Application of tissue Doppler imaging in cardiology

Tissue Doppler imaging (TDI) is a new echocardiographic technique employing the Doppler principle to measure the velocity of myocardial segments and other cardiac structures. It is well suited for the measurement of long-axis ventricular function. Impairment of longitudinal myocardial fiber motion is a sensitive marker of early myocardial dysfunction and ischaemia, and TDI might therefore become an important tool in routine echocardiography. The technique allows truly quantitative measurement of regional myocardial function both at rest and during stress echocardiography. TDI has great potential in the diagnosis of diastolic left ventricular dysfunction, overcoming the load-dependence of conventional Doppler techniques. Right ventricular function, intracardiac and pulmonary artery pressures, transplant rejection and intraventricular dyssynchrony can also be assessed. This article reviews the current and evolving applications of TDI in cardiology.     

Doppler tissue imaging in myocardial infarction

BACKGROUND: The Doppler Tissue Imaging (DTI) is a recent Doppler method that allows to measure the velocities of myocardial walls. Thus, DTI may analyse myocardial contraction and give a quantitative evaluation of systolic and diastolic function. The aim of the study is to appraise the myocardial contraction of the left ventricle in patients with a recent myocardial infarction (MI) comparing data of standard echocardiography with those of DTI. METHODS: Fifteen patients with recent uncomplicated MI (22+/-6 days from the study) and 10 normal subjects have been studied. All population studied underwent bidimensional echocardiography with DTI analysis of different myocardial segments. RESULTS: In the infarcted patients, myocardial velocities were significantly reduced in comparison with the normal subjects in systole and in diastole. In patients with MI the picks of systolic velocities of normokinetic segments were significantly higher than those of akinetic/diskinetic segments (p<0.05). CONCLUSION: In myocardial infarction, the contraction of left ventricle is altered and it can be analysed and quantified through of the new indexes of systolic and diastolic myocardial function furnished by the DTI.     

Resting myocardial dysfunction in cirrhosis quantified by tissue Doppler imaging

Background: Cirrhotic cardiomyopathy is described as latent cardiac failure. However, it remains to be investigated whether the myocardial dysfunction is present even at rest. Aims: The aim of the present study was to quantify left ventricular function at rest by means of tissue Doppler imaging in patients with cirrhosis and relate the findings to liver status and cirrhosis aetiology. Methods: Forty‐four consecutive patients and 23 age‐matched healthy controls were included. Conventional echocardiographic‐ and tissue Doppler‐derived indices of systolic and diastolic function were obtained. Liver function was quantified by the galactose elimination capacity and clinical stage by the Child–Pugh and MELD scores. Results: Both systolic and diastolic myocardial functions were compromised in the patients at rest. Left ventricular ejection fraction (56.4 ± 6.1 vs. 59.9 ± 3.9%, P<0.02), mean peak systolic tissue velocity (4.6 ± 0.9 vs. 5.6 ± 0.7 cm/s, P<0.001) and mean systolic strain rate (?1.23 ± 0.19 vs. ?1.5 ± 0.14/s, P<0.001) were all reduced in cirrhosis patients. Thirty‐four patients (54%) had diastolic dysfunction, 11 had impaired diastolic relaxation pattern (25%), 12 had the more severe pseudonormal filling pattern (27%) and one had restrictive filling or severe diastolic dysfunction (2%). None of the echocardiographic findings were related to the cirrhosis aetiology. Conclusion: Tissue Doppler imaging during rest detected substantial systolic and diastolic myocardial dysfunction in cirrhotic patients. This supports the existence of a distinct cirrhotic cardiomyopathy.     

Pulsed Doppler tissue imaging and myocardial function in thalassemia major

 Few studies are available on left ventricular diastolic function in β-thalassemia major, and these have conflicting results. Our aim in this study was to analyze myocardial systolic and diastolic functions in patients with β-thalassemia major using, for the first time, pulsed Doppler tissue imaging (DTI), and compare data with standard Doppler echocardiography. We studies 30 young patients with β-thalassemia major (age ≤16 years) with normal left ventricular systolic function and in 30 age and sex-matched controls using pulsed DTI, and compared the data with standard data obtained with Doppler echocardiography. In the β-thalassemia major group before transfusion, early (E) and late (A) peak diastolic flow velocities were increased when compared with controls (P = 0.0032 and P = 0.0039, respectively). The E/A ratio did not differ between the groups. All DTI parameters in the patients were similar to those of controls, except for lateral annulus ejection time adjusted for heart rate, that was significantly reduced when compared with healthy subjects (P < 0.01). Multivariate analysis showed that ejection time adjusted for heart rate, has a significant relation with only E peak velocity (P < 0.01) and left atrial size (P < 0.01), two volume-dependent parameters. Our study shows that pulsed DTI parameters and standard Doppler left ventricular filling pattern in young β-thalassemia major patients with normal left ventricular systolic function are similar to those seen in conditions of increased preload. Received: July 12, 2002 / Accepted: October 25, 2002 Present address: Via A. Omodeo 45, 80128 Napoli, Italy Tel. +39-081-579-0262; Fax +39-081-560-5648 e-mail: giodisal@katamail.com Correspondence to G. Di Salvo     

Time intervals and myocardial performance index by tissue Doppler imaging

The application of tissue Doppler imaging (TDI) has shown remarkable growth in clinical practice during the past few years, especially, in risk stratification of patients with coronary heart disease or heart failure (systolic and diastolic). Myocardial performance index (MPI) is a Doppler echocardiographic parameter defined as the sum of the isovolemic contraction and relaxation times divided by the ejection time. It is considered as a reliable parameter to assess global left ventricular function. Cardiac time intervals and MPI have also been found as new applications in diagnosing cardiotoxicity from chemotherapy, COPD, valvular heart disease, pulmonary hypertension and endocrinopathies.     

多普勒组织成像技术在心肌梗死心功能评价中的应用

目的:研究多普勒组织成像(DTI)技术评价心肌梗死的临床应用价值。方法:回顾性分析应用DTI及彩色多普勒超声心动图(UCG)检查30例急性心肌梗死(AMI)患者的资料。结果:①AMI后2周,3个月,6个月时左室舒张功能显著减退(P<0.01),而左室收缩功能在2周时显著降低(P<0.01),随时间的推移略有改善;②AMI患者DTI速度图显像能更直观反应梗死相关局部的心肌室壁病变;③AMI患者2周时DTI频谱图特征:收缩波,舒张早期波E波和E／A(舒张晚期波)振幅比值降低(P均<0.01)。结论:DTI技术为观察AMI后心肌的室壁运动,心脏的收缩和舒张功能提供了一个直观,而且重复性好的有效方法。     

Comparison of myocardial tissue velocities measured by two-dimensional speckle tracking and tissue Doppler imaging

Myocardial velocities have prognostic implications, and transmitral E wave to mitral annular early diastolic tissue velocity ratio (E/Em) is utilized to estimate left ventricular (LV) end-diastolic pressure (EDP). There are no reference values for 2-dimensional (2D) speckle tracking myocardial velocities (S(2D), E(2D), A(2D)), and it is unknown if they are comparable with color tissue Doppler imaging (TDI). Predictors of E/E(2D) ratios are unknown and E/E(2D) has not been validated with LVEDP. The myocardial velocities of 142 subjects were measured by TDI and 2D speckle tracking. Mean E/Em and E/E(2D) were calculated as transmitral E wave to mean 6 basal early diastolic myocardial velocities using TDI and 2D speckle tracking respectively, and compared with LVEDP during catheterizations (n = 20). Mean E(2D) was lower but mean S(2D) and A(2D) were higher than TDI (all p <0.001). When TDI sample volume was tracked throughout the cardiac cycle, this directional difference was no longer apparent with S(2D), E(2D), and A(2D) higher than TDI (all p <0.05). Age, systolic blood pressure, LV ejection fraction, and mean S(2D) were independent correlates of E/E(2D). Receiver-operator characteristic analysis showed E/E(2D) (p = 0.03), not E/Em, identified elevated LVEDP (>/=12 mm Hg). E/E(2D) of 11.6 had 83% sensitivity and 70% specificity to predict elevated LVEDP. In conclusion, TDI and 2D speckle tracking myocardial velocities are not comparable due to angle independency and ability for tissue tracking with the latter. LV systolic function, age, and afterload are independent correlates of E/E(2D). Only E/E(2D) identifies elevated LVEDP, and an E/E(2D) of 11.6 has the optimal sensitivity and specificity.     

Quantification of longitudinal myocardial velocities by Doppler tissue imaging during dobutamine echocardiography

Doppler tissue imaging has been suggested to be a valuable method for the diagnosis of myocardial ischaemia during dobutamine echocardiography. The authors studied this mode of investigation in 49 consecutive patients (average age 60 +/- 12 years) referred for dobutamine stress echocardiography and who had undergone coronary angiography. The stress echo was carried out according to a standard protocol (5 to 40 m g/kg/min +/- atropine) with additional acquisition of 3 apical views (4, 2 and 3 chambers) with colour Doppler tissue imaging. Analysis of systolic and diastolic myocardial velocities was performed afterwards from digitised data. The different Doppler tissue parameters were measured in 12 left ventricular segments (excluding the apical segments) for each dosage of dobutamine: peak systolic velocity (S), Q-S duration, systolic velocity time integral (ITVS), peak early diastolic velocity (E), peak end diastolic velocity (A). These parameters were analysed throughout the stress for each segment without significant coronary stenosis to define normal values. ROC curves were constructed to determine threshold values of relative changes of velocity (between maximal dobutamine dosage and basal conditions) to improve detection of ischaemia in a segment with coronary stenosis (vessel diameter reduction > or = 70%). Similar diagnostic performances were observed with different systolic and diastolic parameters. The feasibility of measurement of diastolic velocities was, however, reduced (from 29% to 49%). The diagnostic accuracy of each parameter was the same for each vessel territory. A satisfactory concordance was observed between 2D echocardiography and Doppler tissue imaging for the detection of significant coronary stenosis in an analysis by vascular territory. The authors conclude that analysis of myocardial velocities during dobutamine stress echocardiography is feasible. It may be a useful complement for the detection of coronary stenosis during pharmacological stress echocardiography.     

Prognostic value of tissue Doppler echocardiographic imaging in elderly patients with acute myocardial infarction

Background: The ratio of mitral end‐diastolic velocity and mitral annular early diastolic motion velocity (E/e’) has predictive value in patients with acute coronary syndromes (ACS). Both E and e’ velocities change with age. The prognostic value of E/e’ in elderly patients with ACS has not been established yet. The aim of the study was to assess the prognostic significance of E/e’ in patients over 65 with ACS. Method: The study involved 168 patients, mean age 79 years. Echocardiography was performed within first 24 hours of ACS. Clinical evaluation, 6‐minute walk test, echocardiography and plasma level of NT pro‐BNP were performed 12 months later. Results: Patients, who were still alive after 1‐year follow‐up had significantly lower E/e’ during hospitalization: 11.1 ± 3 versus 15.1 ± 5 (P < 0.05). The optimal cutoff value of E/e’ differentiating survivors and nonsurvivors after 12 month follow‐up was 12. Initial E/e’ was an independent predictor of mortality during 1‐year follow‐up. E/e’ ratio during hospitalization significantly correlated with NT pro‐BNP concentration (r = 0.48, P < 0.001) and 6‐minute walking distance: (r =–0.32, P < 0.05) after 1‐year follow‐up. Conclusions: (1) In patients over 65 with myocardial infarction, E/e’ above 12 is an independent predictor of death during 1‐year follow‐up. (2) E/e’ ratio in acute phase of myocardial infarction correlated significantly with N pro‐BNP level and 6‐minute walking distance after 1‐year follow‐up. (Echocardiography 2011;28:298‐302)     

多普勒组织成像评价正常人心肌舒缩运动速度

目的　探讨心肌舒缩运动变化的相关因素。方法　标准切面 (左心室长轴、短轴 )用脉冲多普勒组织成像(DTI)测定室间隔、前壁、下后壁的内膜下心肌及外膜下心肌运动峰值速度。结果　各个室壁及各层心肌收缩期 s峰值速度不相同。内膜下心肌的 s峰值速度大于外膜下心肌的 s峰值速度 ,室间隔左心室面 s峰值速度大于右心室面 s峰值速度 ,两者间存在速度阶差。长轴左心室后壁 s峰值速度大于室间隔 s峰值速度 ,短轴后壁 s峰值速度大于前壁 s峰值速度。 s峰值速度与年龄无相关 ,舒张期 a峰值速度与年龄呈中度相关 ,e/ a比与年龄呈中度负相关 ,室壁运动的 e/ a比与二尖瓣血流 E/ A比呈中度相关。结论　脉冲 DTI可用于评价心肌的舒缩功能     

Disagreement between tissue Doppler imaging and conventional pulsed wave Doppler in the measurement of myocardial performance index.

AIM: Myocardial performance index (MPI) is usually measured with pulsed wave Doppler (PWD). Our aim was to assess the degree of agreement between PWD and a method based on tissue Doppler imaging (TDI). METHODS AND RESULTS: Seventy-five patients with prior myocardial infarction and 20 healthy subjects underwent measurement of time intervals and MPI with PWD and pulsed TDI at septal and lateral sides of mitral annulus. MPI and TDI-MPI at septal side showed the best intraclass correlation coefficient (ICC=0.54; p<0.0005). Ninety-five percent interval of agreement ranged from -0.27 to 0.22. These differences were attributed to discrepancies in isovolumic contraction and relaxation times. In the healthy group the results were similar (ICC=0.44), although the 95% interval of agreement was lower (from -0.13 to 0.12). CONCLUSIONS: The agreement between PWD and TDI in the measurement of MPI is only moderate. This should be taken into account in the interpretation of studies in which TDI is used for this measurement.     

Value of pulsed Doppler tissue imaging for early detection of myocardial dysfunction with anthracyclines

The cumulative and definitive nature of chronic cardiotoxicity of anthracyclines requires a preventive strategy of early diagnosis. The authors undertook a prospective study of the association of echocardiography, mitral Doppler and pulsed Doppler tissue imaging of the left ventricular lateral and posterior walls in the context of this problem in 20 patients without cardiac disease undergoing cancer chemotherapy including anthracyclines. Doppler echocardiography was performed before the first session of chemotherapy and at the end of treatment, 6 +/- 4 months later. After a total cumulative dose of 227 +/- 91 mg/m2 of doxorubicine, there were no changes in left ventricular ejection fraction but a significant decrease in mitral E wave velocity (p = 0.04) and in E/A ratio (p = 0.01), suggesting early changes in left ventricular relaxation. The Doppler tissue examination confirmed the presence of radial and longitudinal abnormalities in myocardial relaxation (decreases in myocardial E wave velocities of the posterior and lateral walls of the left ventricle, p = 0.02 and p = 0.01, respectively). The peak velocity of the myocardial systolic wave (Sm) was significantly decreased in the lateral wall (p = 0.02) and approached statistical significance in the posterior wall (p = 0.07). These results suggest concomitant changes in myocardial systolic and diastolic function with moderate doses of anthracyclines. Therefore, pulsed Doppler tissue examination enables earlier detection of left ventricular cardiotoxicity with anthracyclines than classical echocardiographic parameters.     

组织多普勒观察冠状动脉旁路移植术后心肌功能的变化

目的 评价冠状动脉旁路移植(coronary artery bypass graft,CABG)后组织多普勒(tissue Dopplerimaging,TDI)所反映的心肌收缩、舒张功能的长期变化趋势.方法 55例稳定型心绞痛患者于CABG术前、术后1周、1月、1年分别记录二尖瓣环运动的组织多普勒指标.其中43例为体外循环CABG,12例为非体外循环CABG.另外选择20例正常人群设为对照组.结果 二尖瓣跨瓣血流频谱E/A在手术前、后无明显变化,组织多普勒显示左心室舒张功能在术后1年内显著改善[术前、术后1周、1月、1年时二尖瓣环舒张早期峰值分别为(6.7±2.6)cm/s, (7.1±2.6)cm/s, (7.7±2.1)cm/s, (8.2±2.3)cm/s,P<0.05],左心室收缩功能在手术前后无显著改变.体外循环与非体外循环CABG患者舒张功能改善情况并无区别.结论 稳定型心绞痛患者的左心室舒张功能在CABG后迅速改善,并在手术后1年内逐步增强.     

Technological advances in tissue Doppler imaging echocardiography

Tissue Doppler imaging is a recently introduced echocardiographic tool for measuring myocardial velocities. In this article the physical principles and different myocardial velocity imaging modalities are discussed. Examples of practical applications and clinical use of this non-invasive imaging technique are provided.     

Analysis and quantification of longitudinal contraction of the left ventricle in myocardial infarction. Value of Doppler myocardial tissue imaging

The authors compared the results of conventional 2D echocardiography and those of Doppler tissue imaging in 30 patients in the intensive care unit for acute pulmonary myocardial infarction and 10 normal control subjects, to assess the longitudinal contraction of the left ventricle. Echocardiography was performed in the apical 2 and 4 chamber views to analyse the septal, lateral, posterior and anterior left ventricular walls. Each wall was divided into 3 segments: basal, median and apical. Each segment was scored: 1-normo or hyperkinetic, 2-hypokinetic, 3-akinetic and 4-dyskinetic. Doppler tissue imaging provided the maximum instantaneous velocities in systole and diastole in each segment. In control subjects, the myocardial velocities decreased significantly from the base to the apex, resulting in a systolic and diastolic pressure gradient with each wall between the base and the apex. In patients with myocardial infarction, the myocardial velocities were decreased compared with the control group. Moreover, the myocardial velocity gradient between the base and apex was significantly reduced in the hypo and akinetic walls, both in systole and diastole. These results show that, in myocardial infarction, the longitudinal left ventricular contraction is abnormal and may be analysed and quantified by new indices of myocardial systolic and diastolic function, provided by Doppler tissue imaging.     

First case of myocardial metastasis of an epidermoid tumor. Value of Doppler tissue imaging

The authors report the first case of a poorly differentiated epidermoid oesophageal cancer with myocardial metastasis. The diagnosis of malignant invasion of the myocardium was made by transthoracic echocardiography with electrocardiographic changes of subepicardial ischaemia. The authors review the literature of metastasic cardiac disease after the study of this particular case and underline the value of Doppler tissue imaging for myocardial characterisation.