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1.
We hypothesized that myocardial contrast echocardiography (MCE) could be used to stratify risk in patients with suspected acute coronary syndrome but a nondiagnostic electrocardiogram and negative troponin. Pretest Thrombolysis In Myocardial Infarction (TIMI) scores were determined. Exercise electrocardiographic data in those patients undergoing treadmill stress echocardiography as part of risk evaluation were analyzed independently of echocardiographic data. On a separate day, low-power MCE at rest and during vasodilator stress was performed. All patients were followed for cardiac events (cardiac death, myocardial infarction, and revascularization). Of 148 patients, 27 demonstrated abnormal myocardial contrast echocardiographic results and had higher cardiac event rates compared with those with normal myocardial contrast echocardiographic findings (59% vs 7%, p <0.0001) at follow-up (8 +/- 5 months). Hard cardiac event rates (death and nonfatal myocardial infarction) were low (3%) in patients with normal myocardial contrast echocardiographic findings. Cardiac events in patients with abnormal myocardial contrast echocardiographic findings (59%) were significantly higher than those predicted by a high-risk TIMI score (33%, p = 0.0023) and compared with those predicted by high-risk exercise electrocardiography (80% vs 57%, p = 0.0003). In conclusion, stress MCE was superior to TIMI risk score and exercise electrocardiography in the assessment of risk in patients with suspected acute coronary syndrome, nondiagnostic electrocardiogram, and negative troponin.  相似文献   

2.
In patients who have acute coronary syndrome (ACS), rapid and accurate risk stratification is crucial. Real-time myocardial contrast echocardiography (MCE) extends the evaluation of wall motion abnormalities by assessing myocardial perfusion. We investigated whether MCE could contribute to clinical and biochemical markers in identifying patients who have ACS when presenting to the emergency department. Consecutive patients (n = 100) who presented with first occurrence of chest pain underwent MCE to evaluate myocardial perfusion. Contrast images were also analyzed quantitatively off-line by measuring peak signal intensity (A) and slope of signal intensity increase (beta) in 16 myocardial segments. Thirty-seven of 100 patients had ACS. MCE showed perfusion defects in 9 of 12 patients (75%) who had unstable angina and had high-grade stenotic lesions on an angiogram that were missed by assessment of troponin T. MCE identified all 6 patients who had non-ST-elevation myocardial infarction and no initial increase in troponin T and 17 of 19 patients who had non-ST-elevation myocardial infarction and an initial increase in troponin T. In 2 patients who had chest pain and increased troponin T, MCE excluded ACS by identifying perimyocarditis as the underlying cause. Multivariate logistic regression analysis showed that MCE was the strongest predictor of ACS, thus adding significant diagnostic value to conventional tests. Initial perfusion defect size correlated strongly with increased troponin T at 96 hours (r = 0.73, p <0.001) and with ejection fraction at 4 weeks of follow-up (r = -0.79, p <0.001). Thus, our data suggest that MCE can accurately identify patients who have ACS.  相似文献   

3.
BACKGROUND: Microvasculature damage after myocardial infarction (MI), known as "no-reflow" phenomenon, may occur in some patients with acute MI in spite of invasive treatment and opened infarct-related coronary artery. There are several non-invasive and invasive methods used for the coronary flow assessment at the tissue level. AIM: To compare the value of intravenous contrast echocardiography (MCE) in detecting myocardial perfusion defects in patients with acute MI with (99m)Tc MIBI SPECT study. METHODS: Sixteen patients (11 males, 5 females, mean age 55.4+/-10.2 years) underwent primary coronary angioplasty or facilitated angioplasty (with reduced dose of a fibrinolytic drug and glycoprotein IIb/IIIa inhibitor) (PCI) for acute anterior MI. TIMI grade flow, TIMI Myocardial Perfusion Grade (TMPG), corrected TIMI frame count (cTFC), wall motion score index (WMSI) and segmental perfusion by myocardial contrast echocardiography (MCE) were estimated in real time before and immediately after PCI. MCE was repeated on the third day after PCI. All patients underwent (99m)Tc MIBI SPECT study (SPECT) while at rest on the third day after PCI. The area at risk was defined as the number of segments with no perfusion before angioplasty. Reflow was defined as an increase in contrast score in the same segments after angioplasty. RESULTS: Baseline MCE showed 95 segments with perfusion defects. Immediately after PCI, 77 segments were found with perfusion defect; in 10 patients improvement of myocardial perfusion was observed whereas in 6 patients perfusion defect remained unchanged. On the third day further improvement was observed in 8 patients. The number of segments with perfusion defect decreased to 53. SPECT detected perfusion defect in 54 segments. The agreement between MCE and SPECT for detecting perfusion abnormality was 98% (kappa 0.94). CONCLUSIONS: MCE is a safe technique for detecting myocardial perfusion in patients with acute MI. MCE proves that both primary and facilitated angioplasty improve myocardial perfusion in two thirds of patients with acute MI. Serial MCE allows identification of patients with both early and late improvement of myocardial perfusion. There is a very strong correlation between MCE and SPECT in the assessment of perfusion defects.  相似文献   

4.
AIMS: To investigate whether myocardial contrast echocardiography using Sonazoid could be used for the serial evaluation of the presence and extent of myocardial perfusion defects in patients with a first acute myocardial infarction treated with primary PTCA, and specifically, (1) to evaluate safety and efficacy of myocardial contrast echocardiography to detect TIMI flow grade 0--2, (2) to evaluate the success of reperfusion and (3) to predict left ventricular recovery after 4 weeks follow-up. METHODS AND RESULTS: Fifty-nine patients underwent serial myocardial contrast echocardiography, immediately before primary PTCA (MCE1), 1 h (MCE2) and 12--24 h after PTCA (MCE3). A perfusion defect was observed in 21 of 24 patients (88%) with anterior acute myocardial infarction. All but one had TIMI flow grade 0--2 prior to PTCA. Nine of 31 patients (29%) with inferior acute myocardial infarction showed a perfusion defect and all had TIMI flow grade 0-2 prior to PTCA. Restoration of TIMI flow grade 3 was achieved in 73% of the patients by primary PTCA. A reduction in size of the initial perfusion defect of at least one segment (16 segment model) or no defect vs persistent defect in patients with anterior acute myocardial infarction was associated with improved global left ventricular function at 4 weeks; mean global wall motion score index 1.29+/-0.21 vs 1.66+/-0.31 (P=0.009). Multiple regression analysis in patients with an anterior acute myocardial infarction revealed that the extent of the perfusion defect at MCE3 was a significant (P=0.0005) independent predictor for left ventricular recovery at 4 weeks follow-up. The only other independent predictor was TIMI flow grade 3 post PTCA (P=0.007). CONCLUSION: Intravenous myocardial contrast echocardiography immediately prior to primary PTCA seems safe and is capable of detecting the presence of a perfusion defect and its subsequent dynamic changes, particularly in patients with a first anterior acute myocardial infarction. A significant reduction in size of the initial perfusion defect using serial myocardial contrast echocardiography predicts functional recovery after 4 weeks and these findings underscore the potential diagnostic value of intravenous myocardial contrast echocardiography.  相似文献   

5.
OBJECTIVES: We aimed to compare the effects of upstream tirofiban versus downstream high-dose bolus (HDB) tirofiban and abciximab on tissue level perfusion and troponin I release in high-risk non-ST-segment elevation acute coronary syndrome (ACS) patients treated with percutaneous coronary intervention (PCI). BACKGROUND: Optimal timing and dosage of glycoprotein IIb/IIIa inhibitors for ACS remain to be explored. METHODS: We randomized 93 high-risk ACS patients undergoing PCI to receive upstream (in the coronary care unit) tirofiban, downstream (just prior to PCI) HDB tirofiban, and downstream abciximab. We evaluated the effects of the three drug regimens on tissue-level perfusion using the corrected Thrombolysis In Myocardial Infarction (TIMI) frame count, the TIMI myocardial perfusion grade (TMPG), and intracoronary myocardial contrast echocardiography (MCE) before and immediately after PCI and after cardiac troponin I (cTnI). RESULTS: The TMPG 0/1 perfusion was significantly less frequent with upstream tirofiban compared with HDB tirofiban and abciximab both before (28.1% vs. 66.7% vs. 71%, respectively; p = 0.0009) and after PCI (6.2% vs. 20% vs. 35.5%, respectively; p = 0.015). Upstream tirofiban was also associated with a significantly higher MCE score index (0.88 +/- 0.18 vs. 0.77 +/- 0.32 vs. 0.71 +/- 0.30, respectively; p < 0.05). Post-procedural cTnI elevation was significantly less frequent among patients in the upstream tirofiban group compared with the HDB tirofiban and abciximab groups (9.4% vs. 30% vs. 38.7%, respectively; p = 0.018). The cTnI levels after PCI were significantly lower with upstream tirofiban compared with HDB tirofiban (3.8 +/- 4.1 vs. 7.2 +/- 12; p = 0.015) and abciximab (3.8 +/- 4.1 vs. 9 +/- 13.8; p = 0.0002) CONCLUSIONS: Among high-risk non-ST-segment-elevation ACS patients treated with an early invasive strategy, upstream tirofiban is associated with improved tissue-level perfusion and attenuated myocardial damage.  相似文献   

6.
BACKGROUND: In patients with left bundle branch block (LBBB), conventional tests such as electrocardiography and myocardial scintigraphy poorly evaluate coronary artery disease. It has been reported that myocardial contrast echocardiography (MCE) is capable of identifying patients with a postinfarction contractile reserve and myocardial functional recovery, also allowing the early identification of late left ventricular remodeling. The purpose of this study was to evaluate, retrospectively, myocardial perfusion in selected patients with LBBB. METHODS: Thirty patients (mean age 56 +/- 8 years) with LBBB, 15 with normal coronary arteries at angiography and 15 with a previous myocardial infarction and a critical one-vessel residual stenosis at angiography, underwent MCE from June 2000 to May 2001. MCE results were compared with rest thallium-201 myocardial scintigraphy. RESULTS: Among 15 LBBB patients with normal coronary arteries, MCE demonstrated normal perfusion in 14 patients, whereas 1 subject showed an impairment of septal perfusion. In the same group, rest thallium-201 myocardial scintigraphy showed an impaired septal perfusion in 14 patients, whereas 1 subject had a normal perfusion (MCE specificity 93% vs myocardial scintigraphy specificity 7%). Among 15 LBBB patients with coronary artery disease, MCE correctly identified a contrast defect in 14/15 patients, whereas rest thallium-201 myocardial scintigraphy demonstrated a perfusion defect in 15/15 patients (MCE sensitivity 93% vs scintigraphy sensitivity 100%). The two techniques showed a good agreement as for myocardial perfusion in the anterior wall (86.6% anterobasal; 86.6% mid-anterior; 80% distal anterior), the inferior wall (86.6%), the distal segment of the posterior lateral wall (83.3%), but a low concordance was found as for the basal septum (16.6%) and middistal septum (33.3%). CONCLUSIONS: MCE allows a diagnostic benefit in the detection of microvascular damage in patients with LBBB and unknown coronary artery disease, also in the presence of discordance with rest thallium-201 myocardial scintigraphy.  相似文献   

7.
Myocardial contrast echocardiography (MCE) visualizes myocardial perfusion abnormalities after acute myocardial infarction. However, the limited view of 2-dimensional echocardiography reduces its ability to estimate perfusion abnormalities, especially in the subendocardial region. Three-dimensional echocardiography provides images of the left ventricular endocardium directly. This study was conducted to evaluate the ability of 3-dimensional MCE to assess abnormalities of subendocardial perfusion. Intracoronary 2- and 3-dimensional MCE was performed after primary percutaneous coronary intervention in 47 patients with acute myocardial infarction. Myocardial perfusion within the risk area was evaluated as good, poor, or no reflow on 2-dimensional MCE or as good, poor, or no myocardial opacification in endocardium on 3-dimensional MCE. The 2 methods showed different distributions of perfusion patterns: good, poor, and no reflow on 2-dimensional MCE in 31 (66%), 9 (19%), and 7 (15%) patients and good, poor, and no myocardial opacification in endocardium on 3-dimensional MCE in 17 (36%), 16 (34%), and 14 (20%) patients, respectively. Although only 19 patients (61%) with good reflow on 2-dimensional MCE showed myocardial perfusion grade 3 on angiography, 16 of 17 patients (94%) with good myocardial opacification in endocardium on 3-dimensional MCE showed myocardial perfusion grade 3. Although there were no significant differences in peak creatine kinase among the 3 subsets classified by 2-dimensional MCE, peak creatine kinase showed significant differences not only among the 3 groups but also among the subsets classified by 3-dimensional MCE. Classification by 3-dimensional MCE also predicted regional wall motion after 4.6 +/- 2.7 months, with significant differences between each pair of groups, whereas there was significant overlap of these values between the group with poor reflow and other 2 groups by 2-dimensional MCE. In conclusion, 3-dimensional MCE is a feasible way to assess subendocardial perfusion and predicts infarct size and functional recovery more precisely than 2-dimensional MCE.  相似文献   

8.
Adequate collateral blood flow at rest can sustain myocardial viability despite persistent occlusion of the infarct-related artery (IRA) in acute myocardial infarction (AMI). This has therapeutic and prognostic implications. Studies addressing the value of intravenous myocardial contrast echocardiography (MCE) to detect collateral blood flow after AMI in humans are limited. Accordingly, 70 consecutive patients with AMI underwent low-power intravenous MCE using a Sonovue infusion 7 to 10 days after thrombolysis. Myocardial perfusion detected by MCE was analyzed (qualitatively and quantitatively) in the akinetic segments in 20 patients (29%) with an occluded IRA who subsequently underwent revascularization. Contractile reserve, which is a marker of myocardial viability, was assessed with low-dose dobutamine 12 weeks after mechanical revascularization. Of the 102 akinetic segments (32%), 37 (36%) showed contractile reserve. Contractile reserve was present in 24 of the 29 segments (83%) with homogenous contrast opacification and absent in 60 of the 73 segments (82%) with reduced/absent opacification. Quantitative peak contrast intensity, microbubble velocity, and myocardial blood flow were significantly higher (p <0.0001) in the segments with contractile reserve than in those without contractile reserve. Multiple logistic regression analysis using electrocardiographic, biochemical, and myocardial contrast echocardiographic markers of collateral blood flow showed that MCE (odds ratio 26.0, 95% confidence interval 6.3 to 108.0, p <0.001) was the only independent predictor of collateral blood flow as demonstrated by the presence of contractile reserve. MCE may thus be used as a reliable bedside technique for the accurate evaluation of collateral blood flow in the presence of an occluded IRA after AMI.  相似文献   

9.
We investigated whether myocardial contrast echocardiography (MCE) performed soon after acute myocardial infarction (AMI) improves risk stratification for late mortality. MCE after AMI identifies microvascular "no-reflow" and predicts early outcomes; however, the predictive value of MCE for late mortality is unknown. One hundred sixty-seven patients with anterior AMI and left ventricular dysfunction underwent MCE 2 days after admission, and a perfusion score index (PSI) was calculated. Long-term follow-up (mean 39 months) was available for all patients. Patients with normal and abnormal perfusion had similar baseline characteristics. Myocardial contrast echocardiographic PSI was a predictor of mortality as a continuous variable (odds ratio 3.2 for each 1.0 increase in PSI, 95% confidence interval 1.1 to 9.7, p = 0.04). In a logistic regression model, age (odds ratio 2.6 per decade, 95% confidence interval 1.6 to 4.4, p = 0.0002) and PSI (odds ratio 4.5 for each 1.0 increase in PSI, 95% confidence interval 1.3 to 15.4, p = 0.02) were the only significant predictors of mortality. In a subanalysis comparing patients >70 years old with abnormal PSI with all other patients, Kaplan-Meier estimates showed a marked difference in survival over a mean follow-up of 39 months (24% vs 4% mortality, p = 0.0002). In conclusion, MCE refines risk stratification soon after anterior AMI in patients with left ventricular dysfunction. Patients at very high and very low risk of mortality can be identified, and myocardial contrast echocardiographic data are incrementally useful compared with existing clinical and angiographic variables.  相似文献   

10.
OBJECTIVES: This study sought to determine whether residual myocardial viability determined by myocardial contrast echocardiography (MCE) after acute myocardial infarction (AMI) can predict hard cardiac events. BACKGROUND: Myocardial viability detected by MCE has been shown to predict recovery of left ventricular (LV) function in patients with AMI. However, to date no study has shown its value in predicting major adverse outcomes in AMI patients after thrombolysis. METHODS: Accordingly, 99 stable patients underwent low-power MCE at 7 +/- 2 days after AMI. Contrast defect index (CDI) was obtained by adding contrast scores (1 = homogenous; 2 = reduced; 3 = minimal/absent opacification) in all 16 LV segments divided by 16. At discharge, 65 (68%) patients had either undergone or were scheduled for revascularization independent of the MCE result. The patients were subsequently followed up for cardiac death and nonfatal AMI. RESULTS: Of the 99 patients, 95 were available for follow-up. Of these, 86 (87%) underwent thrombolysis. During the follow-up time of 46 +/- 16 months, there were 15 (16%) events (8 cardiac deaths and 7 nonfatal AMIs). Among the clinical, biochemical, electrocardiographic, echocardiographic, and coronary arteriographic markers of prognosis, the extent of residual myocardial viability was an independent predictor of cardiac death (p = 0.01) and cardiac death or AMI (p = 0.002). A CDI of < or = 1.86 and < or = 1.67 predicted survival and survival or absence of recurrent AMI in 99% and 95% of the patients, respectively. CONCLUSIONS: The extent of residual myocardial viability predicted by MCE is a powerful independent predictor of hard cardiac events in patients after AMI.  相似文献   

11.
The management of patients infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be difficult due to the need for dedicated in-hospital pathways, protective measures for healthcare professionals and isolated beds of intensive care, particularly in areas overwhelmed by wide viral spread. Although pneumonia is the most common clinical manifestation in coronavirus disease 2019 (COVID-19), a variety of cardiovascular complications have been reported. An integrated diagnostic algorithm in SARS-CoV-2-infected patients with suspected cardiac involvement (laboratory findings of myocardial injury and electrocardiographic changes) may help to avoid unnecessary examinations and minimize the risk of operator infection. Due to its mobility and bedside feasibility, echocardiography is the first-line imaging technique in this clinical setting. It quickly provides information on ventricular functions, pulmonary hypertension, valve disease and pericardial effusion. In case of ST-segment elevation (STE), urgent coronary angiography should be performed. Cardiac ultrasound helps distinguish between ischemic and non-ischemic myocardial disease and may detect pericardial disease. Transmural ischemic electrocardiographic changes, with or without early elevated troponin levels or echocardiographic wall motion abnormalities, will determine the need for early invasive coronary angiography.Computed tomography (CT) through its multiple applications (chest CT; CT pulmonary angiography and coronary CT angiography; late iodine enhancement CT) and cardiac magnetic resonance might be helpful in reinforcing or redirecting diagnostic hypothesis emerged by other clinical, electrocardiographic and echocardiographic findings. The current pandemic makes it challenging to perform serial invasive and non-invasive diagnostic testing in COVID-19 patients and high serum troponin level. Nevertheless, thoughtful and systematic use of an appropriate multimodality imaging strategy is clinically relevant to detect cardiac injury and distinguish myocardial infarction from, myocarditis, takotsubo syndrome and pulmonary embolism.  相似文献   

12.
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。  相似文献   

13.
Background: Myocardial contrast stress echocardiography (stress MCE) is a novel method for diagnosing coronary artery disease (CAD). Few studies have compared the diagnosis of ischemia by stress MCE to angiographic CAD. Methods: Dobutamine stress MCE and SonoVue contrast infusion were performed before an elective percutaneous coronary intervention in 37 patients (8 women) aged 45–75 years with symptomatic CAD and at least one significant coronary artery stenosis measured by quantitative coronary angiography (QCA). The total and regional perfusion and wall motion (WM) were scored as normal or abnormal and attributed to the three main epicardial coronary arteries using a 17-segment left ventricular model. Results: An intermediate stress level was obtained in 29 (78%) patients, and 2 (5%) patients obtained peak stress. A perfusion defect was detected in 92% and WM abnormality in 57% of the patients at peak stress (P < 0.01). By perfusion, 70% of stenoses were both detected and correctly anatomically located, compared to 42% by WM (P < 0.01). All 21 patients with multivessel disease and/or proximal left anterior descending (LAD) stenosis measured by QCA were identified by stress-induced perfusion defects, while only 11 of them were identified by WM abnormalities (P < 0.01). Conclusion: Perfusion scoring is superior to WM scoring during stress MCE for diagnosing significant CAD in patients obtaining intermediate stress level, in particular, when multivessel disease or proximal LAD stenosis is present.  相似文献   

14.
目的利用经冠状动脉超声心肌声学造影(MCE)比较单支血管不同程度狭窄病变冠心病患者经皮冠状动脉介入术(PCI)后心肌灌注的变化,并探讨其临床意义。方法62例进行PCI治疗的住院患者根据选择性冠状动脉造影结果,按血管狭窄程度分组:A组,血管狭窄75%95%;B组,血管狭窄>95%;C组,急性血管闭塞。PCI前及术后15 min进行经冠状动脉MCE,检测心肌灌注状况。其中,MCE有关定量参数分别为:造影剂峰值密度反映心肌血容量;峰值时间反映心肌灌注速度;曲线下面积反映心肌血流量。结果所有患者PC I后均达到TIMIⅢ级血流;A组术后心肌血流量较术前增加(P<0.05);B组心肌血容量及血流量也较术前增加(P<0.05);而C组心肌血容量、血流量及灌注速度较术前增加更显著(P<0.01)。结论不同狭窄程度病变冠心病患者,PCI后心肌灌注均得到不同程度改善,其中,以急性闭塞病变改善最明显,该类患者为PCI治疗的最大获益者。  相似文献   

15.
Myocardial contrast echocardiography in acute coronary syndromes   总被引:8,自引:0,他引:8  
Myocardial contrast echocardiography (MCE) is an emerging technique in which microbubble contrast agents are visualized in the coronary microvasculature. MCE is an ideal modality for the noninvasive evaluation of acute coronary syndromes because it provides portable, simultaneous assessment of regional wall motion and myocardial perfusion. Recent advances in microbubble contrast agents and ultrasound imaging technology have allowed new clinical applications of MCE in acute coronary syndromes. Studies suggest a promising role for MCE in the evaluation of chest pain, the diagnosis and prognosis in acute myocardial infarction, the assessment of the success of reperfusion, and the differentiation of myocardial stunning from myocardial necrosis. Potential future applications of MCE in acute coronary syndromes include the detection of inflammation and ultrasound induced thrombolysis. The following serves as a review of the current status of myocardial contrast echocardiography in acute coronary syndromes.  相似文献   

16.
The aim of the study was to evaluate the accuracy of intermittent, harmonic power Doppler (HPD) during intravenous Levovist infusion in identifying myocardial perfusion abnormalities in patients with recent infarction. Fifty-five patients with first acute myocardial infarction, successfully treated by primary PTCA, were studied after 1 month by myocardial contrast echocardiography (MCE), 99mTc tetrofosmin single photon emission computed tomography (SPECT), and low dose dobutamine echocardiography (DE). Scoring myocardial perfusion as normal, moderately, or severely reduced; MCE and SPECT were in agreement in 71% of segments(k = 0.414). Discordance was mainly due to ventricular walls with normal enhancement by MCE and moderate perfusion abnormalities by SPECT. Scoring perfusion as present or absent, the agreement significantly improved up to 86% (k = 0.59). Sensitivity and specificity of HPD for identifying SPECT perfusion defects were 63% and 93%, respectively. The agreement between MCE and SPECT was higher(85%, k = 0.627)in patients with anterior infarction. An improvement in regional contractile function was noted after dobutamine in 79 dysfunctional segments. A normal perfusion or a moderate perfusion defect by MCE were detected in 71 of 79 of these segments, while a severe perfusion defect was observed in 59 of 85 ventricular segments without dobutamine-induced wall-motion improvement. Sensitivity and specificity by HPD in detecting segments with contractile reserve were 90% and 69%, respectively. Thus, intermittent HPD during Levovist infusion allows myocardial perfusion abnormalities to be detected in patients with recent infarction. This method has a limited sensitivity but a high specificity in detecting SPECT perfusion defects, and a good sensitivity but a limited specificity in detecting contractile reserve.  相似文献   

17.
Objectives. We sought to evaluate the comparative accuracy of myocardial contrast echocardiography (MCE), quantitative rest-redistribution thallium-201 (Tl-201) tomography and low and high dose (up to 40 μg/kg body weight per min) dobutamine echocardiography (DE) in identifying myocardial hibernation.Background. Myocardial contrast echocardiography can assess myocardial perfusion and may therefore be useful in predicting myocardial hibernation. However, its accuracy in comparison to myocardial perfusion scintigraphy and to that of high dose DE remains to be investigated.Methods. Eighteen patients (aged [±SD] 57 ± 10 years) with stable coronary artery disease and ventricular dysfunction underwent the above three modalities before coronary revascularization. Myocardial contrast echocardiography was achieved with intracoronary Albunex. Rest echocardiographic and Tl-201 studies were repeated ≥6 weeks after revascularization.Results. Of 109 revascularized segments with severe dysfunction, 46 (42%) improved. Left ventricular ejection fraction increased from 38 ± 14% to 45 ± 13% at follow-up (p = 0.003). Rest Tl-201 uptake and the ratio of peak contrast intensity of dysfunctional to normal segments with MCE were higher (p < 0.01) in segments that recovered function compared with those that did not. Myocardial contrast echocardiography, thallium scintigraphy and any contractile reserve during DE had a similar sensitivity (89% to 91%) with a lower specificity (43% to 66%) for recovery of function. A biphasic response during DE was the most specific (83%) and the least sensitive (68%) (p < 0.01). The best concordance with MCE was Tl-201 (80%, kappa 0.57). Changes in ejection fraction after revascularization related significantly to the number of viable dysfunctional segments by all modalities (r = 0.54 to 0.65).Conclusions. In myocardial hibernation, methods evaluating rest perfusion (MCE, Tl-201) or any contractile reserve have a similar high sensitivity but a low specificity for predicting recovery of function. A limited contractile reserve (biphasic response) increases the specificity of DE. Importantly, the three techniques identified all patients who had significant improvement in global ventricular function.(J Am Coll Cardiol 1997;29:985–93)© 1997 by the American College of Cardiology  相似文献   

18.
Microvascular integrity, as seen by myocardial contrast echocardiography (MCE), assesses whether myocardium has been successfully reperfused after an acute myocardial infarction. Until now this has been demonstrated only with intracoronary injection of an ultrasound contrast agent. Power Doppler imaging is a recently developed myocardial contrast echocardiographic method that counts the contrast microbubbles destroyed by ultrasounds and displays this number in color. This study sought to evaluate whether power Doppler MCE is able to visualize myocardial reperfusion during intravenous contrast injection. Thirty patients were evaluated 2 days after their first myocardial infarction during intravenous infusion of perfluorocarbon-exposed sonicated dextrose albumin (PESDA). Coronary artery angiography and single-photon emission computed tomography (SPECT) were used as reference techniques. A 16-segment left ventricular model was used to relate perfusion to coronary artery territories. Sensitivity and specificity of power Doppler MCE for segments supplied by infarct-related arteries were 82% and 95%, respectively. Accuracy of power Doppler MCE and SPECT were similar (90% vs 92% on segmental basis and 98% vs 98% on coronary artery territory basis). Two-dimensional echocardiography was repeated after 6 weeks. Segments recovering wall motion after 6 weeks were defined as stunning myocardium. Dysfunctional but perfused myocardium at day 2 after the infarction showed a better late recovery of wall motion compared with dysfunctional but nonperfused myocardium (p <0.001). In conclusion, harmonic power Doppler imaging is a sensitive and specific method for the identification of myocardial reperfusion early after myocardial infarction. It yields prognostic information for late recovery of ventricular function differentiating stunning (dysfunctional but perfused) from necrotic myocardium (dysfunctional and nonperfused).  相似文献   

19.
This study evaluated recently suggested invasive and noninvasive parameters of myocardial reperfusion after acute myocardial infarction (AMI), assessing their predictive value for left ventricular function 4 weeks after AMI and reperfusion defined by myocardial contrast echocardiography (MCE). In 38 patients, angiographic myocardial blush grade, corrected Thrombolysis In Myocardial Infarction frame count, ST-segment elevation index, and coronary flow reserve (n = 25) were determined immediately after primary percutaneous transluminal coronary angioplasty (PTCA) for first AMI, and intravenous MCE was determined before, and at 1 and 24 hours after PTCA to evaluate myocardial reperfusion. Results were related to global wall motion index (GWMI) at 4 weeks. MCE 1 hour after PTCA showed good correlation with GWMI at 4 weeks (r = 0.684, p <0.001) and was in an analysis of variance the best parameter to predict GWMI 4 weeks after AMI. The ST-segment elevation index was close in its predictive value. Considering only invasive parameters of reperfusion myocardial blush grade was the best predictor of GWMI at 4 weeks (R2 = 0.3107, p <0.001). A MCE perfusion defect size at 24 hours of ≥50% of the MCE perfusion defect size before PTCA was used to define myocardial nonreperfusion. In a multivariate analysis, low myocardial blush grade class was the best predictor of nonreperfusion defined by MCE. Thus, intravenous MCE allows better prediction of left ventricular function 4 weeks after AMI than other evaluated parameters of myocardial reperfusion. Myocardial blush grade is the best predictor of nonreperfusion defined by MCE and is the invasive parameter with the greatest predictive value for left ventricular function after AMI. Coronary flow parameters are less predictive.  相似文献   

20.
The relative merits of myocardial contrast echocardiography (MCE) and magnetic resonance imaging (MRI) to predict myocardial function improvement after percutaneous coronary intervention have not been evaluated until now. We studied 35 consecutive patients with acute myocardial infarction who underwent percutaneous coronary intervention using MCE and MRI and first-pass imaging for evaluation of myocardial perfusion. Delayed-enhanced MRI was included as another method to differentiate viable from infarcted tissue. MCE was performed by power modulation and intravenous Sonovue. A 16-segment model of the left ventricle was used to analyze all myocardial contrast echocardiograms and magnetic resonance images. At 60 days of follow-up, MCE showed improvement of function in 115 of 192 (60%) dysfunctional segments. The sensitivity, specificity, and accuracy for the prediction of functional improvement were comparable among MCE (87%, 90%, and 88%), first-pass MRI (87%, 60%, and 79%), and delayed-enhancement MRI (75%, 100%, and 82%, respectively, all p = NS). In conclusion, MCE and MRI allowed for prediction of myocardial function improvement after percutaneous coronary intervention. MCE had a comparable accuracy and, as a bedside technique, may be an alternative tool in the acute phase of acute myocardial infarction.  相似文献   

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