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1.
Real-time coherent contrast imaging (CCI) echocardiography has the ability to evaluate wall motion and myocardial perfusion simultaneously, but its clinical applicability in the diagnosis of coronary artery disease (CAD) remains to be determined. This study examines the level of agreement between real-time CCI echocardiography and thallium-201 single-photon emission computed tomography (SPECT) following stress vasodilation. Forty-two patients with known or suspected CAD underwent real-time CCI using octafluoropropane-filled microspheres infusion before and after dipyridamole and thallium-201 injections. The apical 4- and 2-chamber views were each divided into 6 segments to assess wall motion and perfusion. Real-time CCI and SPECT were interpreted independently. Thirty-eight patients successfully completed tests, and 4 had suboptimal contrast images. Each vascular territory was classified as normal or abnormal by CCI perfusion, wall motion, and SPECT at baseline and at stress. Of the 114 territories (3 in each of the 38 patients), 3 (3.5%) were not analyzed; however, all territories corresponding to the left anterior descending artery were suitable for analysis. Concordance between CCI echocardiography and thallium-201 SPECT perfusion for left anterior descending, left circumflex, and right coronary artery territories were 91%, 86%, and 69%, respectively; between CCI perfusion and wall motion, the correlations were 93%, 93%, and 91%, respectively. When CCI perfusion and wall motion analysis were combined, their concordance to thallium-201 SPECT uptake improved to 94%, 89%, and 79%, respectively. In conclusion, real-time CCI echocardiography agrees very closely with thallium-201 SPECT in assessing myocardial perfusion following vasodilatory stress. Assessment of myocardial perfusion, in addition to segmental wall motion analysis, during stress echocardiography may be a significant contribution to the noninvasive evaluation of patients with ischemic heart disease.  相似文献   

2.
Coronary artery disease is a leading cause of morbidity and mortality worldwide. Noninvasive imaging tests play a significant role in diagnosing coronary artery disease, as well as risk stratification and guidance for revascularization. Myocardial perfusion imaging, including single photon emission computed tomography and positron emission tomography, has been widely employed. In this review, we will review test accuracy and clinical significance of these methods for diagnosing and managing coronary artery disease. We will further discuss the comparative usefulness of other noninvasive tests—stress echocardiography, coronary computed tomography angiography, and cardiac magnetic resonance imaging—in the evaluation of ischemia and myocardial viability.  相似文献   

3.
Recent updates in the field of echocardiography have resulted in improvements in both image quality and techniques allowing echocardiography to maintain it's position as the primary non-invasive imaging modality. In particular, the development of new ultrasound contrast agents and imaging techniques have now made possible the assessment of myocardial perfusion. Myocardial contrast echocardiography utilises acoustically active gas filled microspheres (microbubbles), which have rheology similar to that of red blood cells. The detection of myocardial perfusion during echocardiographic examinations permits simultaneous assessment of global and regional myocardial structure, function, and perfusion, enabling the optimal non-invasive assessment of coronary artery disease. Myocardial contrast echocardiography is equally adept in assessing chronic coronary artery disease, acute coronary syndromes and hibernating myocardium.  相似文献   

4.
Myocardial perfusion single photon emission computed tomography (SPECT) is a widely utilized noninvasive imaging modality for the diagnosis, prognosis, and risk stratification of coronary artery disease. It is clearly superior to the traditional planar technique in terms of imaging contrast and consequent diagnostic and prognostic yield. The strength of SPECT images is largely derived from the three-dimensional, volumetric nature of its image. Thus, this modality permits three-dimensional assessment and quantitation of the perfused myocardium and functional assessment through electrocardiographic gating of the perfusion images.  相似文献   

5.
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.  相似文献   

6.
BACKGROUND: Gated single-photon emission computed tomography (gated SPECT) myocardial perfusion imaging allows the analysis of left ventricular (LV) perfusion and function during the same acquisition. RESULTS: Gated SPECT provides additional information to myocardial perfusion, which improves test specificity in patients with known or suspected coronary artery disease and hence diminishes the amount of borderline diagnosis. Because gated SPECT provides reliable information on LV ejection fraction and LV volumes, it is also a valuable tool in risk stratification. In addition, from gated SPECT, images can be reconstructed from which wall motion can be assessed showing a good correlation with wall motion assessed by accepted imaging modalities as echocardiography, magnetic resonance imaging, and contrast angiography. In the future wall motion analysis from gated SPECT may also be used for revascularization stratification. CONCLUSIONS: Gated SPECT gives important additional information beyond myocardial perfusion imaging alone, which could have major clinical implications for optimal patient management.  相似文献   

7.
BACKGROUND: Real-time myocardial contrast echocardiography (MCE) makes possible the simultaneous visualization of changes in perfusion imaging and wall motion. OBJECTIVES: To assess the accuracy of real-time MCE for detecting the presence and extent of coronary artery disease (CAD), and to evaluate the correlation between wall motion and myocardial perfusion by visual examination. METHODS: A total of 140 consecutive patients without resting wall motion abnormalities were screened to undergo dobutamine stress MCE with power modulation and coronary angiography. Significant coronary disease was defined by the quantification of over 50% stenosis in a major epicardial vessel. The visual identification of wall motion and myocardial perfusion abnormalities was determined by blind review. RESULTS: Eight patients were excluded due to suboptimal images (feasibility 94.3%). Myocardial contrast enhancement analysis and wall motion analysis were similar in terms of sensitivity (81.2% versus 83.5%, respectively) and specificity (76.5% versus 80.9%, respectively) in detecting the presence of CAD. Myocardial contrast enhancement analysis tended to have a greater sensitivity than wall motion analysis in detecting the ischemic extent over multiple vascular territories among patients with multiple-vessel disease (sensitivity 83.8% versus 71.4% [P=0.09], and abnormal segment length 54.7+/-21.1% versus 48.9+/-24.7% [P=0.03] for myocardial contrast enhancement and wall motion analysis, respectively). There was good concordance between the presence of myocardial ischemia and wall motion abnormality for the segment-by-segment analysis (89.7% agreement, kappa = 0.745). The correlation of the wall motion score and perfusion score at peak stress was also good (r=0.793, P=0.015). CONCLUSIONS: Dobutamine stress MCE with power modulation is similar in sensitivity and specificity to wall motion analysis for detecting the presence of CAD. However, it provides greater sensitivity in evaluating the extent of ischemia in patients with multiple-vessel disease.  相似文献   

8.
This study examined the feasibility and potential clinical utility of magnetic resonance imaging (MRI) evaluation of myocardial perfusion (first-pass contrast enhancement) and viability (myocardial delayed enhancement) in 30 patients with congenital and acquired pediatric heart disease. Good agreement was found between MRI evaluation of myocardial perfusion and viability and analysis of segmental wall motion as well as coronary angiography (n = 10) and single photon emission computed tomography (n = 6).  相似文献   

9.
BACKGROUND: The clinical accuracy of myocardial contrast echocardiography (MCE) using intermittent harmonic imaging and intravenous perfluorocarbon containing microbubbles during dipyridamole stress has not been evaluated in a multicenter setting. HYPOTHESIS: The accuracy of dipyridamole stress contrast echo in the detection of coronary artery disease (CAD) using myocardial perfusion images is high in comparison with technetium-99 (99Tc) sestamibi single-photon emission computed tomography (MIBI SPECT) and increases the accuracy of wall motion data. METHODS: In 68 consecutive nonselected patients (46 men; mean age 66 years) from three different institutions in two countries. dipyridamole stress echo and SPECT with 99mTc MIBI were compared. Continuous intravenous (IV) infusion of perfluorocarbon exposed sonicated dextrose albumin (PESDA) (2-5 cc/min) was administered for baseline myocardial perfusion using triggered harmonic end systolic frames. Real-time digitized images were used for wall motion analysis. Dipyridamole was then injected in two steps: (1) 0.56 mg/kg for 3 min, (2) 0.28 mg/kg for 1 min, if the first step was negative for an inducible wall motion abnormality. After dipyridamole injection, myocardial contrast enhancement and wall motion were analyzed again by the same methodology. RESULTS: There were 35 patients with perfusion defects by SPECT. Wall motion was abnormal in 22, while MCE was abnormal in 32. Wall motion and MCE each had one false positive. The proportion of correctly assigned patients was significantly better with MCE than with wall motion (p = 0.03; chi square test). CONCLUSIONS: Myocardial contrast echocardiography, using intermittent harmonic imaging and intravenous perfluorocarbon containing microbubbles, is a very effective method for detecting coronary artery disease during dipyridamole stress echo.  相似文献   

10.
Myocardial contrast echocardiography (MCE) utilizes compressible microbubbles behaving similarly to red blood cells. Destruction of microbubbles and observation of the gradual refill into the myocardium are key to evaluating perfusion using real-time MCE. We aimed to assess the feasibility and diagnostic accuracy of qualitative MCE utilizing a 17-segment model for localization of myocardial perfusion abnormalities compared with simultaneous technetium-99 m sestamibi single-photon emission computed tomography (SPECT). From July 2005 through August 2007, 97 patients with known or suspected coronary artery disease underwent simultaneous SPECT and realtime MCE during adenosine stress. Qualitative MCE and tracer uptake were analyzed visually using a 17-segment model in a blinded manner. Diagnostic accuracy and 95% confidence interval (CI) were determined. Myocardial contrast echocardiography was completed in 91 patients (age, mean [SD], 69.3 [10.9] years; body mass index, 30.0 [6.3]; 59 males [65%]). Myocardial contrast echocardiography analysis was feasible in 88 (97%) patients (261 of 264 [99%] territories; 1299 of 1497 [87%] segments). At patient level, MCE sensitivity was 88% (95% CI, 79%–94%); specificity was 85% (77%–90%). For disease detection in individual coronary territories, sensitivity and specificity were 84% (71%–92%) and 79% (72%–84%) for the left anterior descending artery; 62% (38%–80%) and 88% (83%–91%) for the left circumflex artery; and 73% (57%–82%) and 94% (89%–97%) for the right coronary artery. For MCE combined with wall-motion analysis, concordance with SPECT improved from 80% to 86%. Myocardial contrast echocardiography interobserver concordance was 81% (κ [SE], 0.611 [0.78]). Myocardial contrast echocardiography accuracy was comparable in patients classified in accordance with presence of diabetes mellitus, myocardial infarction, hypertension, or percutaneous coronary intervention. Improved MCE specificity in detecting perfusion defects was seen in patients with no history of coronary bypass graft surgery (P = 0.005). Real-time MCE with a 17-segment model for analysis has good feasibility and accuracy in evaluation of myocardial perfusion during adenosine stress.  相似文献   

11.
In patients with chronic coronary artery disease different therapeutic strategies, such as optimal medical therapy, revascularization by percutaneous coronary intervention or coronary artery bypass grafting have been shown to improve the prognosis and symptoms and yield proven superiority over other treatment strategies in different patient populations. Thus, individual assessment of cardiac function and structure is of paramount importance to choose the optimal therapeutic strategy and subsequently improve patient prognosis. In this setting cardiac magnetic resonance imaging (CMR) has been shown to provide important diagnostic information. Myocardial ischemia can be detected by either perfusion stress CMR demonstrating perfusion deficits indicative of hemodynamically relevant coronary artery stenosis or dobutamin stress CMR for objectifying wall motion abnormalities during stress. Both techniques are superior to single photon emission computerized tomography and stress echocardiography in specific patient populations. Myocardial viability can be assessed by means of end-diastolic wall thickness or delayed enhancement imaging which allows quantification of the transmural extent of scarring. Furthermore, low-dose dobutamin stress CMR can detect a contractile reserve. Delayed enhancement imaging leads to accurate results due to its high resolution, can be performed at rest requiring no stress within a short time period and is easy to analyze. Thus this technique can be recommended as the favored technique to assess myocardial viability. In the following article the CMR techniques for ischemia and viability testing will be presented and their role in diagnosis and therapy of chronic myocardial ischemia will be discussed.  相似文献   

12.
In a pilot study of 27 patients, those who presented with chest pain underwent 2 dobutamine stress echocardiographic studies, 1 with high mechanical index harmonic imaging to analyze wall motion without contrast and 1 with real-time low mechanical index perfusion imaging with intravenous Optison to assess myocardial perfusion and wall motion. All patients then underwent quantitative coronary angiography. Two independent reviewers demonstrated an improvement in sensitivity when analyzing myocardial perfusion. In the 21 patients who had significant coronary stenoses, 14 had abnormal myocardial perfusion detected at peak stress and 7 had abnormal wall motion detected by standard dobutamine stress echocardiography. There was decreased specificity with perfusion imaging by 1 reviewer. The addition of real-time perfusion imaging after intravenous contrast during dobutamine stress echocardiography has the potential to improve detection of coronary artery disease.  相似文献   

13.
冠状动脉粥样硬化性心脏病是许多国家首要的死亡原因,正电子发射断层扫描可以清晰地显示心肌灌注,室壁运动和心肌活性,成为诊断冠状动脉粥样硬化性心脏病的重要手段。而正电子发射断层扫描和多层螺旋X线断层扫描仪的融合,把钙化积分和无创性的X线断层扫描仪血管造影加入心肌灌注显像和代谢显像,为冠状动脉粥样硬化性心脏病的诊断提供形态和功能方面的信息。  相似文献   

14.
BackgroundAlthough dobutamine stress myocardial contrast echocardiography (DSMCE) has been widely used for the prediction of myocardial functional recovery, dynamic changes that occur at the microcirculatory level during stress have been studied limitedly. The objective of the present study was to use low-dose DSMCE to assess microvascular damage and predict myocardial functional recovery in coronary artery disease (CAD) patients receiving coronary artery bypass grafting.MethodsForty-six CAD patients were subjected to low-dose DSMCE, as well as echocardiography and coronary computed tomography angiography before revascularization, 1 year after coronary artery bypass grafting. Dynamic changes occurring at the microcirculatory level during stress were analyzed for the ability to predict functional recovery. Quantitative assessment of functional recovery was determined using myocardial blood flow (MBF) via receiver operating characteristic curve analyses.ResultsPatients who failed to recover had fewer changes in MBF (∆MBF) at rest and with stress compared with the segments showing functional recovery. Semiquantitative changes (enhanced or reduced) of the myocardial perfusion score (∆MPS) and quantitative changes in ∆MBF of stress myocardial contrast echocardiography enhanced the specificity of resting MPS and the sensitivity of wall motion scores (P < 0.05) for the prediction of functional recovery.ConclusionsSpecific stress ∆MBF more accurately reflected the extent of microvascular damage compared with wall motion scores and resting MPS. ∆MBF and ∆MPS under stress myocardial contrast echocardiography provided higher accuracy than wall motion scores and resting MPS in predicting functional recovery in CAD patients after revascularization.  相似文献   

15.
Myocardial contrast echocardiography has the potential to accurately detect functionally significant coronary artery disease during pharmacologic stress testing. Different low-mechanical index modalities, including triggering replenishment imaging (TRI) and real-time imaging (RTI), are currently used to identify myocardial perfusion defects. We compared the ability of TRI with that of RTI for detecting and localizing perfusion abnormalities. Thirty-six patients (62 +/- 14 years old, 15 men) underwent single-photon emission computed tomography (SPECT) with technetium-99m sestamibi and myocardial contrast echocardiography at baseline and after infusion of 0.56 mg/kg of dipyridamole. Sixteen of these patients also underwent quantitative angiography. Contrast-enhanced images were obtained in 4-, 3-, and 2-chamber views after intravenous bolus injections of lipid-encapsulated microbubbles (0.1 ml of Definity). A myocardial perfusion defect was defined by myocardial contrast echocardiography as a delay of >2 seconds in contrast replenishment after high-mechanical index flash impulse. The myocardial segments were divided into 3 major coronary territories. There was agreement in detecting perfusion defects between SPECT and TRI in 26 patients (72%, kappa = 0.46) and between SPECT and RTI in 27 patients (75%, kappa = 0.50). Agreements between myocardial contrast echocardiography and SPECT for localizing coronary territories with perfusion defects were 81% for TRI (kappa = 0.43) and 85% for RTI (kappa = 0.61). Accuracy of RTI for detecting >50% diameter stenoses by quantitative angiography was 79%, that of TRI was 71%, and that of SPECT was 65%. These data indicate that the different low-mechanical index imaging schemes are equivalent to radionuclide SPECT in accurately detecting diseased coronary artery territories during vasodilator stress.  相似文献   

16.
目的 :分析冠状动脉造影正常的心肌梗塞患者核素心肌灌注显像表现。  方法 :回顾总结了 18例冠状动脉造影正常的心肌梗塞患者 99m锝 -甲氧基异丁基异腈 (99m Tc- MIBI)静息心肌断层显像。  结果 :18例心肌梗塞患者心肌灌注显像均显示异常 ,12例有节段性缺损 ,6例未见缺损但可见心肌节段性稀疏。心肌灌注显像对心肌梗塞的定位与心电图 Q波比较 ,显示病变部位更明确。  结论 :心肌灌注显像提供了冠状动脉造影正常的心肌梗塞患者心肌损伤部位及程度。  相似文献   

17.
OBJECTIVES: We sought to determine the feasibility and accuracy of real-time imaging of myocardial contrast echocardiography (MCE) in detecting myocardial perfusion defects during exercise echocardiography compared with radionuclide tomography. BACKGROUND: Ultrasound imaging at a low mechanical index and frame rate (10 to 20 Hz) after intravenous injections of perfluorocarbon containing microbubbles has the potential to evaluate myocardial perfusion and wall motion (WVM) simultaneously and in real time. METHODS: One hundred consecutive patients with intermediate-to-high probability of coronary artery disease underwent treadmill (n = 50) or supine bicycle (n = 50) exercise echocardiography. Segmental perfusion with MCE and WM w ere assessed in real time before and at peak exercise using low mechanical index (0.3) and frame rates of 10 to 20 Hz after 0.3 ml bolus injections of intravenous Optison (Mallinckrodt Inc., San Diego, California). All patients had a dual isotope (rest thallium-201, stress sestamibi) study performed during the same exercise session, and 44 patients had subsequent quantitative coronary angiography. RESULTS: In the 100 patients, agreement between MCE and single photon emission computed tomography (SPECT) was 76%, while it was 88% between MCE and WM assessment. Compared with quantitative angiography, sensitivity of MCE, SPECT and WM was comparable (75%), with a specificity ranging from 81% to 100%. The combination of MCE and WM had the best balance between sensitivity and specificity (86% and 88%,respectively) with the highest accuracy (86%). CONCLUSIONS: The real-time assessment of myocardial perfusion during exercise stress echocardiography can be achieved with imaging at low mechanical index and frame rates. The combination of WM and MCE correlates well with SPECT and is a promising important addition to conventional stress echocardiography.  相似文献   

18.
The intramyocardial coronary microvasculature has an important role in regulating regional myocardial perfusion. Pathologic alterations of microvascular function may be present in early stages of coronary artery disease, myocardial hypertrophy, cardiomyopathy or systemic diseases such as arterial hypertension and diabetes mellitus. Fast computed tomography permits noninvasive simultaneous quantitation of regional intramyocardial blood volume and myocardial perfusion using indicator dilution principles. Our data indicate that especially the blood volume-to-flow relationship is sensitive enough to characterize and quantitate the functional impact of different pathologies along the coronary tree on microvascular function. This could be demonstrated for 1) acute impairment of microvascular function following coronary microembolization, 2) endothelial dysfunction induced by chronic hypercholesterolemia, 3) chronic epicardial non-significant stenoses, 4) physiologic maturation of the normal microvasculature and 5) quantification of heterogeneity of microvascular function. These findings, the methodological background and the concept itself are presented in this article. Application of the blood volume-to-flow relationship is not limited to fast-CT but may be used in any cross sectional imaging technique, such as MRI or echocardiography, as long as intramyocardial blood volume and perfusion can be quantitated simultaneously. This new noninvasive approach to the quantification of intramyocardial microvascular function may prove a useful adjunct to those imaging techniques that are used to noninvasively quantitate epicardial stenoses or regional wall motion abnormalities.  相似文献   

19.
The present study attempted to detect the viability of myocardium by quantitative automatic 3-dimensional analysis of the improvement of regional wall motion using an magnetic resonance imaging (MRI) tagging method. Twenty-two subjects with ischemic heart disease who had abnormal wall motion on echocardiography at rest were enrolled. All patients underwent dobutamine stress echocardiography (DSE), coronary arteriography and left ventriculography. The results were compared with those of 7 normal volunteers. MRI studies were done with myocardial tagging using the spatial modulation of magnetization technique. Automatic tracing with an original program was performed, and wall motion was compared before and during dobutamine infusion. The evaluation of myocardial viability with MRI and echocardiography had similar results in 19 (86.4%) of the 22 patients; 20 were studied by positron emission tomography or thallium-201 single photon emission computed tomography for myocardial viability, or studied for improvement of wall motion following coronary intervention. The sensitivity of dobutamine stress MRI (DSMRI) with tagging was 75.9% whereas that of DSE was 65.5%. The specificity of DSMRI was 85.7% (6/7) and that of DSE was 100% (7/7). The accuracy of DSMRI was 77.8% (28/36) and that of DSE 72.2% (26/36). DSMRI was shown to be superior to DSE in terms of evaluation of myocardial viability.  相似文献   

20.
A 56-year-old man with old anteroseptal myocardial infarction was admitted to treat a gradually expanding coronary aneurysm. Coronary angiography demonstrated the aneurysm and delayed flow in the left coronary descending artery. The aneurysm was successfully treated with stenting. Technetium-99m-sestamibi single photon emission computed tomography (SPECT) showed a persistent defect in the anterior infarcted area after stenting. Myocardial contrast echocardiography was performed using SystemFIVE and EchoPAC. Levovist was injected (1 ml, 1.5 ml/sec; bolus + 1 ml/sec; continuous infusion) by Pulsar. Myocardial reperfusion was observed by B-mode and anatomical M-mode before and after intervention. Time-intensity curves from the region of interest positioned within the interventricular septum showed the mean value at plateau increased from 10.8 to 25.1 dB. The persistent defect area demonstrated by SPECT was enhanced by myocardial contrast echocardiography after intervention. Myocardial contrast echocardiography is useful for the assessment of outcome after intervention and evaluation of improved coronary blood flow.  相似文献   

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