多普勒组织声像图与解剖M型超声心动图的对比研究

目的　探讨多普勒组织声像图 (DTI)与解剖M型超声心动图对冠心病病变段诊断的异同。方法　本文对2 8例经冠脉造影 (CAG)确诊的冠心病用频谱勒组织声像图(DT PW )测定其室壁运动频谱 ,以收缩波S≤ 5cm/s为病变节段 ,用解剖M型法测定收缩期室壁增厚率 ,以 <30 %为病变节段 ,两种方法均和CAG证实的病变节段对比。结果　DTI法诊断冠心病病变段敏感性为 74 6 0 % ,解剖M型法39 6 8% ,病变段收缩波 (S)低平 ,时相延迟 ,方向相反或频谱紊乱 ,后两种情况多见于梗死节段 ;室壁增厚率降低 ,甚至为负数。结论　DTI法对冠心病的诊断较解剖M型法敏感 ,可成为诊断冠心病的一种辅助方法。     

多普勒组织成像技术在心肌梗死心功能评价中的应用

目的:研究多普勒组织成像(DTI)技术评价心肌梗死的临床应用价值。方法:回顾性分析应用DTI及彩色多普勒超声心动图(UCG)检查30例急性心肌梗死(AMI)患者的资料。结果:①AMI后2周,3个月,6个月时左室舒张功能显著减退(P<0.01),而左室收缩功能在2周时显著降低(P<0.01),随时间的推移略有改善;②AMI患者DTI速度图显像能更直观反应梗死相关局部的心肌室壁病变;③AMI患者2周时DTI频谱图特征:收缩波,舒张早期波E波和E／A(舒张晚期波)振幅比值降低(P均<0.01)。结论:DTI技术为观察AMI后心肌的室壁运动,心脏的收缩和舒张功能提供了一个直观,而且重复性好的有效方法。     

组织多普勒成像技术与冠状动脉造影对照评价冠心病心肌缺血的研究

目的:采用组织多普勒成像技术(TDI)定量测定冠心病心肌缺血患者的左心室各节段室壁运动速度,以评价左心室局部心肌的功能。方法:随机入选因胸痛住院并行冠状动脉(冠脉)造影的患者81例,通过冠脉造影确定冠心病组患者45例(冠脉狭窄≥50％),其余为对照组患者36例(冠脉狭窄<50％)。所有患者在行冠脉造影检查前均行普通超声心动图检查和左心室各室壁节段心肌组织多普勒成像技术(TDI)检查,分别比较结果。结果:冠心病组各节段室壁的收缩速度(Vs)较对照组无明显降低,舒张晚期运动峰速度(Va)两组比较无明显差异, 而舒张早期运动峰速度(Ve)及Ve与Va的比值均显著低于对照组相应节段。以冠脉狭窄≥70％为标准,按病变血管的种类分别与对照组相应节段心肌进行比较,不同部位严重狭窄的冠心病患者Vs、Ve及Ve／Va与对照组比较均有显著性差异(P<0．05)。结论:①冠心病组左心室局部心肌舒张功能异常的出现早于局部心肌收缩功能异常,TDI直观、定量显示左心室早期局部心肌舒张功能异常。②TDI亦能测定左心室局部心肌中严重缺血的心肌节段收缩功能异常。     

应用多普勒组织成像技术观察曲美他嗪对冠心病左心室局部收缩和舒张功能的影响

目的观察曲美他嗪(trimetadine,TMZ)对冠心病左室局部收缩和舒张功能的影响,并评价多普勒组织成像技术(DTI)在研究药物改善局部心肌功能中的价值.方法42例冠心病患者,随机分为两组.对照组20例,服用硝酸异山梨酯+钙通道阻滞剂+阿司匹林;TMZ组22例,在上述药物基础上加用TMZ.应用DTI技术测量两组服药前后左室壁12个节段收缩期峰值速度(VS),和舒张早期峰值速度(VE).并计算12节段心肌平均收缩峰值速度(VS)和舒张早期峰值速度(VE).结果(1)TMZ组用药后室壁12节段中,有7个节段的VS和VE显著升高(均P＜0.05),对照组治疗前后比较VS和VE差异无显著性.(2)VS和VE在TMZ组治疗后,分别由(3.94±1.26)cm/s升高至(4.78±1.30)cm/s(P＜0.05);(4.15±1.33)cm/s升高至(5.04±1.37)cm/s,均P＜0.05.(3)TMZ组治疗后运动异常节段的恢复数显著高于对照组(P＜0.0).结论(1)TMZ可改善冠心病患者的左室局部收缩和舒张功能.(2)DTI能够定量分析冠心病缺血心肌对药物治疗前后室壁运动的变化,对指导临床用药有一定应用价值.     

定量组织速度成像技术评价冠心病患者冠状动脉病变的价值

目的探讨定量组织速度成像(QTVI)技术评价冠心病患者冠状动脉病变的价值。方法选择经冠脉造影诊断为冠心病的患者41例,根据冠脉造影结果将所有患者左心室各节段分为无病变、轻度病变、中度病变和严重病变节段4组,应用组织多普勒定量组织速度成像技术,测定所有患者在静息和潘生丁负荷状态下左心室各节段室壁运动变化,并与冠脉造影所得的结果相比较。结果冠脉病变节段的平均收缩期运动速度(Vs)较正常节段减低,舒张早期充盈速率(Ve)和舒张晚期充盈速率(Vs)比值<1,节段心肌等容舒张时间(RIVRT)延长。结合潘生丁负荷试验可使这些变化更明显,以冠脉造影结果为标准,其判断血管病变敏感性为93.7%,特异性为86.4%。结论定量组织速度成像技术检测左心室各节段心肌功能变化,可用来评价冠心病患者冠状动脉病变,结合潘生丁负荷试验,可提高判断的敏感性和特异性。     

多普勒组织成像测定二尖瓣环运动速度评价急性心肌梗死后患者左心室功能

目的 :应用多普勒组织成像 (DTI)技术测定二尖瓣环运动速度 ,定量分析急性心肌梗死后患者左心室收缩和舒张功能。方法 :研究对象为 6 1例确诊首次急性心肌梗死的患者和 2 0例正常人。常规行超声心动图检查及DTI技术测定二尖瓣环运动速度频谱。记录心尖四腔、心尖二腔和心尖长轴切面多普勒组织成像二尖瓣环运动速度。测定二尖瓣环运动速度参数包括 :二尖瓣环收缩速度 (Sm) ,二尖瓣环舒张早期速度 (Em) ,二尖瓣环舒张晚期速度 (Am) ,二尖瓣环舒张早期速度的比值 (E Em)。结果 :与对照组相比 ,急性心肌梗死后患者DTI可敏感地显示出二尖瓣环收缩和舒张运动速度显著下降(P <0 0 5 ) ;E Em也有显著差别 (P =0 0 13)。DTI二尖瓣环收缩速度与二尖瓣环舒张早期速度之间 ,二尖瓣环收缩速度与左心室射血分数和室壁运动积分之间存在显著的相关性。平均二尖瓣环收缩期速度≥ 8 9cm s预测射血分数 (EF)≥ 5 5 %的敏感性、特异性分别为 88 2 %、70 % ,准确率为 81 5 %。结论 :DTI测量二尖瓣环运动速度 ,作为定量检测急性心肌梗死患者近期心脏功能状态的新方法 ,具有一定的应用价值。     

多普勒组织成像技术对冠心病患者左心功能的评估

2001年5月至2003年7月，我们应用多普勒组织成像(DTI)技术对一组冠心病患者及正常人二尖瓣环6个节段运动速度进行检测，旨在探讨DTI无创性诊断冠心病的临床应用价值。现报告如下。     

定量组织速度成像对左心室心肌运动异常的研究

目的探讨定量组织速度成像(QTVI)技术检测冠心病节段性室壁运动异常的临床应用价值。方法应用QTVI技术对136例经选择性冠状动脉造影证实为冠心病(冠心病组)和83例年龄匹配的正常人(对照组)的左心室壁各节段运动速度进行测量,并与常规超声心动图的检查结果进行对照分析。结果冠心病组室壁运动异常节段的峰值速度与对照组相应节段比较均明显减低,运动频谱异常的特点为波幅减低、时相延迟、方向改变或频谱紊乱等。结论QTVI可直观、定量显示左心室节段性室壁运动异常,是一种诊断冠心病的无创伤性方法,具有重要的应用价值。     

应用组织多普勒成像技术对前壁心肌梗死左心室舒张功能的诊断研究

目的应用组织多普勒成像技术(DTI)诊断前壁心肌梗死左心室舒张功能。方法陈旧性前壁心肌梗死组患者45例,对照组健康成年人42例。均行二维超声心动图及DTI检查。结果心肌梗死组与对照组DTI测值比较:心肌梗死组梗死节段收缩期波峰值速度(Vs),舒张早期波峰值速度(Ve)明显低于对照组。二尖瓣环DTI心肌梗死组舒张期早期速度(Ea)明显低于对照组,而舒张晚期速度无显著差异。结论DTI为定量分析左心室舒张功能提供了有效检测手段。     

脉冲多普勒组织成像早期定量诊断冠心病心肌缺血的临床研究

目的应用多普勒组织成像（明）技术对冠心病（cAD）患者室壁运动速度进行研究。方法用脉冲DTI检测45例CAD患者及35例健康对照组的左室6个室壁，12个节段的运动频谱，分别测量其收缩期峰值速度（VS）、舒张早期峰值速度（VE）；同时以二维超声心动图观察CAD患者上述左室各节段室壁运动情况。结果与健康对照组相比，CAD组心室各节段VS、VE减小明显（P〈0．05，P〈0．01）。而二维超声心动图观察结果，45例CAD患者室壁运动正常、可疑异常及异常者分别为10例（22％）、4例（8％）及31例（70％）。结论DTI可在常规二维超声心动图检测异常之前无创、定量诊断心肌缺血。     

Usefulness of pulse-wave Doppler tissue sampling and dobutamine stress echocardiography for identification of false positive inferior wall defects in SPECT

False positive inferior wall perfusion defects restrict the accuracy of SPECT in diagnosis of coronary artery disease (CAD). Pulse-Wave Tissue Doppler (PWTD) has been recently proposed to assess regional wall motion velocities. The objectives of this study were to evaluate the presence of CAD by using PWTD during dobutamine stress echocardiography (DSE) in patients with an inferior perfusion defect detected by SPECT and compare PWTD parameters of normal cases with patients who had inferior perfusion defect and CAD. Sixty-five patients (mean age 58 +/- 8 years, 30 men) with a normal LV systolic function at rest according to echocardiographic evaluation with an inferior ischemia determined by SPECT and a control group (CG) of 34 normal cases (mean age 56 +/- 7 years, 16 men) were included in this study. All patients underwent a standard DSE (up to 40 microg / kg / min with additional atropine during sub-maximum heart rate responses). Pulse-wave Doppler tissue sampling of inferior wall was performed in the apical 2-chamber view at rest and stress. The coronary angiography was performed within 24 hours. The results were evaluated for the prediction of significant right coronary artery (RCA) and / or left circumflex coronary artery (CX) with narrowing (> or = 50% diameter stenosis, assessed by quantitative coronary angiography). It was observed that the peak stress mean E / A ratio was lower in patients with CAD when compared to patients without CAD (0.78 +/- 0.2 versus 1.29 +/- 0.11 p < 0.0001). Also the peak stress E / A ratio of normal cases was significantly higher than patients who had CAD (1.19 +/- 0.3 versus 0.78 +/- 0.2 p < 0.0001). When the cut off point for the E / A ratio was determined as 1, the sensitivity and specificity of dobutamine stress PWTD E / A were 89% and 86 %, respectively. The peak stress E / A ratio was higher than 1 in all patients with a false positive perfusion defect. Systolic S velocity increase during DSE was significantly lower in patients with CAD (54 % +/- 17 versus 99 % +/- 24 p = 0.01). The analysis of S velocity increase yielded 81% sensitivity and 76 % specificity for prediction of CAD when a 70 % increase was accepted as a cut-off value. Pulse-wave Doppler tissue sampling during DSE may help to identify false positive inferior wall defects detected by SPECT.     

多普勒组织成像检测冠心病患者梗死心肌的研究

目的　测算比较正常室壁心肌和梗死心肌的运动速度 ,评估多普勒组织成像 (DTI)对冠心病梗死心肌的诊断价值。方法　心肌梗死患者 4 6例 ,分成前壁梗死组 2 9例和下壁梗死组 17例 ,健康人 4 8例作对照 ;在心尖左室长轴切面 (alax)上测得室壁节段厚度 ;于心尖四腔心切面(ap4cv)、心尖二腔心切面 (ap2cv)、胸骨旁左室长轴切面(pslax)和alax应用DTI ,按左室壁 16节段 ,测量各室壁节段心肌运动曲线的速度指标 :收缩期峰值运动速度 (Sm) ;舒张早期峰值运动速度 (Em) :收缩期峰值速度梯度 (PVGs) :舒张早期峰值速度梯度 (PVGe) :收缩期跨壁速度梯度 (MVGs) :舒张早期跨壁速度梯度 (MVGe) ,并分别作组间和组内比较。结果　 (1)心梗患者内膜下心肌绝大多数节段性的室壁运动速度降低 ,与对照组存在显著差异 (P <0 0 1或 <0 0 5 ) :(2 )前壁梗死患者前间隔峰值速度梯度 (PVG)与跨壁速度梯度、(MVG)降低 ,中间段明显降低 (P <0 0 1或 <0 0 5 ) ,后壁基底段的MVGs 显著升高 (P <0 0 5 ) ;前间隔PVG、MVG明显小于后壁 (P <0 0或 <0 0 5 ) ;(3)下壁梗死患者各室壁节段舒张早期峰值速度梯度 (PVGe)除后壁基底段外均降低 ;同水平节段内膜下心肌峰值运动速度 (Sm、Em)趋于一致。结论　梗死心肌运动速度明显低于正常     

Relation of ultrasonic tissue characterization with integrated backscatter to contractile reserve in patients with chronic coronary artery disease

BACKGROUND: Previous studies have shown that viable but stunned myocardium displays contractile reserve and exhibits cardiac cycle-dependent variations of integrated backscatter (CVIB), whereas infarcted myocardium does not. HYPOTHESIS: This study was designed to clarify whether assessment of the acoustic properties of the myocardium can predict contractile reserve in patients with chronic coronary artery disease (CAD). METHODS: In all, 21 patients with chronic CAD and 19 normal control subjects were studied. The magnitude of CVIB of the myocardium was measured in the basal and mid segment of the anterior septum and posterior wall of the left ventricle, using a real-time, two-dimensional integrated backscatter imaging system. The results were compared with the percent systolic wall thickening and the wall motion before and after revascularization. The wall motion was graded as normal, hypokinetic, or akinetic, and contractile reserve was considered present when an akinetic or hypokinetic segment improved after revascularization. RESULTS: The average magnitude of CVIB was lower among dysfunctional segments of CAD than among normal segments of controls (3.73 +/- 1.71 vs. 6.35 +/- 0.69, p < 0.001). Of the 77 segments examined, 38 showed reversible dysfunction. Before revascularization, percent systolic wall thickening was similar among segments showing contractile reserve compared with those with persistent dysfunction myocardium (17.97 +/- 8.41 vs. 16.83 +/- 6.37%, p = 0.19), and the mean CVIB was significantly greater in segments with than in those without contractile reserve (4.73 +/- 1.47 vs. 2.75 +/- 1.31, p < 0.001). The CVIB above 3 dB before percutaneous transluminal coronary angioplasty predicted segments with contractile reserve with a sensitivity and specificity of 84.2 and 79.5%, respectively. CONCLUSIONS: Cardiac cycle-dependent variations of integrated backscatter reflected myocardial contractility and functional capacity of the myocardium. They predicted segmental contractile reserve in patients with CAD.     

Asynchronie der ventrikulären Kontraktion und Relaxation — Pathophysiologisch erkanntes Phänomen, jetzt klinisch nachweisbar

When regional myocardial dysfunction is present, the physiological pattern of ventricular filling and contraction is impaired. During acute coronary occlusion, characteristic changes are observed in the ischemic myocardial segment: the amplitude of the systolic wall thickening is reduced (hypokinesia), then virtually absent (akinesia) and finally replaced by a paradoxical outward motion (dyskinesia). The maximum amplitude is reached in early diastole ("post-ejection thickening"). Since hyperkinesis develops in the normal region, the ischemic and the normal region contract asynchronously. Experimentally left ventricular asynchrony can be detected by means of subendo- and subepicardially implanted ultrasonic crystals ("sonomicrometry") or by the analysis of the phase difference of the first Fourier harmonic of dysfunctional versus control myocardial wall motion. In the clinical setting, digitized cineventriculography, radionuclide angiography and digitized M-mode echocardiography were used to assess left ventricular asynchrony in patients with coronary artery disease and hypertrophic cardiomyopathy. However, these imaging modalities are time-consuming and require complicated off-line analysis. Tissue Doppler echocardiography (TDE) is a new ultrasound modality that is based on color Doppler principles and allows for quantification of myocardial wall motion velocity by detection of consecutive phase shifts of the ultrasound signal reflected from the myocardium. The Doppler signals are displayed as a color or pulsed Doppler image by rejecting low-amplitude echoes from the blood pool due to changes in thresholding and filtering algorithms. In addition, the ability to measure low velocity is improved in the TDE system so that the lowest measurable velocity is 0.2 cm/s, a velocity level associated with cardiac tissue motion (Table 1). Due to its high temporal and spatial resolution, TDE provides valuable information on regional myocardial wall motion during different intervals of the cardiac cycle. In healthy subjects, patients with coronary artery disease and patients with hypertrophic cardiomyopathy, tissue Doppler echocardiography was used to assess myocardial synchrony/asynchrony on a 2-fold temporal and spatial analysis. Peak myocardial velocities in different myocardial regions were detected during rapid ejection, isovolumic relaxation, rapid filling and atrial contraction (Figure 1). In the apical view, during the isovolumic relaxation time (IVRT) healthy subjects showed slow, synchronous outward motion of the septum and the lateral wall with homogeneous color-encoding (blue/green, Figure 2). Analysis of peak velocities revealed low, negative velocities in both the septum and the lateral wall (Figure 3). In patients with a significant luminal narrowing of the LAD myocardial asynchrony was detected during the isovolumic relaxation period: while the septum was moving inwards (red color-encoding with low, positive velocities), the lateral wall was moving outwards (blue/green encoding, low, negative velocities). A representative example of a patient with CAD is given in Figure 4. The M-mode analysis of the abnormally contracting interventricular septum reveals positive peak tissue velocities during the isovolumic relaxation period (Figure 5). In hypertrophic cardiomyopathy, TDE was able to detect an abnormal inward motion of the interventricular septum during IVRT and a delay in the onset of rapid filling (Figure 6). Thus, tissue Doppler echocardiography is a feasible method for the on-line detection of myocardial asynchrony. Sensitivity and specificity of the findings have to be explored in further, prospectively randomized trials.     

Mechanisms of reduced left ventricular filling rate in coronary artery disease.

To identify mechanisms underlying slow left ventricular filling in coronary artery disease, left ventriculograms from 93 patients and 18 normal subjects were digitised frame by frame and global and regional function analysed. In 54 patients peak normalised filling rates were above the lower 95% confidence limit of normal (2 X 9s-1) and in 39 they were below. Patients with slow filling had a lower ejection fraction, a higher end systolic volume, and less overall shape index change, although a larger percentage occurred during isovolumic relaxation owing to asynchronous relaxation. Stroke volume was not significantly different. Slow outward wall motion was associated with increased cavity volume and systolic hypokinesis. Wall motion was also appreciably asynchronous, with wide spreads in the times of peak outward velocity and termination of rapid outward movement between regions. Early outward movement usually started in the anterior region, with peak velocity occurring before mitral valve opening, and significantly earlier than that in the apex or the inferior region. Ventricular oscillations occurred during filling in 23 patients. This asynchronous wall movement was unrelated to the distribution of coronary artery disease, systolic hypokinesis, or Q waves on electrocardiograms but was similar to that occurring in mitral stenosis. The main causes of slow left ventricular filling in patients with coronary artery disease appear to be (a) failure to achieve a normal low end systolic volume, with associated loss of physiological changes in left ventricular cavity shape, and (b) incoordinate wall motion during isovolumic relaxation which dissipates energy normally coupled to rapid ventricular filling. The resulting slow and asynchronous wall motion may have clinical implications especially when the time available for left ventricular filling is short.     

用多普勒组织成像评价冠状动脉狭窄患者右室舒张功能

目的 :应用多普勒组织成像 （DTI）技术评价冠状动脉狭窄患者右室整体舒张功能的变化。方法 :测定三尖瓣环的运动速度及各舒张功能参数。结果 :单纯左冠状动脉狭窄组右室舒张功能均减低 ,混合支冠状动脉狭窄组右室舒张功能较单纯左支冠脉狭窄组进一步减低。结论 :DTI评估冠状动脉狭窄患者的右室舒张功能有一定的临床应用价值     

Anatomic and functional significance of a hypotensive response during supine exercise radionuclide ventriculography

The significance of a decline in systolic blood pressure (BP) during supine exercise was examined in 820 patients who underwent both supine exercise gated equilibrium radionuclide ventriculography and coronary angiography. Twenty-seven patients, 3% of the study population, had a decrease in systolic BP at peak exercise of more than 10 mm Hg from the systolic BP at rest. Other indicators of ischemia--angina, ST-segment depression, a decrease in ejection fraction and wall motion abnormality during exercise--were present frequently but not uniformly in these patients. Although most patients had a decline in ejection fraction and a new wall motion abnormality with exercise, 4 patients had an increase in ejection fraction with exercise without any regional wall motion abnormalities. Coronary angiography in the 27 patients with systolic hypotension demonstrated severe coronary artery disease (CAD). Twenty-two patients (81%) had 3-vessel or left main CAD. Twenty of these 22 patients with 3-vessel CAD had at least 2 arteries with 90% or more diameter stenoses. Systolic hypotension during supine exercise radionuclide angiography is infrequent, usually associated with evidence of global and regional left ventricular dysfunction, and a marker of very severe CAD.     

Identification of hemodynamically significant coronary artery stenoses by dipyridamole-magnetic resonance imaging and99mTc-methoxyisobutyl-isonitrile-SPECT

Magnetic resonance imaging (MRI) has been used in conjunction with dipyridamole induced wall motion abnormalities for the noninvasive detection of coronary artery disease (CAD). To assess the clinical usefulness of dipyridamole-MRI for the localization of CAD and to evaluate the relation between dipyridamole induced wall motion abnormalities and myocardial perfusion 33 patients with severe CAD (>70% diameter reduction) underwent MRI at rest and after dipyridamole infusion (0.75 mg dipyridamole/kg over a period of 10 minutes). All patients performed exercise stress testing and 20 patients of the study group additionally had rest and exercise stress^99mTc-methoxyisobutyl-isonitrile-SPECT (MIBI-SPECT). Two patients (6%) could not be evaluated due to severe motion artifacts during dipyridamole MRI.Segmental wall motion and perfusion of corresponding short axis planes were related to the major coronary arteries using a standardized segmental coronary artery perfusion pattern. Detection of wall motion abnormalities or perfusion defects by 2 blinded observers in consensus was the criterion for grading a segment normal or pathologic. For localization of CAD, segmental gradings were related to the presumed coronary artery territories.Stress-ECG was pathologic in 19/31 patients yielding a sensitivity of 61% and dipyridamole induced angina was present in 68% (21/31) of patients. Dipyridamole-MRI detected coronary artery disease with a sensitivity of 84% (26/31 patients) and all patients with new wall motion abnormalities also had dipyridamole induced angina. For the subgroup of 20 patients with MIBI-SPECT images, CAD was detected by both MIBI-SPECT and Dipyridamole-MRI in 90% (18/20) of patients. Dipyridamole-MRI and MIBI-SPECT gradings agreed in 55/60 (92%) coronary artery perfusion territories. There were no significant differences with respect to the sensitivities of Dipyridamole-MRI/MIBI-SPECT for the localization of individual coronary artery stenoses yielding 81%/78% for left anterior descending, 80%/80% for left circumflex and 92%/89% for right coronary artery stenoses. However, specificity of Dipyridamole-MRI (89%) for the detection of RCA stenoses was slightly better than for MIBI-SPECT (80%).Dipyridamole-MRI induced regional wall motion abnormalities proved to be a highly sensitive parameter for the non-invasive localization of CAD. The similarity of dipyridamole-MRI and MIBI-SPECT results suggests a close agreement between functional and perfusion parameters in the assessment of hemodynamically significant coronary artery stenoses. The clinical utility of this MRI stress test is still limited by high cost and long imaging times which may, however, be overcome by the development of new shorter imaging sequences.Abbreviations CAD coronary artery disease - MRI magnetic resonance imaging - MIBI-SPECT 99mTc-methoxyisobutyl-isonitrile-SPECT     

彩色多普勒心肌组织显像测定小儿左室收缩功能

用彩色多普勒心肌组织显像（ＤＴＩ）测定２０３例不同年龄正常小儿和３９例病毒性心肌炎、２３便扩张型心肌病患儿的二尖瓣环、左室后壁、室间壁、心尖部收缩期运动速度,明确了小儿正常值,并与其他检查左室收缩功能的指标进行比较。结果显示,ＤＴＩ测定心肌炎、心肌病患儿左室收缩功能降低的敏感性显著高于其他检查方法。     

R wave amplitude changes during stress testing. Comparison with ST segment depression and angiographic correlation

One-hundred and seven exercise stress tests and coronary angiograms were reviewed retrospectively, in order to evaluate the usefulness of R wave amplitude changes (ΔR) during exercise compared with ST segment depression in the screening of patients with coronary artery disease (CAD).We also attempted to correlate ΔR with the severity of CAD as expressed by coronary arteriography and left ventriculography.Thirty-six patients showed no coronary artery narrowing (0-V); the remaining 71 patients with stenosis of 70% of at least one of the major coronary arteries were divided into three groups.Sixteen patients had single vessel disease (1-V); five (31%) in this group showed abnormal left ventricular wall motion. Thirty-one patients had two-vessel disease (2-V); 22 (71%) of the 31 demonstrated abnormal left ventricular wall motion. Twenty-four patients had three-vessel disease (3-V); 20 (83%) of the 24 showed abnormal left ventricular wall motion.We considered ΔR values ≥ 0 and ST segment depression ≥ 1 mm. significant for diagnosis of CAD.The sensitivity of the ΔR method in predicting CAD was superior to the method based upon ST segment depression; however, the latter was significantly (P < .02) more specific than the former. The predictive accuracy of these two criteria was similar.We found ΔR values ≥ 0 more frequently in the 2-V and 3-V groups as compared with the 1-V group. Patients of the 2-V and 3-V groups had a significantly higher incidence of abnormal left ventricular wall motion (P < .01, P < .0002, respectively) in comparison with 1-V patients. Thus, ΔR values ≥ 0 during exercise stress testing are very likely related to left ventricular impairment.Even though the accuracy of the ΔR method was greater in more severe CAD, it seems to be offset by a concomitant decrease in specificity.