的探讨二尖瓣部分腱索断裂的超声心动图表现。方法对20例典型的二尖瓣部分腱索断裂患者的超声图像进行归纳分析,总结其特点。结果二尖瓣腱索的梿枷样运动是诊断二尖瓣部分腱索断裂的超声特征性改变。结论对怀疑有二尖瓣部分腱索断裂的患者,超声心动图可作为诊断此病的首选方法,但需要仔细观察,以防错漏诊。     

心肌致密化不全的超声心动图诊断分析

目的 分析成人心肌致密化不全(NVM)的超声心动图(UCG)特征,探讨UCG诊断心肌致密化不全的价值.方法 回顾性分析25例成人NVM患者的UCG表现,重点观察左、右心室壁的结构和运动,心功能的改变及各瓣膜的反流情况.结果 (1)25例NVM患者二维UCG表现为病变部位心肌见多发、过度隆突的肌小梁和深陷其间的隐窝,形成网状结构;彩色多普勒可探及小梁间深陷隐窝内有血流灌注并与心腔交通.(2)根据NVM累及部位,25例NVM患者中累及左心室23例,累及右心室2例,无一例累及双侧心室.(3)轻度NVM累及心室大小正常,收缩功能正常,中、重度NVM导致累及心室不同程度增大、收缩功能不同程度下降.(4)多数NVM合并病变侧房室瓣不同程度反流.(5)心功能不全20例,左室射血分数(LVEF)为(34±4)%;心功能正常5例,LVEF为(65±5)%.结论 成人NVM的UCG具有特征性表现,可以将UCG检查作为NVM特异性的诊断方法.     

现代影像学技术评价心肌运动同步化的临床研究进展

心力衰竭患者普遍存在不同程度的心室内或心室间的不同步运动,现代影像学尤其是超声心动图新技术在评估心脏机械不同步运动的部位、范围及程度等方面日益发挥着重要作用。本文着重介绍了超声心动图新技术包括组织多普勒、斑点追踪、速度向量成像和实时三维超声在评价心肌运动的同步性方面的研究和应用进展。     

胎儿超声心动图检测技术的临床应用

胎儿心脏异常是严重影响宫内胎儿生长发育及活产新生儿生存能力的严重先天性疾病之一,在胎儿畸形中的发生率较高,约占活产新生儿的5‰～ 8‰左右.胎儿心脏异常可分为结构异常和心律异常两大类.胎儿心脏异常形成复杂、种类繁多.近 20年来,先天性心脏病的救治水平有了很大的提高,但一部分手术后存活者,仍具有较高的病死率.而有些心脏异常为不可矫治的致死性畸形,发现后难以进行处理.     

超声心动图检测无症状糖尿病患者的左心功能

探讨无症状糖尿病的左心功能。方法：应用超声心动图测定无症状糖尿病患者及正常人的左心功能。结果：患者的左心中射血分数,短轴缩短率和心排血指数均较正常组降低,舒张功能中除左室晚期充盈血流峰值外,其余指标两组间差异均有显著性。结论无症状糖尿病患者心肌功能已有损害。     

彩色多普勒超声与磁共振成像诊断主动脉夹层的对比

目的：比较彩色多普勒超声心动图与磁共振成像（ＭＲＩ）对主动脉夹层（ＡＤ）的诊断价值。方法：应用彩色多普勒超声心动图及ＭＲＩ对１８例疑诊ＡＤ的患者进行检查。结果：超声心动图对ＡＤ的诊断可靠，二维超声能清楚观察到内膜片及真、假血管腔；彩色多普勒能直接观察血流由撕裂口进入假腔以及真、假腔内血流的变化，并能评价主动脉瓣返流程度；但有时胸段主动脉夹层图像欠清晰。ＭＲＩ对各型ＡＤ均能准确定位并分型，但检查费时长，危重患者及携带起搏器或其它金属治疗装置的患者不宜接受该检查。结论：彩色多普勒超声心动图与ＭＲＩ对诊断ＡＤ各有优缺点，临床医生根据实际情况选用或两者结合运用，对大多数病例可达到确诊目的。     

多普勒组织成像联合多巴酚丁胺药物负荷试验检测存活心肌的实验研究

目的 运用多普勒组织成像(Doppler tissue imaging,DTI)结合小剂量多巴酚丁胺负荷试验(low-dose dobutamine stress echocardiography,LDDSE)的方法检测存活心肌,并将结果与存活心肌的组织病理切片染色结果进行一致性比较,以评价该方法临床应用的可行性.方法 选取12只健康小型猪作为实验的研究对象.行冠状动脉造影后球囊堵塞左回旋支分支制作急性心肌梗死模型.制作心肌梗死模型前后各阶段均进行超声心动图检查,使用DTI速度模式,采用两级多巴酚丁胺负荷试验.应用16节段半定量分析室壁运动,选取静息状态下室壁运动异常的心肌节段进行存活性的评价.堵塞90 min后撤除球囊,10%KCl静注处死小型猪,TTC染色后进行结果对比.结果 ①12只猪用超声心动图静息DTI检测192个室壁节段,共检出26个运动异常节段.②行DTI结合LDDSE检测,上述26个运动异常节段中有16个节段运动改善,提示为存活心肌节段(A组).余10个节段无变化,为坏死心肌(B组).③DTI结合LDDSE试验诊断存活心肌与组织切片TTC染色结果相比较,其敏感性为92.9%,特异性为75%.结论 DTI结合小剂量多巴酚丁胺负荷试验是评价心肌存活性的一项超声新技术,因此有较好的临床应用前景.     

低剂量多巴酚丁胺负荷超声心动图评价急性心肌梗死存活心肌的研究

目的:研究低剂量多巴酚丁胺负荷超声心动图(LDDSE)对存活心肌的预测价值和安全性。方法:选择12例急性心肌梗死患者于发病后(7.5±1.0)天进行LDDSE试验,应用16节段半定量法分析室壁运动,选取静息状态下低动力或无动力的33个心肌节段进行存活性的评价;急性心肌梗死1个月后,患者复查超声心动图。结果:LDDSE检测存活心肌的敏感性、特异性、阳性预测值、阴性预测值及准确性分别85.7%868.5%866.7%886.7%及75.8%;在LDDSE过程中有2例患者因心电图示ST段抬高和1例患者因频发室早而停药,未见严重不良反应。结论:LDDSE可应用于急性心肌梗死患者存活心肌的评估,并能预测左室局部功能的改善,是一种较为安全、简便的评价存活心肌的无创性技术。     

多巴酚丁胺负荷心肌声学造影探测冠状动脉狭窄

目的 评价多巴酚丁胺负荷心肌声学造影（MCE）诊断冠脉狭窄的准确性。方法 在慢性冠脉狭窄闭胸犬模型上同步进行MCE和放射性微球测定心肌血流量（MBF）。结果 负荷状态时,异常冠脉供血区（MBF储备<3）呈现灌注缺损,峰值声强度（VI）较正常冠脉供血区低（33±13与48±14,P<0.01）,且异常和正常冠脉供血区峰值VI比值与相应MBF比值呈良好的线性正相关（r=0.86,P<0.0001）。结论 多巴酚丁胺可作为一种负荷药物用于MCE评价冠脉狭窄。     

多巴酚丁胺超声心动图负荷试验与放射性核素心肌灌注显像对心肌存活性的对比研究

目的:评价小剂量多巴酚丁胺超声心动图负荷试验(DSE)和放射性核素心肌灌注显像(SPECT)预测心肌存活性的价值。方法:以15例成功的PCI患者术后6个月室壁运动改善为检验标准,进行小剂量多巴酚丁胺超声心动图负荷试验及SPECT检查,比较两者检测心肌存活性的准确性。结果:DSE峰剂量期与低剂量期在预测心肌存活敏感性、阴性预测准确性方面差异具有统计学意义;与DSE相比,SPECT具有较高的敏感性但其特异性较低。结论:在预测心肌存活性的价值方面,DSE和SPECT各有优缺点,但DSE更具实用性。     

Evaluation of Myocardial Viability after Myocardial Infarction with Intravenous Real-time Myocardial Contrast Echocardiography

The myocardial viability after myocardial infarction was evaluated by intravenous myocardial contrast echocardiography. Intravenous real-time myocardial contrast echocardiography was performed on 18 patients with myocardial infarction before coronary revascularization. Follow-up echocardiography was performed 3 months after coronary revascularization. Segmental wall motion was assessed using 18-segment LV model and classified as normal, hypokinesis, akinesis and dyskinesis. Viable myocardium was defined by evident improvement of segmental wall motion 3 months after coronary revascularization. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions： homogeneous opacification; partial or reduced opaciflcation or subendocardial contrast defect; contrast defect. The former two conditions were used as the standard to define the viable myocardium. The results showed that 109 abnormal wall motion segments were detected among 18 patients with myocardial infarction, including 47 segments of hypokinesis, 56 segments of akinesis and 6 segments of dyskinesis. The wall motion of 2 segments with hypokinesis before coronary revascularization which showed homogeneous opacification, 14 of 24 segments with hypokinese and 20 of 24 segments with akinese before coronary revascularization which showed partial or reduced opaciflcation or subendocardial contrast defect was improved 3 months after coronary revascularization. In our study, the sensitivity and specificity of evaluation of myocardial viability after myocardial infarction by intravenous real-time myocardial contrast echocardiography were 94.7% and 78.9%, respectively. It was concluded that intravenous real-time myocardial contrast echocardiography could accurately evaluate myocardial viability after myocardial infarction.     

心肌对比超声评价多巴酚丁胺对冠状动脉微循环的直接效应:与腺苷对比

目的 评价多巴酚丁胺对正常和狭窄冠状动脉微循环的直接效应.并与腺苷对比.方法 实验应用9条健康杂种犬,制备左前降支静息无血流限制性狭窄.在静息状态和左冠状动脉主干内连续输注多巴酚丁胺(2mg·kg-1·min-1)和腺苷(5 mg·kg-1·min-1)时,进行间断谐波心肌对比成像评估心肌血流容积(A)和心肌血流速度(b),并同步应用放射性标记微球测定心肌血流量(MBF).计算心率血压乘积和心肌血管阻力(MVR).结果 两种药物引起正常和狭窄冠状动脉供血区MBF明显增加和MVR明显降低(P<0.05).在正常冠状动脉供血区,腺苷对A无明显影响.MVR的降低完全是阻力血管的扩张所致(99%),MBF增加主要是由于b的加快(△β/△A=13.6);多巴酚丁胺可引起部分A增加(28%),使总MVR降低中的32%来自这种毛细血管征募,但MBF增加主要还是由于b的加快(△β/△A=5.9).在狭窄冠状动脉供血区,两种药物引起MBF增加的程度相同,MBF增加均完全是由于b的加快;多巴酚丁胺和腺苷引起毛细血管的关闭分别导致14%和15%心肌毛细血管阻力的增加.结论 经冠状动脉内直接给药物时,多巴酚丁胺对冠状动脉微循环的直接效应与腺苷对冠状动脉微循环的直接效应非常相近,MBF增加主要由于心肌血流速度的增快所致.     

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     

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     

Estimation of coronary artery stenosis by low-dose adenosine stress real-time myocardial contrast echocardiography: a quantitative study

Background  Coronary microcirculation reserve is an important field in the research of coronary artery disease, but it is difficult to identify clinically. Currently it is widely accepted that myocardial contrast echocardiography (MCE) is a safe, inexpensive method and has comparatively high image resolution. The present study used quantitative low-dose adenosine stress real-time (RT)-MCE to estimate myocardial perfusion and the coronary stenosis.

Methods  Forty-nine left ventricular (LV) segments from 14 unselected patients were divided into three groups according to the coronary angiography or CT angiography results: group 1 (n=20, 41%) without significant stenosis (<70%), group 2 (n=12, 24%) with successful percutaneous coronary intervention (PCI), and group 3 (n=17, 35%) with significant stenosis (>70%). RT-MCE was performed in these patients with low-dose adenosine stress and continuous infusion of Sonovue. The replenishing curves were drawn according to the contrast density measured at the end-diastolic frame of every cardiac circle by ACQ software.

Results  Forty-nine LV segments with satisfactory image quality were picked for quantitative contrast echo analysis. The replenishing curves were analyzed at baseline and after stress. Perfusion of group 3 did not decrease significantly at baseline, and showed no improvement during adenosine stress and was significantly different from groups 1 and 2 (P <0.05). The A·β and β increased more significantly in group 1 than in groups 2 and 3 (P <0.05). In a receiver operating characteristic (ROC) curve analysis, A·β under adenosine stress <1.74 dB/s had a sensitivity and specificity of 71% for diagnosis of coronary artery stenosis, reduced adenosine-induced rise (percentage of A·β <81%) had a sensitivity and specificity of 83% and 79% for the diagnosis of low-reserve, and β <54% had a sensitivity of 86% and specificity of 79%.

Conclusions  Rest perfusion of severely stenosed arteries may be normal, but adenosine stress can detect the impaired perfusion reserve. Low-dose adenosine stress RT-MCE provides good accuracy for the evaluation of coronary perfusion reserve and hence coronary stenosis.

     

2D TOF与3D CE MRV在3.0T磁共振脑静脉窦成像应用比较

目的：比较2D TOF与3D CE MRV在3.0T磁共振脑静脉窦成像中应用价值。方法：45例患者在3.0T磁共振行颅脑常规MRI、2D TOF及3D CE MRV,由两名高年资神经放射学医生评价两种MRV序列对上矢状窦、下矢状窦、直窦、横窦及乙状窦的解剖结构及病变的显示能力。结果：10例（22.2%）患者在2D和3D CE MRV上均清晰显示各静脉窦的正常解剖形态及信号;2例（4.4%）患者在3D CE MRV上静脉窦增强信号较差而在2D TOF MRV上显示良好;33例（73.3%）患者在2D TOF MRV上静脉窦解剖结构及病变的显示差于3D CE MRV,包括10例正常静脉窦、3例一侧横窦发育不良、1例一侧横窦闭锁、16例静脉窦血栓、3例颅内脑膜瘤。结论：在3.0T磁共振,2D TOF可作为MRV首选序列,但是,当2D TOF MRV上见到静脉窦信号或管径大小异常时,应增加3D CE MRV序列以进一步明确诊断。