Assessment of Left Ventricular Systolic Function Using Color-Coded Tissue Doppler Echocardiography

Tissue Doppler echocardiography can be used to measure myocardial velocity data by using the Doppler shift data of ultrasound waves. Two methods have recently been described to calculate velocity data: pulsed tissue Doppler and color-coded tissue Doppler. This article focuses on color-coded tissue Doppler data to evaluate left ventricular systolic function. Technical considerations and validation studies are reviewed. Potential clinical applications of color-coded tissue Doppler are presented, including dobutamine stress echocardiography, assessment of left ventricular ejection dynamics using mitral annular velocity, and tissue Doppler assessment of cardiac transplant rejection.     

超声心动图评价左心室功能的研究进展

左室功能的准确测定对临床诊断和治疗有着重要意义,超声心动图是目前最常用于测量左室功能的工具,其具有无创、廉价、重复性好等优点,更为重要的是它不仅可用于评价左室整体收缩功能,还能更加完善地评价左室舒张功能和局部心肌运动,现对近年来超声心动图评价上述心功能的主要方法进行回顾。     

Three-Dimensional Echocardiography in Evaluation of Left Ventricular Indices

Accurate determination of left ventricular mass, volume, ejection fraction, and wall motion is important for clinical decision making. Currently, M-mode and two-dimensional echocardiography (2DE) have been routinely used for this purpose. Although these 1D or 2D modalities provide excellent diagnostic and prognostic information, they have a number of technical limitations including the time required to perform the procedure and operator-dependent image acquisitions. In addition, they are inherently limited by geometric assumption of three-dimensional (3D) left ventricular structures based on 2D slices. With the improvement in transducer technology and software development, 3D echocardiography (3DE) has become widely available. Left ventricular quantitation by 3DE has been demonstrated to be accurate by multiple studies that compared 3DE with reference techniques. In addition, 3DE measurements were found to be more reproducible and less variable than 2DE. Real time 3DE imaging has potential advantages in stress echocardiography including rapid acquisition, unlimited number of planes, avoidance of foreshortening, and precise segment matching. This is a major step forward in our diagnostic armamentarium for the evaluation of ischemia. In this review, we summarized the current evidence of 3DE for left ventricular evaluation. (Echocardiography 2012;29:66-75)     

三维超声心动图在心功能评价中的应用现状

心功能的准确评价对心脏病患者的治疗、预后具有重要意义。三维超声心动图(3 dimensional echocardiography,3DE)能准确测量心功能而无需依赖几何形状的假设,是超声领域的重大突破。     

Assessment of Left Ventricular Volumes and Function by Real Time Three‐Dimensional Echocardiography in a Pediatric Population: A TomTec versus QLAB Comparison

Background: Three‐dimensional echocardiography (3DE) allows accurate calculation of ventricular volumes despite a remaining geometric assumption on the ventricular shape. Few studies involving full volume reconstruction software have been performed on children. Our aim was to compare the left ventricular (LV) volume measurements obtained with the most used 3D analysis software in a pediatric population. Methods: Fifty patients (median age: 9.5 years) without cardiac disease were included in the study. 3DE was performed with the X4–2 or X7–2 matrix probe (ie33, Philips). The LV volume analysis was performed with QLAB 6.0 (semiautomated border detection) and TomTec 4D LV (primary manual tracking with semiautomated border detection). Results: TomTec analysis feasibility amounted to 94% whereas QLAB analysis feasibility only reached 80% (P = 0.037). The analysis time was shorter with QLAB than TomTec (5 ± 2 versus 6 ± 3 minutes, P < 0.05). The stroke volume, end diastolic and end systolic LV volume measurements performed on the 40 patients were strongly correlated (r > 0.97; P < 0.0001) with minimal bias. The LV ejection fraction was well correlated (r = 0.79; P < 0.0001). Conclusion: 3D LV volume quantification is feasible either by using manual or automated reconstruction software in a normal pediatric population. LV Measurements are well correlated. Differences in volume reconstruction algorithms provide specific software performance characteristics. TomTec is a more feasible method but requires a longer analysis time. Further studies are needed to validate the accuracy of the method to calculate enlarged LV volumes in patients with congenital heart diseases. (Echocardiography 2010;27:1263‐1273)     

Measurement of Left Ventricular Ejection Fraction by Real Time 3D Echocardiography in Patients with Severe Systolic Dysfunction: Comparison with Radionuclide Angiography

Aim: Measurement of left ventricular ejection fraction (LVEF) using real time 3D echocardiography (3DE) has been performed in subjects with preserved or modestly reduced systolic function. Our aim was to evaluate this technique in the subset of patients with severe systolic dysfunction. Methods and results: Consecutive patients with LVEF less than 0.35 at two-dimensional echocardiography were included. LVEF obtained by 3DE was compared to the value measured by radionuclide angiography (RNA). Real time full-volume 3DE was performed, with offline semiautomated measurement of LVEF using dedicated software (Cardioview RT, Tomtec) by a single observer blinded to the results of RNA. A total of 50 patients were evaluated, of whom 38 (76%, 27 males, age 69 ± 13 years) had a 3DE of sufficient quality for analysis. LVEF for this group was 0.21 ± 0.07 using 3DE and 0.27 ± 0.08 using RNA. The agreement between the two techniques was rather poor (r = 0.49; P < 0.001; 95% limits of agreements of −0.20 to 0.09). Truncation of the apex was observed in 6 of 38 (16%) patients. Conclusion: In patients with severe systolic dysfunction, 3DE shows poor agreement for measurement of LVEF as compared to RNA. There may be underestimation of up to 20% in absolute terms by 3DE. Accordingly, the two methods are not interchangeable for the follow-up of LV function. A limitation of 3DE may, at least in part, be related to the incomplete incorporation of the apical region into the pyramidal image sector in patients with dilated hearts. (Echocardiography 2010;27:58-63)     

Evaluation of Hemodynamic Determinants of Quantitative Tissue Doppler Echocardiography in the Assessment of Left Ventricular Function

The aim of the present study was to determine whether quantitative tissue Doppler echocardiography has a role in the assessment of left ventricular hemodynamics. Thirty patients with suspected or known heart disease, but no wall motion abnormalities, took part in the study. Quantitative tissue Doppler echocardiography was performed using new software for digital analysis of the tissue Doppler signal. Average systolic subendocardial (S1), subepicardial (S2), and transmural (S3) wall velocity data were obtained from the inferoposterior wall and compared with the hemodynamics, including high fidelity pressure readings. S1 and S3 rates were found to be most reliable, being directly related to the peak rate of left ventricular pressure rise (dP/dt_peak) and inversely to systemic vascular resistance (SVR) and resistance index (SVRI). The best correlation was between S1, dP/dt_peak, and SVRI (multiple regression analysis: r = 0.76, P < 0.0001; simple regression analysis relating S1 to dP/dt_peak/SVRI: r = 0.77, SEE = 0.25, P < 0.0001). Thus, wall velocity indices as defined in this study have promise to become helpful in guiding the therapeutic modulation of inotropy and afterload in patients with heart failure.     

实时三维超声参数在评价稳定性冠心病患者左心室舒张功能中的作用

目的探讨实时三维超声心动图（real—timethree—dimensional echocardiography,RT-3DE）技术在稳定性冠心病患者左心室舒张功能评价中的应用价值。方法将65例稳定性冠心病患者根据造影检查所示冠状动脉狭窄程度分组。应用RT-3DE技术获取患者左心室容积-时间曲线（volume—timecurve,VTC）,观察整体及各节段VTC形态,计算舒张早期峰值充盈率（peak filling rate,PFR）、平均充盈率（meanfillingrate,MFR）、1,3充盈分数（I／3 filling fraction,1／3 FF）等参数,比较组间差异,选择有效参数进行相关性分析,并计算ROC曲线下面积。结果RT-3DE所测左心室容积、射血分数、峰值射血率（peak ejection rate,PER）及MFR在各组患者中无明显差异。PFR、1／3 FF随着冠状动脉狭窄程度的加重逐渐降低．冠状动脉明显狭窄者与造影结果正常者相比较,差异具有统计学意义（P均〈0．05）。PFR、1／3 FF与E／E’比值及NT—proBNP浓度均呈负相关,1/3 FF相关性优于PFR（与E／E’比值,r=-0．751．P〈0．01;与NT—proBNP浓度,r=0．612,P〈0．01）。以1/3FF判断无显著冠状动脉狭窄（即狭窄程度〈70％）的曲线下面积为0．772（P=0．001）．95％置信区间为0．633—0．911。1/3 FF≥36．75％判断冠状动脉狭窄程度〈70％的敏感性为73％,特异性为76％。氨基末端脑钠肽前体（N—terminal pro—B—type natriuretic peptide,NT—proBNP）。结论RT-3DE可定性、定量反映稳定性冠心病患者左心室舒张功能的变化,1／3FF可在一定程度上检测此类患者初期出现的以舒张早期心肌弛缓异常为主的轻度舒张功能受损。     

2D and 3D Echocardiography of a Left Ventricular Diverticulum

A real time transthoracic 3D study of a left ventricular diverticulum established through a narrow orifice located between the aortic and mitral valves is presented. Diverticular morphology was reconstructed and its volumes were calculated by this technique for the first time in the literature.     

Segmental Contribution to Left Ventricular Systolic Function at Rest and Stress: A Quantitative Real Time Three‐Dimensional Echocardiographic Study

Objective: To assess the relative contribution of each myocardial segment to global systolic function during stress using real time three‐dimensional echocardiography (RT3DE). Background: During stress, global augmentation in contractility results in an increased stroke volume. The relative contribution of each myocardial segment to these volumetric changes is unknown. Methods: Full volume was acquired using RT3DE at rest and following peak exercise in 22 patients who had no ischemia and no systolic dyssynchrony on two‐dimensional (2D) stress echocardiography. The following were calculated at rest and peak stress: end‐diastolic volume (EDV), end‐systolic volume (ESV), stroke volume (SV), ejection fraction (EF), relative SV, and relative EF. Results: With stress, an increase in global EDV from 90.8 to 101.1 ml (P < 0.001), SV from 59 to 78.4 ml (P = 0.01), and EF from 65.6 to 78.4% (P = 0.001) was observed. ESV decreased from 31.8 to 22.7 ml (P < 0.001). Segmental analysis revealed significantly higher SV, relative SV, and relative EF for the basal anterior, basal anterolateral, and basal inferolateral segments compared with the apical septum and apical inferior segments at both rest and stress (P < 0.001). The SV, relative SV, and relative EF increased significantly from apex to mid to base at both rest and stress (P < 0.001). Conclusions: The relative volumetric contribution of each myocardial segment to global left ventricular systolic function at rest and stress is not uniform. The basal segments contribute more than the mid and apical segments. Specifically, the basal anterior, basal anterolateral, and basal inferolateral segments contribute the most to augmentation of left ventricular systolic function with exercise. (ECHOCARDIOGRAPHY 2010;27:167‐173)     

The Relationship of Left Ventricular Trabeculation to Ventricular Function and Structure Over a 9.5-Year Follow-Up : The MESA Study

Background

Left ventricular (LV) trabeculation is highly variable among individuals and is increased in some diseases (e.g., congenital heart disease or cardiomyopathies), but its significance in population-representative individuals is unknown.

Objectives

The goal of this study was to determine if excessive LV trabeculation in population-representative individuals is associated with preceding changes in cardiac volumes and function.

Methods

For technical reasons, the extent of trabeculation, which is expressed as the ratio of noncompacted to compacted (NC/C) myocardium, was measured on cardiac magnetic resonance (CMR) long-axis cine images in 2,742 participants in the MESA (Multi-Ethnic Study of Atherosclerosis) (mean age 68.7 years; 52.3% women; 56.4% with hypertension; 16.8% with diabetes) at examination 5. These were considered in quintiles of trabeculation extent; the NC/C ratio of quintile 5 was 2.46 to 5.41. We determined the relationship between the maximal NC/C ratio and the preceding change (9.5 years between examinations 1 and 5) in end-systolic volume indexed (ESVi) to body surface area. Secondary analyses assessed the associations between the maximal NC/C ratio and preceding changes in end-diastolic volume indexed (EDVi) to body surface area and the ejection fraction (EF).

Results

Over 9.5 years, the ESVi decreased by 1.3 ml/m², the EDVi decreased by 5.1 ml/m², and the EF decreased by 0.6% (p < 0.0001). Even in subjects with excessive trabeculation, there were no clinically relevant differences in LV volumes and systolic function changes among the quintiles of trabeculation extent.

Conclusions

Greater extent of, and even excessive, LV trabeculation measured in end-diastole in asymptomatic population-representative individuals appeared benign and was not associated with deterioration in LV volumes or function during an almost 10-year period.     

Semiautomatic Quantification of Left Ventricular Function by Two‐Dimensional Feature Tracking Imaging Echocardiography. A Comparison Study with Cardiac Magnetic Resonance Imaging

Objective: To evaluate the accuracy of a semiautomatic quantification of left ventricular (LV) volumes and ejection fraction (EF) using two‐dimensional (2D) feature tracking imaging (FTI). Methods: Thirty‐four consecutive subjects (11 patients with dilated cardiomyopathy, 13 with hypertrophic cardiomyopathy, and 10 subjects with no cardiac disease) underwent, on the same day, trans‐thoracic echocardiography (TTE) examination, FTI, and cardiac magnetic resonance imaging (MRI), as gold standard, in order to quantify LV volumes and EF. The echocardiographic quantification of LV volumes and EF was determined from four‐ and two‐chamber views using both standard TTE Biplane Simpson's method and a semiautomatic border detection based on FTI. Furthermore, the time for data analysis for each method was measured. Results: The time required for semiautomatic analysis of volumes and EF was significantly lower (P < 0.0001) by FTI (71 seconds) in comparison with standard biplane Simpson's method (93 seconds). LV volumes obtained by FTI were significant underestimated (P < 0.001) in comparison with MRI. Bland‐Altman analysis of EDV and ESV using FTI and cardiac MRI showed a low level of agreement for EDV (mean difference = 40.8; SD = 39) and ESV (mean difference = 38.1; SD = 42). On the contrary, no significant difference between FTI and MRI in assessing the LVEF was found; furthermore, a very low bias (2 ± 12) by Bland‐Altman analysis was found between FTI and cardiac MRI for the quantification of EF. Conclusion: Semiautomatic quantification of LV volumes using FTI allows an accurate, rapid, easy and reliable assessment of LV EF and a rough estimation of LV volumes. (Echocardiography 2010;27:791‐797)     

高血压左室构型与心功能的关系

目的与方法本文采用二维和Ｍ型超声心动图方法,将２０９例高血压病人的左室构型与心功能进行比较。结果正常左室构型组、向心性重构组中,心功能Ⅰ级的百分比分别为７５．４％和６０．０％,向心性肥厚组及离心性肥厚组心功能Ⅰ级仅占１２．７％和１１．８％;向心性肥厚组左房明显增大（提示左室顺应性下降）,而离心性肥厚组左室收缩功能明显下降。结论临床上对不同的左室构型应采取不同的治疗措施     

Three-Dimensional Echocardiography: Precision and Accuracy of Left Ventricular Volume Measurement Using Rotational Geometry with Variable Numbers of Slice Resolution

We developed a new, rapid (6 seconds) acquisition technique allowing collection of approximately six through nine apical rotational tomograms for three-dimensional (3-D) echocardiography. To justify an appropriate sampling density for precise and accurate measurement of chamber volumes in left ventricles with complicated shape, we designed a validation study in vitro using six canine heart specimens with irregular, asymmetric left ventricles with known volumes (28.5 to 104.3 ml; mean, 71.2 ml). The number of equally spaced slices were incrementally deleted from the original high resolution scans (48 slices) to 2 slices in 3-D reconstruction. We created subgroups of 48- and 36-, 24- and 16-, 12- and 8-, 6- and 4-, and 3- and 2-component slices to compare left ventricular (LV) volumes measured in 3-D images with different slice resolution with the reference standard measured in the specimen. The accuracy and precision of LV volume were relatively constant in the subgroup of 4- and 6- through 36- and 48-component slices. When the subgroup with 6- and 4-component slices was used, the correlation was r = 0.991, P < 0.0001, root mean-square percent error of 5.0%, bias of 0.5 ± 3.7 ml, and interobserver variability of 5.0%. With the reduction in component slices equal or less than three, the accuracy decreased significantly (root-mean-square percent error = 8.1% and bias = -2.0 ± 5.7 ml) compared with higher slice resolutions. This study demonstrated that 3-D echocardiography using apical rotational techniques can accurately quantify LV volume in the canine heart specimens with irregular shapes with as few as 4–6 axial slices. The rapid 3-D acquisition technique is therefore anticipated to yield precise and accurate LV volumetry.     

Real Time Three‐Dimensional Echocardiographic Assessment of Left Ventricular Regional Systolic Function and Dyssynchrony in Patients with Dilated Cardiomyopathy

Purpose: To evaluate left ventricular (LV) regional systolic function and dyssynchrony in patients with dilated cardiomyopathy (DCM) by real time three‐dimensional echocardiography (RT‐3DE). Methods: The study population comprised 30 normal controls (NOR) and 44 patients with DCM. We divided the left ventricle into apical, middle, and basal regions. We calculated the LV regional end‐diastolic volume (_REDV), regional end‐systolic volume (_RESV), regional ejection fraction (_REF), and standard deviation in the time to minimal systolic volume in each level segment (Tmsv‐SD) of the three regions by RT‐3DE. Results: Compared with NOR, the _REDV, _RESV, and Tmsv‐SD of DCM were significantly higher, whereas the _REF was lower (P < 0.01). In DCM, the Tmsv‐SD increased smoothly from base to apex, and the _REF gradually decreased from base to apex (P < 0. 05). Linear correlation was observed between the Tmsv‐SD of the middle region and 3D‐EF in DCM (r =?0. 6829, P < 0.01). Conclusion: RT‐3DE provides a simple and feasible approach to quantify LV regional systolic function and dyssynchrony. (ECHOCARDIOGRAPHY 2010;27:415‐420)     

彩色M型多普勒超声评价高血压病人的左室舒张功能

目的 应用彩色M型多普勒超声心动图测量舒张早期左室内血流传播速度(vp)，评价高血压病人的左室舒张功能。方法 高血压组195例(50岁以下者23例；50—70岁者101例；70岁以上者71例)。正常对照组136例(如岁以下者53例；50—70岁者50例；70岁以上者33例)。取心尖四腔或二腔心平面测量左室内血流传播速度(Vp)，二尖瓣和肺静脉血流曲线。结果 高血压病人的Vp值较正常人降低(P＜0．01)，血流形态异常。结论 应用彩色M型多普勒超声心动图测量舒张早期左室内血流传播速度，不受心脏负荷及年龄的影响，作为评价高血压病人左室舒张功能的指标有临床意义。