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1.
目的探讨全心尖切面心肌背向散射积分参数评价心肌缺血的可靠性。方法分析22例冠心病(CAD)患者和18例冠状动脉定量造影(QCA)正常患者的全心尖切面心肌所测左室16个节段背向散射积分参数,分别比较cAD组中室壁运动异常节段心肌、室壁运动正常节段心肌及对照组心肌的CVIB、CVIB%及AII%值。结果CAD组中室壁运动异常节段心肌CVIB、CVIB%值均显著低于后二者,而AII%值则显著高于后二者。结论全心尖切面所测左室16个节段背向散射积分参数能够敏感、客观并比较全面地反映心肌缺血情况。  相似文献   

2.
Cardiomyocyte hypertrophy and interstitial fibrin deposition develop in cardiac allografts and contribute to the functional changes of transplanted hearts. We hypothesized that integrated backscatter (IBS) can detect these myocardial changes. A total of 32 heart transplant recipients with either no or mild acute rejection (International Society of Heart and Lung Transplantation grade IA) were enrolled in this study. IBS data of myocardium were collected immediately before simultaneous dobutamine stress echocardiography (DSE) and (201)thallium imaging. Coronary angiography and endomyocardial biopsy were also performed. Coronary angiography showed diffuse narrowing in 1 patient who also had abnormal results of IBS, DSE, and thallium results. In the other 31 patients with patent coronary arteries, there were 3 patients (10%) with abnormal DSE results, 19 patients (61%) with abnormal IBS patterns, and 16 patients (52%) with reversible thallium perfusion defects. Of the patients, 44% had cardiomyocyte hypertrophy and 56% interstitial fibrin deposition. There were significant differences in the prevalence of (201)thallium perfusion defects and serum cyclosporine levels between patients with and without abnormal IBS patterns. Pathologic changes were also associated with abnormal IBS patterns (p = 0.01). However, there was no association between abnormal IBS and DSE results. By multiple logistic regression analysis, the abnormal IBS patterns were associated inversely with serum cyclosporine level (p = 0.028). In conclusion, abnormal IBS patterns are associated significantly with perfusion heterogeneity and pathologic changes in heart transplant recipients without evident acute myocardial rejection. There is no association between abnormal IBS patterns and dobutamine-induced dyssynergy in these patients. IBS provides a noninvasive approach for detection of myocardial changes in transplanted hearts without evident acute rejection.  相似文献   

3.
Immediate poststress thallium-201 reinjection followed by imaging one hour later has been proposed as an alternative reinjection protocol. This procedure is patient-convenient and time-saving as it shortens the investigation time to maximally 2.5 hours. The efficacy of the immediate thallium-201 reinjection protocol was assessed in 305 patients with stress perfusion defects in whom we compared the scintigraphic findings of 210 consecutive patients who underwent the standard thallium-201 stress/redistribution/reinjection protocol (Group I), with 95 consective patients who subsequently underwent the thallium-201 stress/immediate reinjection protocol (Group II). In all patients three-view planar images were visually and quantitatively analyzed. In Group I, defect reversibility was observed in 433 of 622 (70%) stress perfusion defects compared to 220 of 320 (69%) segments in Group II (p=NS). With respect to Q-wave related segments, defect reversibility was seen in 102 of 172 (59%) segments in Group I compared to 34 of 63 (54%) in Group II (p=NS). Based on defect reversibility, the diagnosis of myocardial ischemia was made in 184 of 210 (88%) patients Group I compared to 86 of 95 (91%) patients in Group II (p=NS). These findings indicate that immediate thallium-201 reinjection imaging provides at least similar data on defect reversibility as the standard thallium-201 stress/redistribution/reinjection approach. In practical terms, the stress/immediate reinjection approach seems advantageous as it reduces imaging time, enhances patient throughout and can be considered as one comprehensive imaging procedure.  相似文献   

4.
目的探讨全心尖切面心肌背向散射积分参数评价心肌缺血的可靠性.方法分析22例冠心病(CAD)患者和18例冠状动脉定量造影(QCA)正常患者的全心尖切面心肌所测左室16个节段背向散射积分参数,分别比较CAD组中室壁运动异常节段心肌、室壁运动正常节段心肌及对照组心肌的CVIB、CVIB%及AII%值.结果 CAD组中室壁运动异常节段心肌CVIB、CVIB%值均显著低于后二者,而AII%值则显著高于后二者.结论全心尖切面所测左室16个节段背向散射积分参数能够敏感、客观并比较全面地反映心肌缺血情况.  相似文献   

5.
目的研究冠状动脉旁路移植术(CABG)前后心肌背向散射(IBS)参数的变化,评价心肌背向散射组织定征技术(MUTC)在CABG中的应用价值。方法对32例冠状动脉左前降支病变并且行左前降支架桥术的病人,于术前、术后2~6周、3个月、半年分别行超声心动图检查。观测指标包括:M-mode定量左室前壁的运动幅度及室壁增厚率,显示AD状态下心肌的背向散射图像,分析缺血心肌和非缺血心肌,缺血心肌手术前后的背向散射积分(AⅡ)、周期性变化曲线的幅度(CVIB)和形态(IB曲线形态评分)的变化。结果术前缺血心肌较非缺血区心肌的IBS%值升高、CVIB值降低,IB曲线形态评分升高。术后室壁运动恢复节段与无室壁运动恢复节段相比,其术前的CVIB值高、IB曲线形态评分低,两者呈显著性差异。缺血心肌术后IBS%值降低、CVIB值增高,IB曲线形态评分降低,这种变化以术后3月最为明显。结论冠状动脉旁路移植术后心肌背向散射参数有明显改变,MUTC技术所测定的IBS参数能相对客观的预测、评价手术疗效。  相似文献   

6.
Acute myocardial ischemia and chronic myocardial infarction may be recognized with ultrasound tissue characterization techniques because of myocardial acoustic changes caused by reduced perfusion and/or collagen deposition. Our purpose was to study the acoustic properties of recent myocardial infarction when the predominating pathologic finding was myocardial edema and leukocytic infiltration. We used a new quantitative backscatter imaging system to study 18 patients 9 +/- 5 days after myocardial infarction (eight patients with anteroseptal myocardial infarction and 10 with inferior myocardial infarction) and 20 normal subjects. The cyclic variation of relative integrated backscatter (end-diastolic minus end-systolic) was calculated from on-line measurements. Standard parasternal long- and short-axis and apical four- and two-chamber views were obtained. In the anteroseptal myocardial infarction group, the cyclic variation of relative integrated backscatter was lower in the septum (1.5 +/- 1.6 dB) than in the posteroinferior wall (3.2 +/- 1.2 dB); however, the sample size of only three patients (of eight patients imaged) in the latter group prevented statistical comparison. The cyclic variation of relative integrated backscatter in the infarcted septum was less than the measurement obtained in the septum of the control group (4.3 +/- 2.4 dB, p less than 0.05). In the inferior infarction group, the cyclic variation of integrated backscatter in the posteroinferior wall (1.8 +/- 1.7 dB) was not significantly different from the measurement obtained in the septum (3.7 +/- 3.6 dB); however, the cyclic variation in the posteroinferior wall was significantly less than that obtained in the control group posteroinferior wall (5.7 +/- 1.7 dB, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
目的探讨心肌背向散射积分(IBS)参数评估心肌梗死患者心肌病变的价值及其与局部心肌收缩功能的关系。方法用背向散射联机分析技术,观测31例前间壁心肌梗死患者及27例正常人前间隔标化平均背向散射积分(AII%),背向散射积分周期变异幅度(CVIB);通过二维超声测算室壁增厚率(WT%)。结果与正常人相比,心肌梗死患者的AII%明显增加(2.2±0.3vs1.6±0.2,P<0.01),CVIB明显减低(3.3±1.7vs7.9±1.3,P<0.01)。CVIB与反映局部心肌收缩功能的指标(WT%)呈高度相关(r为0.78,P<0.01),AII%和WT%呈一定程度相关(r为-0.56,P<0.01)。结论IBS两个参数,即AII%和CVIB,可以区分正常心肌和梗死区心肌,并能反映局部心肌收缩功能,具有评估心肌存活性的潜力。  相似文献   

8.
潘生丁负荷超声心动图评价心肌缺血   总被引:1,自引:0,他引:1  
本文对19例患者行低剂量及大剂量潘生丁负荷超声心动图检查,并与冠脉造影结果比较。患者均为男性,平均年龄55±12岁。临床考虑冠心病,包括13例心梗患者,4例经PTCA治疗。结果发现6例负荷前后均无室壁运动异常,其中5例冠脉造影基本正常,1例有单支局部65%的狭窄;另有6例静息时即有室壁运动异常,负荷后无变化;1例PTCA治疗者负荷后室壁运动有改善;6例负荷试验阳性,其中5例低剂量阳性者冠脉造影示多支病变重度狭窄,另1例在大剂量时阳性,冠脉造影虽为三支病变但最大狭窄程度为75%。结论:潘生丁负荷试验简单实用,检测多支病变准确率高,还可帮助识别PTCA后血供的明显改善。低剂量阳性者提示多支病变、重度狭窄,可帮助筛选高危患者,判断预后  相似文献   

9.
目的探讨背向散射积分(IBS)技术在检测慢性肾功能衰竭发展过程中心肌病变的价值。方法 15只家兔每日注射阳离子化牛血清白蛋白(C-BSA)共8周,建立慢性肾功能衰竭模型。分别于注射C-BSA前、注射C-BSA后2周、4周、6周、8周对家兔心脏进行常规超声参数测量及背向散射积分参数测定,同时检测血肌酐、尿素氮;每次超声检查结束后,随机处死1只家兔,取肾脏和心脏行病理检查。结果 (1)注射C-BSA前心肌IBS呈周期性变化,舒张末期最大,收缩末期最小,曲线形态似正弦波;注射C-BSA后4周起各检测时间点室间隔和左心室后壁的标化IBS值(IBS%)持续增高,背向散射积分周期变化幅度(CVIB)持续降低(P0.05或P0.01);(2)常规超声心动图参数包括左心房室腔内径、室间隔厚度、左心室后壁厚度、射血分数、缩短分数以及E/A比值在注射C-BSA前、后各时间点之间差异均无统计学意义;(3)血肌酐、尿素氮自注射后6周起明显升高(P0.05或P0.01)。结论在慢性肾功能衰竭的发展过程中,心肌背向散射积分技术能够敏感地定量检测心肌的组织病理学变化。  相似文献   

10.
不同程度缺血心肌超声背向散射参数变化的实验研究   总被引:4,自引:0,他引:4  
目的:探讨不同程度缺血心肌背向散射特性变化的规律。方法:用杂种犬20条建立不同程度心肌缺血的动物模型,测定心肌超声背向散射参数。结果:不同程度心肌缺血时心肌背向散射积分及周期变化幅度和两者的跨壁梯度均有显著的差别。结论:心肌超声背向散射参数可以作为判断心肌缺血程度的重要指标。  相似文献   

11.
BACKGROUND: Primary aldosteronism (PA) is a disease associated with hypersecretion of aldosterone caused by an aldosterone-producing adrenal adenoma, bilateral adrenal hyperplasia, and, although rarely, by adrenal carcinoma. Arterial hypertension induces several cardiovascular alterations that yield a high cardiovascular risk. It has been shown that reduced myocardial perfusion at rest, assessed by thallium-201 myocardial scintigraphy, was greater in PA than in essential hypertension (EH). However, it is still unknown whether reduced myocardial perfusion at rest and/or regional function abnormalities are present during exercise-induced myocardial stress. PURPOSE: We addressed the impact of PA on myocardial ischemia and sought to identify signs of exercise-induced myocardial ischemia (assessed by MIBI-SPECT and echocardiography) in patients with PA compared to patients with EH. Patients with consistent signs of myocardial ischemia on all of the tests were studied by coronary arteriography. PATIENTS: We studied 72 patients with PA and an age/sex-matched group of 72 patients with EH enrolled in the cross-sectional Primary Aldosteronism and Heart Italian Multicenter Study (PAHIMS). METHODS: Regional function was detected from echocardiographic measurement of wall motion done at baseline and immediately after exercise. Myocardial perfusion was evaluated by SPECT imaging after injecting 99mTc-MIBI with the same-day protocol using the rest-stress sequence. RESULTS: Although the conditions of arterial pressure, duration of hypertension, and target organ damage were equivalent, the patients with PA had greater incidence of both reversible perfusion defects and abnormalities of regional function. Moreover, multiple regression analysis showed that the high plasma aldosterone level was highly predictive for SPECT ischemic score and wall motion index, suggesting that PA contributes to cardiovascular risk over and above that associated with ventricular hypertrophy. Exercise-induced myocardial ischemia in PA was not segmental but widely distributed suggesting that this phenomenon was not related to abnormal coronary perfusion. Accordingly, of the 38 patients with PA who underwent coronarography, there was no presence of significant coronary atherosclerotic lesions in 30 (78.9%) of the patients. CONCLUSIONS: The PAHIMS observed more exercise-induced moderate myocardial ischemic defects (co-detected by SPECT and echocardiograms and not segmental but widely allocated) in patients with PA than in patients with EH. This phenomenon occurred in a greater percentage of patients with PA without significant coronary lesions (78.95%, n = 38), which supports the possible presence of small-vessel intramyocardial disease.  相似文献   

12.
目的 应用心肌组织超声背向散射积分(IBS)技术研究扩张型心肌病患者的声学特性及临床意义。方法 采用HPSONOS 5500彩色多普勒超声诊断仪配备声学密度定量(AD)分析软件,对比检测20例扩张型心肌病患者和20例正常人胸骨旁长轴观室间隔基底段及后壁、乳头肌水平短轴观中段室间隔及后壁的背向散射信号,获得IBS平均值、IB最大值及CVIB(周期变异率)及曲线形态。其中病例组5例进行复检。结果 扩张型心肌病组各节段的IBS校正平均值、IBS校正最大值均显著高于正常组(P<0.05),CVIB值则低于正常组(P<0.05),曲线形态多数呈不规则类型。5例复检患者中2例随临床症状改善而心肌IBS值较前有所降低、CVIB值有所增高。结论 扩张型心肌病患者的心肌IBS值升高、CVIB值减低、曲线形态异常,提示该病患者心肌间质纤维化增多,心肌收缩力呈某种程度丧失。心肌IBS值与心肌收缩力相关联,经治疗心功能改善者心肌IBS值有所降低、CVIB值有所增高。提示此类患者心肌间质纤维化较轻。  相似文献   

13.
OBJECTIVE: Differentiation between normal and abnormal physical state of the myocardium, not possible with conventional echocardiography, so far could be done with integrated backscatter (IBS) as a research tool only. METHODS: This study investigates myocardial texture analysis with new commercially available real time IBS in 12 normal individuals and in 18 patients with severe left ventricular dysfunction due to coronary artery disease (CAD) in 8 and dilated cardiomyopathy (DCM) in 10 patients. Analysis of IBS amplitude and cyclic variation (dB) in the parasternal long and short axis view of the septum and the posterior wall were measured and corrected with IBS curve of the blood to get absolute values. RESULTS: Compared to normal individuals patients with left ventricular dysfunction had a reduced myocardial cyclic variation (P<0.0001), which correlated to regional systolic wall thickening (r=0.64, P=0.001) and global shortening fraction (r=0.62, P<0.01). Although systolic wall thickening in the posterior wall was lower in CAD patients (% thickening, 11.9+/-10 vs. 21.9+/-8, P=0.004), absolute cyclic variation was reduced in both, CAD and DCM patients in the same order of magnitude. However, the higher maximal IBS amplitude in the posterior wall observed in CAD when compared to DCM patients (13.2+/-4.4 vs. 9.2+/-2.4 dB; P=0.002) indicate fibrosis or scar. The dissociation between cyclic variation and systolic wall thickening could implicate hybernating myocardium. CONCLUSION: Real-time IBS has progressed from research to routine as a tool to obtain additional and valuable information to conventional echocardiography in daily practice.  相似文献   

14.
We conducted a study to delineate the alterations in the cyclic changes of myocardial ultrasonic integrated backscatter (IBS) in patients receiving angioplasty for chronic coronary artery disease. Ultrasonic tissue characterization (UTC) and dobutamine stress echocardiography were performed in 43 patients before and 24 h after angioplasty, as well as before the follow-up angiography 3 months later. For segments being normokinetic with ischemic burden, the blunted amplitude and increased nadir deviation of IBS cyclic modulation recovered soon after angioplasty. For dyssynergic segments with contractile reserve, the angioplasty rebuilt the amplitude before the wall motion recovered, but corrected the nadir deviation tardily. In both circumstances, the coronary restenosis abolished the initial restoration. Those nonviable segments persistently revealed large deviations and small weighted amplitudes irrelevant to coronary lesions. The progress of myocardial ischemia, the development of wall motion dyssynergy and, then, the loss of viability, show different patterns of alterations in UTC after alleviating coronary obstructions.  相似文献   

15.
目的:进一步探讨组织多普勒和组织定征技术临床应用的可行性。方法:12例超声发现节段性室壁运动失常患者分别进行多巴酚丁胺负荷超声心动图、超声组织多普勒、背向散射积分及核素扫描检查。结果:有收缩储备节段背向散射积分曲线形态评分较无收缩储备节段明显降低,背向散射积分周期变异幅度(CVIB)、T波顶点时心内膜运动速度(Vendo)、心肌中部心动周期中最大运动速度(TVC)、收缩期心肌运动速度峰值跨壁梯度(MVGm+)及放射性核素摄取率均较无收缩储备节段显著增高,有收缩储备节段背向散射积分平均值(AII)与无收缩储备节段的差别无显著性。心肌收缩期运动指标与CVIB正相关,与AII负相关。放射性核素摄取率与TVC、Vendo、MVGm+正相关,与AII负相关,与CVIB相关呈临界状态。结论:背向散射积分和组织多普勒指标在判断心肌缺血与存活的临床应用方面有很大潜力。  相似文献   

16.
目的 应用背向散射积分技术研究糖尿病患者的心肌超声组织特征 ,旨在探讨背向散射积分 (integrated backscatter,IBS)参数测定在评价糖尿病患者心肌病变方面的临床应用价值。方法 采用 HP Sonos5 5 0 0型超声诊断仪 ,该机配置声学密度定量 -背向散射积分 (AD- IBS)联机采样分析软件 ,检测了 17例无微血管并发症的 2型糖尿病患者 (I组 )和 17例有微血管并发症的糖尿病患者 (II组 )以及 16例正常人 (对照组 )心肌的心动周期时间平均背向散射积分 (IBS)、背向散射积分标化值 (IBS% )、背向散射积分周期变异幅度 (CVIB)、背向散射积分跨壁梯度 (TGIB)等超声背向散射积分参数 ,采样部位为胸骨旁左室长轴切面室间隔及左室后壁心肌的中间段。同时测定糖尿病患者的糖化血红蛋白 (Hb A1c)水平。运用 t检验进行 3组受检者心肌超声背向散射积分参数的显著性检验 ,对糖尿病患者的 TGIB与Hb A1c进行相关性分析 ,P<0 .0 5定义为有统计学意义。结果  (1)糖尿病 I组、II组室间隔及左室后壁心肌的 IBS%均明显高于对照组 ;(2 )糖尿病 I组、II组室间隔及左室后壁心肌的 CVIB均明显低于对照组 ;(3)糖尿病 I组、II组室间隔及左室后壁心肌的 TGIB均显著高于对照组 ;(4 )糖尿病 II组室间隔及左室后壁心肌的 IBS%均明显高于糖  相似文献   

17.
目的 本研究旨在应用背向散射参数测定方法研究慢性肾功能衰竭患者的心肌超声组织超声组织特征,探讨该方法在评价慢性肾功能衰竭患者心肌病变方面的价值。方法 采用HP Sonos-5500型超声诊断仪,应用该机配置的AD-IBS软件,对38例慢性肾功能衰竭患者和30例正常人进行了心肌背向工用射参数(IBS,CVIBS,CVIBS/IBS%)的测定,采样部位为胸骨旁左室长轴切面空间隔及左室后壁中段。结果 慢  相似文献   

18.
目的研究儿童扩张型心肌病心肌超声背向散射参数特点。方法采用超声背向散射积分技术,对20例扩张型心肌病(DCM)患儿及20例健康儿童,于左室长轴观采集室问隔中部及左室后壁心肌背向散射积分数据,包括校正平均背向散射积分(AⅡ%)和背向散射积分周期变化幅度(CVIB)。同时采集常规M型超声参数,并于心腔四腔观及五腔观,行脉冲多勒超声检查获得二尖瓣口和左室流出道血流图,计算左室Ri指数。结果与对照组比较,DCM组左室舒张末内径、收缩末内径、Tei指数、左室后壁AⅡ%增大(P〈0.01),室间隔、左室后壁CVIB减低(P〈0.01),背向散射积分曲线形态异常。DCM患儿心肌背向散射参数与左室Tei指数之间无相关性(P〉0.05)。结论扩张型心肌病儿童心肌背向散射参数变化特征:AⅡ%升高、CVIB下降、IBS曲线形态异常;左室Ri指数明显增高,心脏整体功能下降。  相似文献   

19.
BACKGROUND: A quantitative technique is required to reduce the subjectivity and improve the reproducibility of stress echocardiography. Tissue Doppler imaging may offer these benefits, but its feasibility with exercise echocardiography (ExE) is undefined. This study sought the determinants of the exercise tissue Doppler velocity (TDV) response and the feasibility and accuracy of color TDV during ExE. METHODS AND RESULTS: Fifteen volunteers and 85 patients (age 60 +/- 10 years, 19 women) with known or suspected coronary artery disease were studied with standard 2-dimensional (2D) echocardiography and pulsed wave (PW) and color TDV before and after they underwent exercise treadmill testing. After the study PW TDV was measured in 6 basal segments, and off-line software was used to display color TDV data from all myocardial segments. Color TDV was compared with PW TDV in the basal segments at rest and stress with the use of linear regression. Color TDV in mid and basal segments was compared with wall motion on 2D echocardiography. The predictors of the TDV response to exercise were defined in a multiple linear regression. A logistic regression model was used to integrate clinical, exercise, and TDV variables for prediction of abnormal regional left ventricular function. Color and PW correlated well at rest (r = 0.81) and stress (r = 0.84), but PW was greater than color velocities at rest and stress. On the basis of 2D echocardiography, 752 myocardial segments were classified as normal in patients without evidence of coronary disease, 309 were normal in patients with abnormal wall motion in another territory, and 128 showed ischemia or scar. Segmental comparison of velocities assessed by color TDV showed that scar segments had a lower velocity than normal segments at rest and stress (P <.001). Ischemic segments had a lower peak TDV and less increment in velocity than normal segments. Heart rate, functional capacity, and regional dysfunction (scar or ischemia) were independent predictors of TDV at peak exercise. With the use of receiver operating characteristic analysis, the "correction" of TDV by these other variables increased the accuracy of the technique for the detection of regional left ventricular dysfunction. CONCLUSION: Color TDV is feasible during ExE. The correlation found between TDV and wall motion analysis of experienced observers indicates that TDV may be useful as a quantitative tool for interpretation of ExE.  相似文献   

20.
We have previously shown that cardiac cycle-dependent variation of integrated backscatter occurs in normal myocardium. To determine whether myocardial ischemia and reperfusion can be distinguished by real-time integrated backscatter imaging we performed 10 min balloon occlusion of the Left Anterior Descending (LAD) coronary artery followed by reperfusion in 10 closed-chest anesthetized dogs. Images were obtained at baseline, during occlusion, and up to 120 min after reperfusion. We measured the magnitude and delay of cyclic variation of integrated backscatter in segments with and without asynergy. Radiolabeled microspheres were used to verify both ischemia and reperfusion. Ischemic segments exhibited decreased magnitude and increased normalized delay of cyclic variation of integrated backscatter (from 3.3 +/- 0.3 dB to 1.4 +/- 0.2 dB, mean +/- SE; and from 0.95 +/- 0.03 to 1.67 +/- 0.15, respectively, all p less than or equal to 0.001). Reperfusion promptly restored the magnitude of cyclic variation toward normal. However, the delay of the cyclic variation was restored only partially. Wall motion analysis of the ischemic sites revealed persistent abnormalities throughout the reperfusion interval despite return to normal of the magnitude and delay of cyclic variation. Thus, real-time integrated backscatter imaging permits detection and differentiation of changes in myocardial acoustic properties indicative of ischemia and of subsequent reperfusion.  相似文献   

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