声学密度定量评价老年肾功能不全的心肌改变

目的　探讨声学密度定量技术对老年慢性肾功能不全病人心肌改变的临床应用价值。方法　正常组 32例 ,慢性肾功能不全组 38例 ,分别进行超声背向散射积分 (IBS)、二次谐波 (SHI)和声学密度定量 (AD)检查。结果　 Loop方法显示 :正常组与异常组的左室前壁心肌声学密度曲线整体水平高于正常者 ;两种触发方式 IBS和 SHI曲线 :峰值和曲线下面积收缩期整体略高于舒张期 ,异常组均较正常组峰值和曲线下面积显著增高 (Ppd<0 .0 5,Pacu<0 .0 5)。结论　老年慢性肾功能不全病人心肌病理学改变的声学密度定量心肌超声组织定征是一种识别力高、相对无创、诊断有效而可靠的检测手段 ,降低了人为差异。     

声学密度技术在老年人肾小球疾病诊断中的应用价值

目的：探讨声学密度（AD）技术在老年人肾脏疾病检测中的临床应用价值。方法：测量44例肾小球疾病病人及20例正常人的肾皮质标化背向散射积分（IBS）值和肾髓质标化IBS值，结果：尿毒症患者皮质标化IBS值与髓质标化IBS值之间无显著差异（P＞0．05），而正常组、代偿期、氮质血症期患者上述两指标之间有显著差异（P＜0．05），尿毒症期患者和氮质血症期患者皮质标化IBS值均明显高于正常组（P＜0．05），尿毒症期患者髓质标化IBS明显高于正常组（P＜0．05），结论：应用AD技术检测老年肾脏能在一定程度上区分生理和病理下的差异对指导临床诊断有一定帮助。     

肥厚型心肌病与高血压性心脏病心肌超声组织定征的鉴别诊断

目的探讨肥厚型心肌病、高血压病患者与正常人左室后壁、室间隔心肌声学特性是否存在差异,以期将超声组织定征作为鉴别诊断的指标之一. 方法将被检者分成3组肥厚型心肌病组(HCM组)、高血压性心脏病组(EH组)及正常对照组,分别测定各组左室后壁、室间隔部位的心肌背向散射参数.结果左室后壁心肌HCM组与EH组的IBS、CVIB无显著性差异(P>0.05),而与正常对照组均有差异(P<0.05);室间隔部位3组IBS、CVIB均有显著性差异(P<0.05);HCM组室间隔、左室后壁均存在IBS、CVIB的跨壁梯度,而EH组、正常对照组则无上述异常存在.结论 HCM患者左室后壁心肌的声学特性与正常对照组有差异,室间隔与左室后壁均存在IBS、CVIB的跨壁梯度.因此背向散射参数测定可作为鉴别肥厚型心肌病和高血压性心脏病的一项指标.     

老年钙化性心脏瓣膜病的声学密度定量研究

目的 应用声学密度(AD)技术研究老年钙化性心脏瓣膜组织的超声特征,建立对该病定量诊断的方法.方法 采用HP-5500型彩色多普勒超声心动图仪,应用该机配置的背向散射积分采集、分析系统对21例老年性主动脉瓣钙化(AVC)患者、20例老年性二尖瓣钙化(MAC)患者和23例无瓣膜钙化正常体检者的瓣膜组织进行检测,获得其AD参数,同时获得相应各组的心包组织的AD参数,求得二者比值作为校正AD参数.结果 AVC和MAC组的校正图像平均强度(AII%)与对照组存在明显差异(均P＜0.001),瓣膜的AII%与瓣膜厚度呈正相关(P＜0.001).结论 AII%可成为鉴别正常瓣膜与钙化瓣膜并反映瓣膜钙化程度的定量指标.     

心肌声学密度定量分析检测高血压心肌纤维化

目的观察原发性高血压患者心肌声学密度和血清Ⅲ型前胶原末端肽(PⅢNP)含量的变化情况,以评估心肌声学密度定量分析技术检测高血压心肌纤维化的临床价值。方法入选原发性高血压患者75例(高血压组),另选健康体检者75例为对照组。应用超声心动图测量声学密度各项值,采用放免法测定PⅢNP的浓度。结果高血压组的声学强度(CAI)显著高于健康对照组(P<0·01),而高血压组的背向散射积分周期变化值(CVIB)(室间隔6·07±0·85,左室后壁7·00±1·15)显著低于健康对照组(室间隔8·60±3·12,左室后壁11·85±3·06,P<0·05);高血压组血清PⅢNP含量(109·9±7·5)μg/L显著高于健康对照组[(43·9±5·9)μg/L,P<0·01];血清PⅢNP与室间隔和左室后壁声学强度呈显著正相关(P<0·01),与室间隔和左室后壁CVIB呈显著负相关(P<0.01)。结论心肌声学密度定量分析技术是检测高血压心肌纤维化的一项可靠技术。     

卡维地洛对原发性高血压心肌组织特征及部分血管活性肽水平的改变

目的:应用超声声学密度技术探讨卡维地洛治疗原发性高血压患者左心室心肌组织密度的变化,分析治疗后部分血管活性肽心钠素、脑钠素、内皮素-1(ET-1)、降钙素基因相关肽(CGRP)、胰岛素样生长因子-1(IGF-1)水平的改变及其与心肌组织密度变化的关系。方法:将入选对象101例分为无左心室肥厚组56例及伴左心室肥厚组45例,应用超声声学密度技术测量治疗前后左心室心肌不同切面的平均声学密度(AII％);测量治疗前后部分血管活性肽心钠素、脑钠素、ET-1、CGRP、IGF-1水平,分析治疗前后其变化规律及与心肌声学密度变化的关系。结果:卡维地洛治疗后原发性高血压左心室各室壁AII％之和(SUM)较治疗前有显著性下降(P<0．05)。心钠素、脑钠素、IGF-1在无左心室肥厚组有下降的趋势(P>0．05),ET-1有显著性下降(P<0．05)。在伴左心室肥厚组心钠素、ET-1、IGF-1有显著性下降(P<0．05),脑钠素有下降趋势(P>0．05)。CGRP水平治疗后无左心室肥厚组有升高趋势(P>0．05),伴左心室肥厚组有显著性升高(P<0．05)。伴左心室肥厚组心肌各切面室壁SUM在治疗前后的变化ΔSUM与ΔET-1、Δ心钠素、ΔIGF-1等各因子水平呈正相关,与ΔCGRP水平呈负相关。结论:卡维地洛能降低原发性高血压左心室心肌组织密度;能使原发性高血压左心室肥厚两组心钠素、ET-1、CGRP、IGF-1等部分血管活性肽向有利于维持正常血压水平的方向改变。     

糖尿病患者左室超声背向散射改变的初步观察

目的　了解 2型糖尿病 (T2 DM)心肌背向散射 (IBS)变化的特点及其临床意义。　方法正常对照组 5 0例 ,T2 DM组 5 0例 ,病程≤ 5年 ,糖化血红蛋白 (Hb A1c) (9.6 9± 1.78) % ,应用HP5 5 0 0型超声诊断仪 ,在胸骨旁左室乳头肌短轴切面分别测量左心室前间壁、前壁、侧壁、后壁、下壁和后间隔心肌组织的 IBS,并将其与心包 IBS的比值作为心肌 IBS的校正值 (IB% ) ;舒张末期与收缩末期的差值即 CVIB,并将其与心包 IBS的比值作为心肌 CVIB的校正值 (CVIB% )。同时测定左室等容舒张期时间 (IVRT) ,二尖瓣血流图 E峰与 A峰的比值 (E/ A )。　结果　 T2 DM组心脏左室各室壁心肌背向散射参数与正常对照组比较 IB%增大 ,CVIB减低 ,差异非常显著 (P <0 .0 0 1) ,两组IVRT、E/ A均在正常范围 (P>0 .0 5 )。　结论　 T2 DM患者左室 IBS有明显的变化且呈弥漫性改变 ,左室 IBS的变化出现在舒张功能异常 (糖尿病心肌病亚临床期 )之前 ,背向散射技术可早期发现糖尿病心肌微结构的病变     

心肌声学密度定量分析检测高血压心肌纤维化

目的 观察原发性高血压患者心肌声学密度和血清Ⅲ型前胶原末端肽(PⅢNP)含量的变化情况,以评估心肌声学密度定量分析技术检测高血压心肌纤维化的临床价值.方法 入选原发性高血压患者75例(高血压组),另选健康体检者75例为对照组.应用超声心动图测量声学密度各项值,采用放免法测定PⅢNP的浓度.结果 高血压组的声学强度(CAI)显著高于健康对照组(P＜0.01),而高血压组的背向散射积分周期变化值(CVIB)(室间隔:6.07±0.85,左室后壁:7.00±1.15)显著低于健康对照组(室间隔:8.60±3.12,左室后壁:11.85±3.06,P＜0.05);高血压组血清PⅢNP含量(109.9±7.5)μg/L显著高于健康对照组[(43.9±5.9)μg/L,P＜0.01];血清PⅢNP与室间隔和左室后壁声学强度呈显著正相关(P＜0.01),与室间隔和左室后壁CVIB呈显著负相关(P＜0.01).结论 心肌声学密度定量分析技术是检测高血压心肌纤维化的一项可靠技术.     

用声学密度定量技术早期评价急性心肌梗死患者直接经皮冠状动脉腔内成形术的疗效

目的　探讨利用声学密度 (AD)定量技术早期评价急性心肌梗死 (AMI)患者行直接经皮冠状动脉腔内成形术 (PTCA)的手术疗效。方法　将 4 0例AMI患者分为两组 :18例病人行直接PTCA治疗 (A组 ) ,2 2例病人用药物治疗 (B组 ) ,比较两组病人在入院第 7天时常规超声心动图检查和用AD技术检测的结果。结果　两组病人常规超声心动图各项检查结果比较差别无显著性 (P >0 0 5 )。AD定量检测结果 :A组的背向散射积分周期变化幅度 (CVIB) (4 2± 1 3)dB明显高于B组 (2 5± 2 4 )dB(P <0 0 1) ;A组校正的周期变化延迟时间 (N Delay) 1 0 9± 0 0 8明显低于B组 1 31± 0 16 (P <0 0 1) ;两组间背向散射积分 (IBS)差异无显著性 (P >0 0 5 )。结论　AD技术能够早期反映AMI再灌注心肌的组织学特征 ,为早期评价介入治疗效果、预测心功能改善情况、判定心肌活性提供了一种新的技术手段。     

应用声学密度定量技术预测再灌注心肌存活

目的　评估声学密度定量 (AD)技术预测再灌注心肌存活的可能性。方法　对心肌梗死的病史六个月以内的 16例患者于PTCA术前及术后第 3天、半年进行 AD技术测定。仪器采用 HPSONOS- 5 5 0 0超声诊断仪。S4探头 ,频率 2～ 4MHz。将感兴趣区域置于梗死区 ,测量心肌的背向散射 (IBS)积分的心动周期变化幅度 (CVIB)和室壁增厚率。将测量所得参数进行配对 t检验 ,数据以 x± s表示 ,P<0 .0 5为有统计学意义。结果　 16例患者中 ,PTCA术后第 3天 ,CVIB较术前改变超过 1d B的有8例 ,(4 .1± 1.6 vs5 .5± 1.8d B,P<0 .0 5 ) ,CVIB…     

Myocardial ultrasonic tissue characterization for estimating histological abnormalities in hypertrophic cardiomyopathy: comparison with endomyocardial biopsy findings.

AIMS: In this study, we investigated the clinical usefulness of ultrasonic tissue characterization with integrated backscatter for the evaluation of myocardial histological abnormalities in comparison with endomyocardial biopsy findings in patients with hypertrophic cardiomyopathy. METHODS: Twenty patients with hypertrophic cardiomyopathy and 20 normal subjects were enrolled in this study. We measured two parameters for the ultrasonic tissue characterization with integrated backscatter: the magnitude of the cardiac-cycle-dependent variation in integrated backscatter signals (cdv-IB) and the mean value of integrated backscatter signals calibrated by the pericardium (cal-IB). These parameters were measured at both the interventricular septum and the left ventricular posterior wall. Histological findings of right ventricular endomyocardial biopsy specimens were analyzed by computer image analyzer. RESULTS: cdv-IB was significantly lower and cal-IB significantly higher in both the interventricular septum and the left ventricular posterior wall in patients with hypertrophic cardiomyopathy compared with normal subjects. In patients with hypertrophic cardiomyopathy, the degree of myocardial disarray, interstitial fibrosis, and nonhomogeneity of myocyte size showed positive correlations with cal-IB and negative correlations with cdv-IB. CONCLUSIONS: Ultrasonic tissue characterization with IB enables the noninvasive evaluation of myocardial histological abnormalities in patients with hypertrophic cardiomyopathy.     

背向散射技术与彩色室壁运动技术在高血压左室重构中的应用

目的 探讨背向散射和彩色室壁运动参数评估原发性高血压不同左室构型心肌病变程度和局部室壁运动的临床价值。方法 测定70例原发性高血压病患者和31例正常对照者室间隔及左室后壁的背向散射参数和局部室壁收缩期位移。共收入正常构型组18例，向心重构组17例，向心肥厚组23例，离心肥厚组12例。结果 高血压各组室间隔超声背向散射(IB％)均不同程度地增大，以向心性肥厚组和离心性肥厚组为著；左室后壁IB％在向心性肥厚组和离心性肥厚组增高，以离心性肥厚组为著；室间隔周期变化幅度(cvlB)在向心性肥厚组和离心性肥厚组减低；左室后壁的CVIB在离心性肥厚组显著减低；高血压各组均未出现明显的背向散射跨壁梯度的改变。室间隔和左室后壁的SEM在离心性肥厚组显著减低，其余各组间虽无明显统计学差异，但在向心性肥厚组呈现增加的趋势。在离心性肥厚组，收缩期CK色带变薄或消失，色带不完整。结论 心肌超声背向散射参数可用于判断高血压不同左室构型心肌病变的程度；彩色室壁运动技术可用于评估高血压不同左室构型局部室壁运动状态。     

Echocardiographic observation of acute myocarditis with systemic lupus erythematosus

Although myocarditis from a series of autopsies of patients with systemic lupus erythematosus was frequently observed, the incidence of clinically apparent myocardial dysfunction was low. A 30-year-old woman with systemic lupus erythematosus was examined by echocardiography. An acoustic densitometry was followed at the left ventricular posterior wall throughout the clinical course. A decrease in the magnitude of cyclic variation of integrated backscatter (IB) was observed before treatment. Following the combined treatment, steroid and cyclophosphamide, a repeated ultrasonic tissue characterization showed an increase in the magnitude of cyclic variation of IB. It is thought that ultrasonic tissue characterization may be a useful method to evaluate the impairment of contraction, and to follow up the clinical course of myocardial involvement in systemic lupus erythematosus.     

Integrated backscatter for the assessment of myocardial viability

PURPOSE OF REVIEW: Ultrasonic tissue characterization is a non-invasive diagnostic method that uses myocardial integrated backscatter analysis to determine contractile performance and myocardial viability independent of wall motion. This review discusses recent clinical findings regarding the application of ultrasonic tissue characterization for the assessment of myocardial viability. RECENT FINDINGS: As this technique is non-invasive, ultrasonic tissue characterization can be used to predict the patency of infarct-related arteries in patients in the early stage of acute myocardial infarction. Several recent studies have shown that this technique is useful in identifying myocardial contractile reserve. The accuracy of ultrasonic tissue characterization for predicting functional recovery after coronary reperfusion is comparable to dobutamine echocardiography and radionuclide methods. Several studies have suggested that the cyclic variation of myocardial integrated backscatter reflects myocardial viability rather than contractile reserve. The cyclic variation of integrated backscatter is associated with myocardial viability confirmed by the integrity of the microvasculature identified by contrast echocardiography. In addition, the cyclic variation of integrated backscatter better reflects myocardial viability confirmed by the integrity of cellar metabolism than contractile reserve. SUMMARY: Ultrasonic tissue characterization with integrated backscatter is a useful non-invasive method that can provide unique information for the assessment of myocardial viability.     

Ultrasonic tissue characterization of normal and ischemic myocardium

Cardiac ultrasonic tissue characterization is designed to use the alterations in acoustic signals from the myocardium to differentiate normal from ischemic or infarcted tissue due to their characteristic backscatter attenuation. Various approaches such as use of a gray scale, color display, or quantitative image analysis have been used for tissue characterization, but all depend on subjective assessments and are not necessarily reproducible. The most promising method has been the use of "raw" radiofrequency signals and measure changes in the ultrasonic attenuation with an index of backscatter to distinguish normal from abnormal myocardium called "integrated backscatter" (IB). Various studies have demonstrated the changes in the ultrasonic backscatter with ischemia or infarction. In this review we summarize our experience with a research prototype instrument in tissue characterization and differentiation of normal, ischemic, infarcted, and post ischemic reperfused myocardium in anesthetized open chest dogs. Currently we are investigating the role of ultrasonic tissue characterization to estimate infarct size and plan to apply these observations to patients in order to detect viable myocardium and quantitate infarct size.     

超声组织定征在心血管疾病诊断中的应用

超声组织定征(Ultrasonic Tissue Characterization,UTC)技术是通过检测组织的声学参数来定量描述正常和病理组织的物理(声学)特性。研究表明,背向散射积分作为组织定征的参数,可以识别缺血心肌、顿抑心肌、梗死心肌、左心室心肌肥厚及心脏移植排斥反应,评价和分析系统性疾病如糖尿病等引起的弥漫性心肌受累的状态、心腔内血栓和动脉斑块的成份等。因而UTC技术具有很大的临床价值和发展潜力,将成为常规超声心动图诊断的辅助手段。本文就超声组织定征技术在心血管疾病诊断中的应用及进展作一综述。     

Recent experience with ultrasonic tissue characterization

The current effort in the research laboratory at Stanford University Medical Center attempts tissue characterization using the parameter of cyclic variation of integrated ultrasonic backscatter (CVIBS). This parameter is available using prototype equipment that concentrates on the relative change in ultrasonic backscatter rather than the absolute level of backscatter measured. The interobserver reproducibility is quite good. The magnitude of CVIBS is greater in the posterior wall than in the septum generally. There is a weak association of aging with the magnitude of CVIBS. Measurement of CVIBS in patients with uncomplicated pressure overload hypertrophy and those with hypertrophic cardiomyopathy shows values in the posterior wall to be similar for all groups; however, the values for the septum were significantly smaller in patients in both hypertrophy groups compared with normal subjects. Studies in human cardiac allografts for the recognition of acute rejection have been carried out using CVIBS. A decrease in the magnitude of this parameter during rejection, compared to the baseline level, was characteristically seen. Return to prerejection levels was not invariably seen. Among the different systems for ultrasonic tissue characterization, the current system using CVIBS has been successful in specific studies.     

Transmural heterogeneity of myocardial integrated backscatter in diabetic patients without overt cardiac disease

It is important to detect early changes in diabetic myocardium, because some diabetic patients suffer from diabetic cardiomyopathy, especially those with poorer glycemic control or hypertension (HT). To clarify whether ultrasonic tissue characterization can noninvasively detect ultrastructural changes in diabetic myocardium, we analyzed the transmural heterogeneity in myocardial integrated backscatter (THIB) in 20 diabetic patients and 16 normal subjects. THIB was defined as the absolute value of difference of integrated backscatter between the endocardial and epicardial half of the myocardium. THIB in diabetic patients was significantly greater than that in normal subjects. In diabetic patients, there was a significant correlation between glycosylated hemoglobin and THIB, and the greater THIB was shown in patients with HT compared with those without HT. Early changes in the myocardium, related to increased interstitial collagen deposition or other occult cardiomyopathic changes, may be detected on the basis of quantitative analysis of THIB in diabetic patients.     

Normal Values in Children for Myocardial Ultrasonic Tissue Characterization by Integrated Backscatter

Normal values in adults for ultrasonic tissue characterization by integrated backscatter have been reported previously and subsequently applied to patients with specific diseases. Factors influencing integrated backscatter values in a pediatric population are not clearly defined. To obtain normal values for myocardial ultrasonic integrated backscatter in a pediatric population, we studied 72 children with normal cardiac anatomy using an ultrasonic integrated backscatter imaging system. The parameters measured were at peak, nadir, and end-diastole in eight different regions with two different settings: fixed and variable. We subsequently calculated cyclic variation, the ratios of cyclic variation to end-diastole and to peak. Age ranged from 1 day to 17.4 years (median 4.4 years). More than 90% of data curves from the two regions in the left ventricular posterior wall in long-axis view had normal patterns, whereas more than 50% of curves for the other regions had abnormal patterns. Comparing the two posterior wall positions, there were no differences in cyclic variation between the two regions, with little effect of setting. Less effect of regions and settings was noted for the ratios of cyclic variation to end-diastole or peak. There was no relation between backscatter variables and age, gender, or height, and some variables correlated weakly with body surface area. The assessment of integrated backscatter in children is optimal with interrogation of the left ventricular posterior wall imaged in the long-axis view. More stable estimates are obtained when the cyclic variation is related to the peak or end-diastolic value.     

Analysis of transmural trend of myocardial integrated ultrasound backscatter for differentiation of hypertrophic cardiomyopathy and ventricular hypertrophy due to hypertension

Objectives. This study was undertaken to differentiate hypertrophic cardiomyopathy from hypertensive hypertrophy using a newly developed M-mode format integrated backscatter imaging system capable of calibrating myocardial integrated backscatter with the power of Doppler signals from the blood.Background. Myocardial integrated ultrasound backscatter changes in patients with hypertrophic cardiomyopathy; however, it is unknown whether ultrasound myocardial tissue characterization may be useful in differentiating hypertrophic cardiomyopathy from hypertensive hypertrophy.Methods. Calibrated myocardial integrated backscatter and its transmural gradient were measured in the septum and posterior wall in 31 normal subjects, 13 patients with hypertensive hypertrophy and 22 patients with hypertrophic cardiomyopathy. The gradient in integrated backscatter was determined as the ratio of calibrated integrated backscatter in the endocardial half to that in the epicardial half of the myocardium.Results. Cyclic variation of integrated backscatter was smaller and calibrated myocardial integrated backscatter higher in patients with hypertrophied hearts than in normal subjects, but there were no significant differences in either integrated backscatter measure between patients with hypertensive hypertrophy and those with hypertrophic cardiomyopathy. Transmural gradient in myocardial integrated backscatter was present only in patients with hypertrophic cardiomyopathy (5.0 +- 1.8 dB [mean +- SD] for the septum; 1.2 +- 1.6 dB for the posterior wall).Conclusions. Hypertrophic cardiomyopathy and ventricular hypertrophy due to hypertension can be differentiated on the basis of quantitative analysis of the transmural gradient in integrated backscatter.