Elusive left ventricular thrombus: Diagnostic role of cardiac magnetic resonance imaging-A case report and review of the literature

Identification of left ventricular mural thrombus (LVT) may be challenging depending on the imaging modality used. We present a case of LVT which was incidentally identified on cine cardiac magnetic resonance imaging (CMR). A sixty-four years old female presented with worsening dyspnea on exertion with troponin elevation. Transthoracic echocardiography (TTE) revealed a dilated left ventricle (LV) and ejection fraction (EF 30%) with thinning and akinesis of inferior/inferolateral wall was noted with basal and mid inferior wall aneurysm, and thrombus was not identified. CMR done to ascertain viability of myocardium revealed a mural thrombus within basal inferior aneurysm. This was not visualized on transthoracic echocardiography with and without use of contrast. She underwent coronary artery bypass grafting, bioprosthetic mitral valve replacement, resection and plication of posterior left ventricular aneurysm with removal of mural thrombus, and was started on anticoagulation with warfarin post-operatively for the apical thrombi. Cardiac magnetic resonance is a well suited imaging modality in detecting LVT due to its high resolution images and is more reproducible than TTE. In our patient, conventional TTE despite administration of echo-contrast agents failed to diagnose the presence of LVT in the basal inferior aneurysm as well as the apical thrombi. Delayed-enhancement CMR provides the greatest sensitivity for detection of left ventricular thrombus, superior to standard transthoracic and contrast-enhanced transthoracic echocardiography.     

实时三维超声心动图评价左室重构心功能的初步探讨

目的探讨实时三维超声心动图(RT-3DE)评价重构左室收缩功能的方法及可行性. 方法对26例不同病因所致左室形态重构的患者,应用RT-3DE采集左室腔立体数据库,测量左室舒张末期容积(EDV)、收缩末期容积(ESV)和左室射血分数(LVEF).同时应用二维超声(2DE)双平面Simpson's法和M型(ME)Teichholz法分别测量左室EF值.在心尖四腔、三腔和两腔心切面上,用ME记录二尖瓣瓣环在后间隔、侧壁、后壁、前间隔、下壁、前壁六个位点上运动的平均距离.分别比较RT-3DE与2DE、ME测值的相关性. 结果 RT-3DE能显示完整左室腔的立体形态.RT-3DE测定的LVEF值与二尖瓣瓣环运动的平均距离之间有很好的相关性(r＝0.9045,P<0.001),与二维法及M型法测量值之间相关性较低(r＝0.7355,r＝0.7218,P<0.01). 结论 RT-3DE为定量分析左室容积和收缩功能提供了一种无创的,准确可信的新途径.     

组织追踪MR技术评价正常人左室形变功能的临床研究

目的：采用心脏磁共振（cardiac magnetic resonance，CMR）电影序列的组织追踪技术探讨正常人左室应变。方法：随机入组2018年于复旦大学附属中山医院行CMR检查的健康志愿者39例，将影像学Dicom资料存盘后，应用CVI软件的组织追踪模块分析CMR电影序列图像，比较左室心肌形变指标基底段、中间段与心尖段的差别；内膜下与外膜下的差别；性别间、年龄分组间的差别。结果：39例健康志愿者左室内膜下、外膜下及整体心肌应变自基底段至心尖段递增；自心内膜下至心外膜下左室心肌应变递减，差异有统计学意义（P<0.05）；性别对左室应变无明显影响。结论：组织追踪MR可定量分析左室整体、节段与内膜下、外膜下心肌形变功能，为临床评价心脏功能提供新的依据。     

Incidence and predictors of left ventricular thrombus by cardiovascular magnetic resonance in acute ST-segment elevation myocardial infarction treated by primary percutaneous coronary intervention: a meta-analysis

Introduction

The incidence of left ventricular (LV) thrombus formation in ST-segment elevation myocardial infarction (STEMI) patients in the current era of primary percutaneous coronary intervention (PCI) is not well established. We performed a meta-analysis to assess the actual incidence and predictors of LV thrombus by cardiovascular magnetic resonance (CMR) in STEMI treated by primary PCI.

Methods

We searched MEDLINE and EMBASE databases up to February 2018. We included all studies published as a full-text article, reporting the incidence of LV thrombus by CMR within 1 month following acute STEMI in patients treated by primary PCI. A binary random-effects model was used to estimate the pooled incidence of LV thrombus. The diagnostic performance of transthoracic echocardiography (TTE) as compared with CMR was pooled to obtain the sensitivity and specificity of TTE with CMR as the gold standard. Embolic and bleeding complications of LV thrombus were also evaluated.

Results

Ten studies were included in the meta-analysis. The incidence of LV thrombus by CMR in all-comer STEMI patients (n?=?2072) was 6.3% with 96% of LV thrombus occurring in those with anterior STEMI (12.2% incidence). When only anterior STEMI with LVEF<?50% were considered (n?=?447), the incidence of LV thrombus was 19.2%. Compared with CMR, the sensitivity of TTE to detect LV thrombus was 29% with a specificity of 98%. The sensitivity of TTE increased to 70% in those with anterior STEMI and reduced LVEF. LV thrombus resolved in 88% of cases by 3 to 6 months. After 1–2 years follow-up, the embolic complication rate was similar at 1.5% (P?=?0.25) but the bleeding complication rate was significantly higher (8.8% versus 0.5%, P?<?0.001) in the LV thrombus group on triple therapy when compared to the no LV thrombus group on dual antiplatelet therapy.

Conclusion

In the primary PCI era, CMR detection of an LV thrombus post-STEMI remains high with incidence of nearly 20% in anterior STEMI with depressed LVEF. Patients with LV thrombus treated by triple therapy had similar embolic complications but higher bleeding complications than those with no LV thrombus treated with dual antiplatelet therapy. A 3 month follow-up CMR scan to guide anticoagulation duration might help mitigate bleeding risk.

     

二维应变超声心动图定量评价左心室整体和局部心肌应变的价值

目的探讨二维应变超声心动图（2D-SE）定量评价心肌局部和整体应变的临床应用价值。方法分别采集25例心力衰竭患者与30例正常对照者心尖左室长轴、心尖四腔和心尖左室二腔观的二维灰阶动态图像。应用自动功能成像软件自动测量长轴方向左室18节段收缩应变（εs）和心尖左室长轴观总应变（GLS-LAX）、四腔观总应变（GLS-A4C）、二腔观总应变（GLS-A2C）及左室长轴平均总应变（GLS-Avg）。同时采用二维Simpson法分别测量三个切面观的左室射血分数（2D-EF）。比较心力衰竭组与对照组各参数测值,分析2D-EF与二维应变（2D-GLS）的相关性。结果心力衰竭组18个节段的εS、GLS-LAX、GLS-A4C、GLS-A2C及GLS-Avg均显著低于正常组（P〈0.001）。2D-EF与2D-GLS有良好的相关性（r=0.94）。正常对照组各室壁自基底段向心尖段εS逐渐增加,各壁间差异无统计学意义;扩张型心肌病组各段室壁εS绝对值均明显低于正常对照组（均P〈0.05）,各节段间差异无统计学意义;前壁心肌死梗组中左前降支供血节段的εS绝对值明显低于正常对照组。结论2D-SE可用于定量测量左室整体和局部心肌的应变,为临床提供了一种快速准确、操作简便、可重复性好的无角度依赖的定量左室功能的新方法。     

Left ventricular mural thrombi secondary to acute myocardial infarction: predisposing factors and embolic phenomenon

Twenty-five patients with acute myocardial infarction were examined for ventricular thrombi using two-dimensional echocardiography. Six of 10 patients (60%) with an anterior wall infarction had an apical or apical-septal thrombus within the first week of hospitalization. None of the fifteen patients with an inferior wall myocardial infarction had a mural thrombus. Although the size of infarction in the patients with a thrombus was not significantly larger than in those who had an anterior wall infarction without a thrombus (43% +/- 10% vs. 31% +/- 7%, P less than 0.1), the severity and extent of dyskinesia or akinesia were more marked in the former group. Left ventricular function as determined by the nuclear blood pool scan ejection fraction was also significantly less for the former group than for the latter group (21% +/- 6% vs. 40% +/- 11%, P less than 0.02). Three of six patients with an intracavitary thrombus on echocardiography had systemic embolic during their hospital course. Postinfarction ventricular thrombi tend to occur in those patients with an anterior wall myocardial infarction who have far advanced wall motion abnormalities of the affected area, and overall poor left ventricular function. Although the number of patients was small, the high incidence of systemic embolization in the infarction subjects with echocardiographically proven thrombi indicates that these patients are at increased risk for such events.     

Usefulness of free-angle M-mode echocardiography in assessing left ventricular dimension and left ventricular systolic function

Objectives To assess the usefulness of free-angle M-mode echocardiography in measuring left ventricular (LV) dimension and global systolic function. Background The validity of conventional M-mode echocardiography in assessing LV dimension and global systolic function is well known; the incidental angle between the M-mode cursor and true LV minor axis diameter, however is a potential cause of measurement error. Free-angle M-mode echocardiography may overcome the limitation of M-mode cursor arrangement in conventional M-mode echocardiography. Methods Thirteen normal volunteers and 10 patients in whom abnormal left ventricular wall motion was not detected by echocardiography (mean age, 53±17 years) were enrolled in this study. Conventional and free-angle M-mode echocardiographic images of the LV were obtained by echocardiography (ALOKA SSD-5500) using a 2.5-MHz transducer, and the LV end-diastolic (LVDd) and end-systolic (LVDs) dimensions were measured by the leading edge method. LV end-diastolic and end-systolic volumes were calculated using a formula by Teichholz, and the LV ejection fraction (LVEF) was obtained. Data from conventional M-mode echocardiography and free-angle M-mode echocardiography were then compared. Results Measurements obtained with conventional M-mode and free-angle M-mode echocaardiography were strongly correlated. Correlation coefficients for LVDd, LVDs, and LVEF were 0.98, 0.98, and 0.96, respectively (p<0.001 in each case). Conclusions Assessment of left ventricular dimension, and global systolic function with free-angle M-mode can be as accurate as conventional M-mode in subjects in whom left ventricular wall motion abnormality is not detectable by echocardiogram. Moreover, when there is improper M-mode cursor direction in conventional echocardiography, free-angle M-mode echocardiography can assess global left ventricular systolic function more accurately and conveniently than conventional M-mode echocardiography.     

三维超声心动图对正常人左室局部收缩功能的评价

本文应用三维超声心动图系统对20例正常人左室进行了三维重建，并将重建后的左室进行断层和分区，研究其区域射血分数的变化，结果显示，正常人左心室收缩过程中，各部分收缩程度不一致，自心底到心尖部断层射血分数呈现增强趋势，将心脏断层分十二个区域，显示相当于心室前壁的部分区域射血分数较高。     

慢性肾功能不全患者左室局部收缩舒张功能的应变率成像研究

目的 探讨应变率成像评价慢性肾功能不全患者左心功能的价值.方法 传统超声心动图和应变率成像技术测量55例慢性肾功能不全患者与20例正常人(对照组),其中慢性肾功能不全患者依据肌酐清降率分为轻中度慢性肾功能不全组(22例)和重度慢性肾功能不全组(33例).取心尖四腔心、心尖二腔心各室壁(室间隔、外侧壁、下壁和前壁)的基底段测定收缩期应变率(Ssr),舒张早期应变率(Esr),舒张晚期应变率(Asr),4个室壁的平均值用来估测左室整体功能.结果 SR技术对病例组左心收缩功能不全检出率显著高于传统超声心动图(P<0.05),重度慢性肾功能不全组的Asr明显低于轻中度慢性肾功能不全组及对照组(F=3.567 P<0.05).结论 应变率能更加敏感地发现慢性肾功能不全患者左室功能障碍,重度慢性肾功能不全患者左心收缩功能损伤更明显.     

Clinical Utility of Cardiovascular Magnetic Resonance in Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is characterized by substantial genetic and phenotypic heterogeneity, leading to considerable diversity in clinical course including the most common cause of sudden death in young people and a determinant of heart failure symptoms in patients of any age. Traditionally, two-dimensional echocardiography has been the most reliable method for establishing a clinical diagnosis of HCM. However, cardiovascular magnetic resonance (CMR), with its high spatial resolution and tomographic imaging capability, has emerged as a technique particularly well suited to characterize the diverse phenotypic expression of this complex disease. For example, CMR is often superior to echocardiography for HCM diagnosis, by identifying areas of segmental hypertrophy (ie., anterolateral wall or apex) not reliably visualized by echocardiography (or underestimated in terms of extent). High-risk HCM patient subgroups identified with CMR include those with thin-walled scarred LV apical aneurysms (which prior to CMR imaging in HCM remained largely undetected), end-stage systolic dysfunction, and massive LV hypertrophy. CMR observations also suggest that the cardiomyopathic process in HCM is more diffuse than previously regarded, extending beyond the LV myocardium to include thickening of the right ventricular wall as well as substantial morphologic diversity with regard to papillary muscles and mitral valve. These findings have implications for management strategies in patients undergoing invasive septal reduction therapy. Among HCM family members, CMR has identified unique phenotypic markers of affected genetic status in the absence of LV hypertrophy including: myocardial crypts, elongated mitral valve leaflets and late gadolinium enhancement. The unique capability of contrast-enhanced CMR with late gadolinium enhancement to identify myocardial fibrosis has raised the expectation that this may represent a novel marker, which may enhance risk stratification. At this time, late gadolinium enhancement appears to be an important determinant of adverse LV remodeling associated with systolic dysfunction. However, the predictive significance of LGE for sudden death is incompletely resolved and ultimately future large prospective studies may provide greater insights into this issue. These observations underscore an important role for CMR in the contemporary assessment of patients with HCM, providing important information impacting diagnosis and clinical management strategies.     

犬左心室不同激动顺序收缩期容量与压力的超声研究

目的 应用三维全容积成像技术评价正常犬收缩期左事整体和节段容量及压力变化,评价不同电机械兴奋顺序时左室整体及节段收缩功能与同步化程度.方法 19只开胸比格犬模型,分别在基础状态(BASE)和右心耳(RAA)、右室心尖(RVA)、左室侧壁(LVL)、左室心尖(LVA)起搏状态采集左室全容积图像;同步记录左室流出道收缩末压力(ESP);脱机分析左室收缩末容积(ESV)、左室舒张末容积(EDV),计算整体及17节段射血分数(EF)、节段容积同步化指数(SDI)、左室收缩期压力平均上升速率(+dp/dt)和舒张期压力平均下降速率(-dp/dt).对各参数行配对t检验、方差分析和线性相关分析.结果 ①RVA组左室整体EF、ESP、+dp/dt、-dp/dt较RAA组减低,SDI较RAA组增大(P<0.05);LVL组及LVA组整体EF与RAA组问差异均无统计学意义(P>0.05),ESP,+dp/dt、-dp/dt均较RAA组减低,SDI均较RAA组增大(P<0.05).②LVL组及LVA组EF均较RVA组增高,LVL组SDI较RVA组减低(P<0.05),LVA组SDI与RVA组间差异无统计学意义.③LVL组整体EF、SDI、ESP、+dp/dt及-dp/dt与LVA组间差异无统计学意义;LVA组间隔、心尖节段EF较LVL组减低(P<0.05).④RVA组前、后间隔、心尖(除侧壁外)节段EF较RAA组减低(P<0.05);LVL组侧壁、前壁节段EF较RAA组减低;LVA起搏组前壁、前间隔、心尖节段EF较RAA组减低(P<0.05).⑤左室容积与压力参数间未能建立线性相关关系.结论 RAA起搏左室整体及少数节段收缩功能低于窦性心律;RAA起搏左室收缩与舒张功能均优于心室起博;LVL起搏左室收缩功能明显优于RVA起搏;心室起搏后,起搏位点周围左室节段收缩功能下降.     

A black mobile mass: diagnosis and management

The diagnosis and treatment of left ventricular apical thrombi after myocardial infarction are still not well stablished. Fibrinolytic treatment, Heparin treatment and surgical removal might be therapeutic options. We present the case of a 37 year old man who came into the Emergency department complaining of pleuritic chest pain. ECG revealed an evolving anterior wall infarction and transthoracic echocardiogram showed a big mobile thrombus in the ventricular apex. In order to confirm diagnosis and to differentiate other entities like pseudoaneurysm, contrast echocardiography and cardiac MRI with late gadolinium enhancement were performed and allowed a definitive diagnosis. Our patient was treated with intravenous heparin and then with oral anticoagulation. Two months later, echocardiogram showed an apical non-mobile and smaller thrombus.     

应用组织速度成像和组织追踪法评价川崎病患儿左心功能

目的应用定量组织速度成像和组织追踪法评价恢复期川崎病患儿左心功能状况。方法恢复期川崎病患儿30例(患病组)，正常儿童20例(正常组)。通过M型超声获得左室射血分数(LVEF)，通过二尖瓣口血流频谱获得二尖瓣口血流快速充盈速度(E)，左房收缩期速度(A)，计算E／A；应用定量组织速度成像和组织追踪分析软件测量心脏前间隔、后壁、前壁、下壁、后间隔和侧壁的二尖瓣环处收缩期峰值速度(Vs)、收缩期最大位移(D)、舒张早期峰值速度(Ve)、左房收缩期峰值速度(Va)，计算Ve／Va。并比较两组间各参数。结果患病组LVEF、E峰、A峰及E／A都在正常范围内，与正常组相比无统计学差异；各室壁的二尖瓣环处的Vs和D两组间差异有显著性意义，6个室壁的平均Vs和D两组间差异也有有显著性意义；各室壁的舒张速度Ve和Va以及Ve／Va，只在少数室壁两组间差异有显著性意义。结论川崎病恢复期左室整体收缩功能受损，舒张功能尚正常；组织速度成像技术能够定量评价小儿纵向左室功能改变。     

斑点追踪技术对急性前壁心肌梗死患者左心室扭转及解旋运动的研究

目的 应用斑点追踪技术(STI)评价急件前壁心肌梗死(AMI)患者左心室扭转及解旋运动的变化.方法 38例AMI患者根据左室射血分数(LVEF)分为两组:LVEF正常组(LVEF≥45%,21例)和LVEF减低组(LVEF<45%,17例).20例正常人作为对照组.取左室心尖和心底短轴二维图像,应用EchoPAC超声工作站进行脱机分析,计算左室扭转角度峰值(Ptw)、收缩末期扭转角度(AVCtw)、等容舒张末期扭转角度(MVOtw)、解旋率(UntwR)、扭转速度峰值(PTV)、扭转速度达峰时间(TPTV)、解旋速度峰值(PUV)和解旋速度达峰时间(TPUV).结果 与对照组及LVEF正常组相比,LVEF减低组Ptw、AVCtw、MVOtw、UntwR明显减低,差异均有统计学意义(P<0.05).三组之间PUV、PTV及TPTV差异无统计学意义(P>0.05).UntwR与LVEF及左室收缩末期容积有相关性.结论 STI技术可准确评价前壁AMI患者左室扭转及解旋.AMI患者LVEF减低组左室扭转角度及UntwR明显减低;左室扭转及解旋影响左窒收缩功能.     

Mean Myocardial Velocity Mapping in Quantifying Regional Myocardial Contractile Reserve in Patients with Impaired Left Ventricular Systolic Function: Doppler Myocardial Imaging Study

The aim of this study was to use Doppler myocardial imaging–derived mean myocardial velocity (MMV) at baseline and during low-dose dobutamine stress echocardiography (DSE) to quantify regional contractile reserve of the left ventricle (LV). Sixteen patients (mean age 59 ± 7 years) with coronary artery disease and regional left ventricular wall motion abnormalities were studied. During each increment of Dobutamine infusion, 6 2-dimensional transthoracic apical images were acquired in standard gray-scale and Doppler myocardial imaging modes at 30° steps over 180°. For the analysis, the LV was divided into 18 segments. For each segment, both wall motion score and MMV obtained in systole and both early and late diastole were measured at baseline and at each stage of DSE. In viable segments by wall motion score, MMV increased during DSE in systole and in early and late diastole. In contrast, in nonviable segments, MMV did not change during DSE. Mean myocardial velocity mapping is a promising new approach to quantify regional myocardial contractile reserve of the LV. (J Am Soc Echocardiogr 2000;13:96-107.)     

Longitudinally and circumferentially directed movements of the left ventricle studied by cardiovascular magnetic resonance phase contrast velocity mapping

Objective

Using high resolution cardiovascular magnetic resonance (CMR), we aimed to detect new details of left ventricular (LV) systolic and diastolic function, to explain the twisting and longitudinal movements of the left ventricle.

Methods

Using CMR phase contrast velocity mapping (also called Tissue Phase Mapping) regional wall motion patterns and longitudinally and circumferentially directed movements of the left ventricle were studied using a high temporal resolution technique in healthy male subjects (n = 14, age 23 ± 3 years).

Results

Previously undescribed systolic and diastolic motion patterns were obtained for left ventricular segments (based on the AHA segmental) and for basal, mid and apical segments. The summation of segmental motion results in a complex pattern of ventricular twisting and longitudinal motion in the normal human heart which underlies systolic and diastolic function. As viewed from the apex, the entire LV initially rotates in a counter-clockwise direction at the beginning of ventricular systole, followed by opposing clockwise rotation of the base and counter-clockwise rotation at the apex, resulting in ventricular torsion. Simultaneously, as the entire LV moves in an apical direction during systole, the base and apex move towards each other, with little net apical displacement. The reverse of these motion patterns occur in diastole.

Conclusion

Left ventricular function may be a consequence of the relative orientations and moments of torque of the sub-epicardial relative to the sub-endocardial myocyte layers, with influence from tethering of the heart to adjacent structures and the directional forces associated with blood flow. Understanding the complex mechanics of the left ventricle is vital to enable these techniques to be used for the evaluation of cardiac pathology.     

二维应变超声心动图评价移植心脏左心室收缩功能

目的应用二维应变超声心动图检测移植心脏左室壁峰值收缩应变,探讨二维应变超声心动图评价移植心脏左室收缩功能的价值。方法9例心脏移植受者共进行41次超声检查;23例正常人作为对照。记录心尖长轴观、心尖两腔观及心尖四腔观的高帧频二维图像,应用二维应变分析软件测量左室壁各节段的峰值收缩应变及心尖各切面观心肌总的峰值收缩应变、左室整体平均峰值收缩应变。结果无排异反应的心脏移植受者与正常人相比,除了4个心尖节段（后壁心尖段、前间隔心尖段、侧壁心尖段、前壁心尖段）外,左室壁各节段峰值收缩应变均显著降低（P〈0.05）;心尖各切面观心肌总的峰值收缩应变及左室整体平均峰值收缩应变均较正常显著降低（P〈0.05）。急性排异反应与无排异反应的心脏移植受者后室间隔及侧壁各节段相比,峰值收缩应变均有下降趋势,但仅后室间隔心尖段峰值收缩应变降低具有统计学意义（P〈0.05）。急性排异反应的心脏移植受者心尖四腔观心肌总的峰值收缩应变较无排异反应的心脏移植受者则显著降低（P〈0.05）。结论二维应变超声心动图可用于快速准确评价移植心脏左室收缩功能,在排异反应诊断方面具有潜在价值。     

心肌肥厚性疾病患者左心室扭转与心肌纤维化的相关性研究

目的应用三维超声斑点追踪成像技术分析心肌肥厚性疾病患者左心室扭转与心肌纤维化程度的相关性。 方法收集2017年7月至2019年2月在哈尔滨医科大学附属第四医院行心脏超声及心脏磁共振（CMR）检查的心肌肥厚性疾病患者31例,根据CMR钆造影剂延迟强化阳性与否诊断患者是否存在心肌纤维化,并将患者分为心肌纤维化组20例,无心肌纤维化组11例。另选取健康体检者35例作为对照组。应用三维斑点追踪成像技术测量左心室基底段、中间段、心尖段旋转角度峰值,左心室整体扭力及左心室扭转角度峰值。比较心肌肥厚性疾病患者与健康对照组的常规二维超声参数,以及心肌肥厚性疾病心肌纤维化组、无心肌纤维化组与健康对照组的左心室旋转、扭转参数。分析左心室扭转角度峰值与钆造影剂延迟强化阳性心肌/左心室心肌质量比值的相关性。 结果与健康对照组比较,心肌肥厚性疾病无心肌纤维化组及心肌纤维化组的左心室基底段、中间段、心尖段旋转角度峰值及左心室扭转角度峰值均明显升高（无心肌纤维化组：t=4.45、7.51、-5.45、-6.79,心肌纤维化组：t=-5.53、-9.84、-5.82、-9.45;P均<0.01）;心肌肥厚性疾病心肌纤维化组左心室心尖段旋转角度峰值及左心室扭转角度峰值较无心肌纤维化组明显升高（t=-2.71、2.36,P均<0.05）。心肌肥厚性疾病患者左心室扭转角度峰值与钆造影剂延迟强化阳性心肌/左心室心肌质量比值呈正相关（r=0.58,P=0.001）。 结论三维斑点追踪技术可有效评估心肌肥厚性疾病患者左心室扭转及旋转,左心室整体扭转角度峰值与左心室心肌纤维化呈正相关,三维斑点追踪技术可为临床检测心肌肥厚患者心肌纤维化提供新的方法和选择。     

多巴酚丁胺负荷超声心动图对左室心尖部血栓与存活心肌的研究

目的 旨在探讨是否在常规2-DE左室心尖部血栓的出现预示无存活心肌的存在.方法 80例心肌梗死患者接受DSE检查,根据心室内有无血栓分为血栓组（1组）及无血栓组（2组）,比较两组的室壁运动积分及射血分数.结果 48例患者被证实/高度怀疑有左室血栓（1组）,32例患者无左室血栓（2组）.1组比2组有更高的室壁积分;1组的32（67%）例及2组中8（25%）例患者证明在心尖节段无收缩储备即无存活心肌.结论 在无存活心肌存在的相应节段左室心尖部血栓更易出现.     

Partial cut-off of the left ventricle: determinants and effects on volume parameters assessed by real-time 3-D echocardiography

A total of 44 patients with coronary artery disease underwent real-time three-dimensional (3-D) echocardiography for end systolic (ES) and end diastolic (ED) left ventricular (LV) volumetric analysis to assess the effect of partial cut-off of the left ventricular (LV) apex on volumetric analysis by apical transthoracic echocardiography. Patients with LV cut-off were assigned to either group 1 (ejection fraction, (EF) < 49%) or group 2 (EF > or = 49%). Patients were additionally classified as group A if they had anterior or apical wall motion abnormalities (WMA) or group B if they had only inferoposterior or lateral WMA. Partial LV cut-offs were found in 22 subjects (50%). The estimated end diastolic cut-off volumes were as follows: 8.6 +/- 3.2 mL (group 1), 4.3 +/- 2.4 mL (group 2), 9.1 +/- 3.3 mL (group A) and 1.4 +/- 0.8 mL (group B). In group 1, more patients with LV volume cut-off were found than in group 2: chi(2) = 4.52, p < 0.05; and in group A more than in group B: chi(2) = 8.08, p < 0.01. In all, partial LV cut-off led to underestimation of LV volumes: 5.9 +/- 4.7 ml (ED) vs. 2.1 +/- 1.3 ml (ES), p <0.02. In conclusion, LV cut-offs can potentially alter the accuracy of echocardiographic volumetric analysis, particularly in anterior or apical WMA.