Abnormal Global Left Ventricular Relaxation Occurs Early During the Development of Pharmacologically Induced Ischemia

In animal and human models, left ventricular (LV) diastolic function has been observed to be highly sensitive to myocardial ischemia. The response of LV diastolic parameters to pharmacologically induced ischemia, however, has not been characterized and might be important in the interpretation of dobutamine stress echocardiography. Eight mongrel dogs, in which were inserted a high-fidelity micromanometer LV catheter, coronary sinus sampling catheter, and ultrasonic coronary artery flow probe, underwent intravenous dobutamine infusion at escalating doses both before (control protocol) and after (ischemia protocol) creation of left anterior descending coronary artery stenosis with a hydraulic cuff occluder adjusted to maintain resting coronary artery flow but attenuate reactive hyperemia. At each dobutamine dose, epicardial short-axis 2-dimensional echocardiographic images and hemodynamic measurements were obtained. LV diastolic function was examined by calculation of peak (–)dP/dt and the time constant of isovolumic relaxation (τ). The dobutamine infusion protocol was terminated on the earliest recognition of an anterior wall motion abnormality. Peak (+)dP/dt normalized for developed isovolumetric pressure was calculated as a relatively load-independent index of global LV contractile function. Dobutamine infusion with and without ischemia resulted in comparable changes in heart rate and (+)dP/dt/IP, with no change in LV end-diastolic or -systolic pressure. The magnitude of peak (-)dP/dt increased less during the ischemia (1231 ± 109 to 1791 ± 200 mm Hg/sec) versus the control (1390 ± 154 to 2432 ± 320 mm Hg/sec) protocol (P < .05). Similarly, the observed decrease in τ was less during the ischemia (53 ± 3 to 38 ± 4 msec) than the control (51 ± 5 to 23 ± 3 msec) protocol, corresponding to a slower rate of relaxation (P < .05). In addition, the smaller decrease in τ was observed at the dobutamine dose before the dose at which an echocardiographic wall motion abnormality was first recognized. Dobutamine-induced ischemia is associated with abnormal LV diastolic function. In addition, these abnormalities seem to occur early in the development of ischemia. These observations extend to pharmacologically induced ischemia prior findings from other models of ischemia, suggesting the high sensitivity of LV diastolic function to the development of myocardial ischemia. (J Am Soc Echocardiogr 1999;12:113-20.)     

Detection of left ventricular dysfunction by Doppler tissue imaging in patients with complete recovery of visual wall motion abnormalities 6 months after a first ST-elevation myocardial infarction

AIMS: The aim of this study was to assess left ventricular (LV) systolic and diastolic function, using Doppler tissue imaging (DTI), in patients with complete recovery of visual wall motion abnormalities six months after a first ST-elevation myocardial infarction (STEMI). METHODS: Out of 90 patients presenting with a STEMI, 68 patients without a history of heart disease were examined by echocardiography before discharge and after 6 months. The patients were compared to 41 age matched healthy subjects (HS). LV function was assessed by visual wall motion and mitral annular velocities using pulsed wave DTI. RESULTS: Sixty-eight patients had visual wall motion abnormalities at baseline. Of these, 19 patients showed complete recovery of wall motion at 6-months follow-up. Patients with complete recovery of wall motion abnormalities had significantly reduced peak systolic and peak early diastolic mitral annular velocities compared to HS at 6 months (8.3 cm s(-1) versus 9.9 cm s(-1), P<0.001 for systolic velocity and 9.3 cm s(-1) versus 13.1 cm s(-1), P<0.001 for diastolic velocity, respectively). CONCLUSION: In patients presenting with a first STEMI, mitral annular systolic and early diastolic velocities assessed by DTI at 6-months follow-up are significantly reduced compared to HS, despite normal standard echocardiographic parameters of LV function. This probably reflects a residual subendocardial damage not detected by conventional echocardiographic methods.     

Predicting left heart failure after a myocardial infarction: a preliminary study of the value of echocardiographic measures of left ventricular filling and wall motion

Heart failure occurs from both systolic and diastolic dysfunction. To determine whether simple Doppler echocardiographic measures of left ventricular filling could improve upon the ability of systolic function to predict heart failure after infarction, patients with acute myocardial infarction were studied within the first 36 hours by Doppler and two-dimensional echocardiography. Forty-eight patients who did not have heart failure before the Doppler echocardiographic study and who did not have myocardial revascularization, moderate or severe mitral regurgitation, or other complications during recovery were monitored for 6 months or to the onset of heart failure (n = 10). The univariate predictors of heart failure were age (p less than 0.05), anterior infarction (p less than 0.05), early diastolic peak filling velocity (p = 0.05), filling velocity with atrial systole (p less than 0.05), the ratio of these velocities (p less than 0.001), the percentage of filling with atrial systole (p less than 0.001), and the wall motion score index (p less than 0.001). However, the only independent predictors of heart failure by use of multivariant stepwise logistic regression analysis were the wall motion score index (p less than 0.05) and either the ratio of early and late peak filling velocities (p less than 0.001) or the percentage of filling with atrial systole (p less than 0.001). The combined use of a measure of systolic function and measures of the relative contribution of atrial systole to ventricular filling were useful predictors in identifying patients likely to develop subsequent heart failure after myocardial infarction.     

定量组织速度成像技术评价急性心肌梗死后左室重构的左室功能

目的应用定量组织速度成像技术对心肌梗死后左室重构的左心功能进行评价,以探讨其应用价值.方法用定量组织速度成像技术测定22例健康者及临床确诊的29例心肌梗死后左室重构的冠心病患者的左室壁各节段的收缩期峰值速度(VS),舒张早期速度(VE),舒张晚期速度(VA)和VE/VA比值.测定二尖瓣口血流频谱的快速充盈速度(E),左房收缩充盈速度(A)和E/A值.容积法测左室射血分数,左室舒张末期容积指数(LVEDVI),左室收缩末期容积指数(LVESVI)及球形指数,并与正常组比较.结果心脏左室长轴方向上心梗组前壁,侧壁,下壁各节段,后间隔心尖段Vs明显下降(P＜0.01),后间隔基底段和中间段Vs无明显差异(P＞0.05);心梗组几乎各节段VE、VA、VE/VA与正常组相比有显著差异(P＜0.05).各节段平均VS与左室射血分数,球形指数等呈线性相关(r值分别为0.79,0.68,P＜0.01),舒张期功能参数平均VE/VA与二尖瓣E/A比值之间存在高度相关性(r=0.62,P＜0.01).心梗组LVEDVI和LVESVI明显增大(P＜0.01).结论定量组织速度成像可客观定位定量的反映心肌梗死局部心肌组织的收缩及舒张功能,又能体现心肌梗死后左室重构的整体功能,为心肌梗死后左室重构的心功能的评价提供了客观依据.     

Left ventricular function in professional football players evaluated by tissue Doppler imaging and strain imaging

Background Long-term regular exercise is associated with physiologic and morphologic cardiac alterations. Tissue Doppler Imaging(TDI) and Strain Myocardial Imaging(SI) are new tools in the evaluation systolic and diastolic myocardial function. We sought to compare TDI and SI findings in professional football players and age adjusted sedentary controls to assess the effect of regular athletic training on myocardial function. Methods Transthoracic echocardiography, M-mode, 2-D measurements, Doppler derived mitral-tricuspid annular velocities, reconstructed spectral pulsed wave tissue Doppler velocities, strain and strain rate imaging of seven different myocardial regions were obtained from 24 professional football players and age, sex and weight adjusted 20 controls. Results Age, body surface area, blood pressure and heart rate were comparable between 2 groups. Football players had significantly increased LV mass, mass index (due to both higher wall thickness and end-diastolic diameter), end-systolic and end-diastolic volume, left atrial diameter and decreased transmitral diastolic late velocity. In athletes TDI analysis showed significantly increased mitral annulus septal TDI peak early diastolic(e) velocity(0.22 ± 0.04 vs. 0.19 ± 0.04 m/s, P < 0.05), lateral TDI peak e velocity (0.19 ± 0.03 vs. 0.16 ± 0.02 m/s, P < 0.05) and lateral TDI e/a ratio (1.96 ± 0.41 and 1.66 ± 0.23, P < 0.05). In SI analysis mid septal walls (1.71 ± 0.23 in athletes and 1.49 ± 0.25 in controls, P < 0.05) and mid lateral walls (1.55 ± 0.28 and 1.34 ± 0.25 respectively, P < 0.05) peak systolic strain rate values differences were found to be increased in athletes. Conclusions Professional football playing is associated with morphologic alteration in left ventricle and left atrium and improvement in left ventricle diastolic function which can be detected by TDI. Strain rate imaging may be a new tool to define subtle change in systolic left ventricular function in “athletes heart” which cannot be determined in standard echocardiographic parameters.     

The role of short- and long-axis function in determining late diastolic left ventricular filling in patients with hypertension: Assessment by pulsed Doppler tissue imaging

Left ventricular (LV) wall motion velocity during atrial systole is mediated by both transmitral flow and LV myocardial compliance at end-diastole. LV wall distensibility along the long- and short-axis during atrial systole and late diastolic LV filling may vary according to the remodeling of LV morphology. We measured LV wall motion velocities along the long and short axes using pulsed Doppler tissue imaging in 127 patients with hypertension to evaluate the relationship between the hemodynamic changes and LV morphology and to determine the role of both long- and short-axis function in late diastolic LV filling. Participants were classified into 3 groups according to LV dimension and end-diastolic wall thickness determined by M-mode echocardiography: group A (n = 62) without LV dilation or hypertrophy, group B (n = 55) with LV hypertrophy, and group C (n = 10) with LV dilation and systolic dysfunction. The time constant of the LV pressure decay during isovolumic diastole and the LV end-diastolic pressure were longest and greatest, respectively, in group C, compared with groups B and A. There were no significant differences in active left atrial emptying volume during atrial contraction determined by computerized echocardiographic 3-dimensional reconstruction among patient and control groups. The peak atrial systolic motion velocity of the LV posterior wall along the long axis was significantly lower in groups B and C, particularly in the latter group, than in group A. The peak atrial systolic motion velocity of the LV posterior wall along the short axis was greatest in group B and was lowest in group C compared with the other groups, respectively. The peak atrial systolic motion velocity of the LV posterior wall was greater along the long axis than the short axis in group A, but was less than the short axis in group B. In conclusion, the long- and short-axis function of the LV wall during atrial systole varies in patients with hypertension according to the severity of hemodynamic and morphologic abnormalities. The degree of LV wall expansion along the short axis is an important factor resulting from the atrial kick, and a determinant of its effectiveness. (J Am Soc Echocardiogr 2002;15:1211-7.)     

Tissue cardiovascular magnetic resonance demonstrates regional diastolic dysfunction in remote tissue early after inferior myocardial infarction.

PURPOSE: To investigate regional diastolic and systolic function using tissue cardiovascular magnetic resonance (CMR), early after transmural myocardial infarction of the inferior wall due to single proximal right coronary artery disease. MATERIALS AND METHODS: Velocity encoded CMR was used to measure early diastolic transmitral flow velocity (E), and regional, longitudinal, myocardial systolic (Sa) and early diastolic (Ea) velocities (tissue CMR) in 15 patients with a recent transmural inferior myocardial infarction and in 15 age and LV-mass index matched control subjects. An unpaired two-tailed t test was used to assess significance of continuous variables. RESULTS: Global systolic (ejection fraction 46 +/- 7% versus 57 +/- 4%, p = 0.000052) and global diastolic LV function (average Ea of infarcted or inferior, remote or anterior, adjacent or septal and lateral myocardium 6.8 +/- 1.7 cm/s versus 10.4 +/- 1.5 cm/s, p = 0.0000012) were impaired in patients as compared to controls. Regional systolic and diastolic LV velocities were impaired in infarcted and adjacent tissue in patients. However, in remote or anterior tissue, systolic velocities were preserved (Sa 6.6 +/- 2.0 cm/s versus 6.8 +/- 1.4 cm/s, p = 0.70), but diastolic velocities were impaired in patients as compared to controls (Ea 7.2 +/- 2.3 cm/s versus 10.2 +/- 2.5 cm/s, p = 0.0026). CONCLUSIONS: Regional diastolic velocities early after inferior myocardial infarction are impaired in the infarcted, adjacent and remote tissue, but regional systolic velocities are preserved in remote tissue.     

组织多普勒成像在急性心肌缺血心功能异常中的实验研究

目的 运用组织多普勒成像（TDI）技术对急性心肌缺血区域和二尖瓣环侧壁处的运动速度、移动振幅进行检测,探讨TDI在急性心肌缺血、心肌梗死中的应用价值。方法 10只开胸猪结扎左冠状动脉前降支（LAD）,通过TDI技术速度模式检测缺血区域和心尖四腔观二尖瓣环侧壁处的色泽变化及收缩、舒张期运动速度（VS,VE,VA）、移动振幅（CD,MDe,MDa）、等容收缩期时间,并与基础状态对照分析。结果 LAD结扎后,缺血区域和二尖瓣环处色泽暗淡,局部心肌色彩缺失,结扎15s时收缩期、舒张早期运动速度、移动振幅显著降低,等容收缩期时间延长。结论 TDI技术能准确反映血梗死区域运动异常,精确测定局部收缩、舒张期运动速度、移动振幅,尤其二尖瓣环处的运动能反映整体心肌的运动,为临床早期评价局部心肌缺血及心功能异常提供了一种无创性的检查手段。     

Left ventricular reverse remodeling in dilated cardiomyopathy- maintained subclinical myocardial systolic and diastolic dysfunction

In idiopathic dilated cardiomyopathy (DCM), myocardial deformational parameters and their relationships remain incompletely characterized. We measured those parameters in patients with DCM, during left ventricular reverse remodeling (LVRR). Prospective study of 50 DCM patients (in sinus rhythm), with left ventricular ejection fraction (EF) <40%. LVRR was defined as an increase of ten units of EF and decrease of diastolic left ventricular diameter (LVDD) in the absence of resynchronization therapy. Performed morphological analysis, myocardial performance quantification (LV and RV Tei indexes) and LV averaged peak systolic longitudinal strain (SSR long) and circumferential strain (SSR circ). At baseline, mean EF was 25.4?±?9.8%, LVDD was 62.4?±?7.4 mm, LVDD/BSA of 34.2?±?4.5 mm/m² and 34% had MR grade >II/IV. LVRR occurred in 34% of patients within 17.6?±?15.6 months and was associated with a reduced rate of death or heart failure hospitalization (5.9% vs. 33.3; p?=?0.03). Patients with LVRR had a final EF of 48.9?±?7.9% (Δ LV EF of 22.4%) and there was a significant decrease (p?<?0.05) in: LVDD/BSA, LV systolic diameter/BSA, LV diastolic volume, LV systolic volume, LV mass; an increase (p?<?0.05) in sphericity index. However, measures of diastolic function (LA volume/BSA, e′velocity and’ E/e′ratio), final LV and RV Tei indexes were not significantly different from baseline. Additionally, final SSR circ and SSR long values were not different from basal. Patients who recovered EF >50% (n?=?10), SSR circ and SSR long were inferior to normal. Improvement in EF occurred in one-third of DCM pts and was associated with a decrease of major cardiac events. There was an improvement of diastolic and systolic volumes and in sphericity index, confirming truly LV reverse reshaping. However, myocardial performance indexes, SSR long and SSR circ in reverse-remodeled DCM were still abnormal, suggesting a maintained myocardial systolic and diastolic dysfunction.     

Transesophageal dobutamine stress echocardiography with tissue Doppler imaging for detection and assessment of coronary artery disease.

BACKGROUND: Transesophageal dobutamine stress echocardiography (T-DSE) has been shown to be a sensitive and specific technique for the detection of myocardial ischemia. A major limitation of echocardiographic study interpretation, however, is the subjective visual analysis of endocardial motion and wall thickening, which is only semiquantitative. METHODS: To analyze whether T-DSE with the use or tissue Doppler imaging (TDI) during graded dobutamine infusion may be useful to detect and quantify stress-induced myocardial ischemia by changes in myocardial velocities, 70 patients undergoing coronary arteriography were studied with T-DSE and TDI. Midesophageal and transgastric short- and long-axis images were obtained at each level of dobutamine infusion. T-DSE was successful in 67 patients (96%). Baseline resting pulsed and color peak systolic (S) and early diastolic (E) velocities of the anterior, septal, lateral, and inferior walls were examined. RESULTS: Pulsed and color TDI correlated well at rest and after stress. Fifteen patients had a normal response to dobutamine, and 52 patients had inducible ischemia by two-dimensional criteria. In the normal group, there was a significant dose-dependent increase in S and E velocities. Compared with those in the normal group, patients with coronary artery disease (CAD) had lower resting S and E velocities and blunted S wave increase or E wave decrease during DSE. CONCLUSIONS: T-DSE with TDI is a feasible and accurate test for the quantitative assessment of patients with CAD who have impaired augmentation of systolic and diastolic myocardial velocities during dobutamine infusion.     

Effect of an acute increase in afterload on left ventricular regional wall motion velocity in healthy subjects.

We recorded left ventricular (LV) wall motion velocities before and after angiotensin II infusion by pulsed tissue Doppler imaging in 20 healthy subjects, and evaluated the responses of systolic and diastolic LV function along the long and short axes during an acute increase in afterload. Angiotensin II was administered intravenously to obtain a 30% increase in mean blood pressure. After angiotensin II infusion, LV end-systolic dimension and end-systolic circumferential wall stress increased significantly, and the percentage of LV fractional shortening decreased significantly. Peak first systolic LV wall motion velocity (Sw1 ) along the long axis decreased markedly compared with that along the short axis, and peak second systolic LV wall motion velocity (Sw2 ) along the short axis decreased significantly compared with that along the long axis. Early diastolic LV wall motion velocities along both the long and short axes decreased significantly, whereas atrial systolic LV wall motion velocity did not change. In conclusion, an acute increase in afterload caused a significant decrease in longitudinal fiber shortening during the isovolumic contraction phase (Sw1 along the long axis), circumferential fiber shortening during the ejection phase (Sw2 along the short axis), and LV relaxation during early diastole (early diastolic LV wall motion velocities along both axes) in healthy subjects. Pulsed tissue Doppler imaging may be useful for detecting the effect of various loading conditions on LV wall motion velocities along the long and short axes.     

心肌运动速度和应变率评价不同程度心肌缺血

目的应用定量组织速度成像(QTVI)技术检测犬不同程度急性心肌缺血前后左室前壁心肌运动速度和应变率(SR)的变化，探寻一种能定量、敏感、无创性地评价左室局部收缩及舒张功能的新方法。方法将9只开胸犬冠状动脉左前降支(LAD)血流减少造成中度、重度心肌缺血模型，取左室乳头肌水平短轴观，以QTVI分别检测不同程度缺血时左室前壁心内膜下心肌和心外膜下心肌收缩期峰值运动速度(Vsendo、Vsepi)、舒张早期峰值运动速度(Veendo、Veepi)，并计算出收缩期SR(SRs)和舒张早期SR(SRe)。结果基础状态下，心内膜下心肌速度高于心外膜下心肌速度。缺血导致左室前壁Vsendo、Veendo、Veepi和SRe均显著下降，尽管Vsepi降低不明显，但SRs降低显著。结论心肌运动速度和应变率能敏感地评价不同程度实验性心肌缺血，比常规的方法(运动幅度和室壁增厚率)更敏感。     

实验性冠状动脉痉挛的组织多普勒成像研究

目的　以麦角新碱诱发实验兔的冠状动脉 (冠脉 )痉挛引起急性心肌缺血的组织多普勒研究。方法　应用组织多普勒成像脉冲技术检测 35只冠脉痉挛引起急性心肌缺血兔的左室心尖部和前壁基底段、中段和心尖段的心肌运动 ,测量收缩期、舒张早期和舒张晚期运动峰值速度及时间速度积分 ,并与痉挛前对照分析。结果　冠脉痉挛后心尖部及前壁中段、心尖段的收缩波、舒张早期波峰值速度及时间速度积分明显低于痉挛前(P<0 .0 1)。舒张晚期波及前壁基底段各测值两组相差不显著 (P>0 .0 5 )。结论　组织多普勒成像脉冲技术能够准确测定心肌局部收缩和舒张运动速度 ,对冠脉痉挛引起的心肌缺血检测提供一种定量的方法。     

应变及应变率成像评估心肌桥患者局部心肌缺血的价值

目的探讨定量组织速度成像和应变及应变率评估冠状动脉心肌桥引起局部心肌缺血的临床价值。方法冠状动脉前降支心肌桥患者47例(心肌桥组)与冠状动脉正常者40例(对照组),测量前降支支配区域9个节段的收缩期峰值速度、峰值应变及应变率、舒张早、晚期峰值速度、舒张早、晚期峰值应变及相应的应变率。结果与对照组比较,心肌桥组前间隔各节段、前壁基底段及中间段、后间隔中间段收缩期峰值速度及峰值应变率明显减低(P<0.05);前间隔基底段和中间段舒张早期、晚期峰值速度及舒张早期峰值应变率明显减低(P<0.05);前壁基底段、前间隔各节段收缩期峰值应变,前壁、前间隔舒张晚期峰值应变明显减低、侧壁心尖段明显升高(P<0.05)。结论定量组织速度成像和应变及应变率可定量检测冠状动脉心肌桥引起的心肌缺血。     

Evaluation of a novel index by tissue Doppler imaging in patients with advanced heart failure: relation to functional class and prognosis

Background: Despite the ability of tissue Doppler imaging (TDI) to detect left ventricular (LV) systolic and diastolic myocardial functions in patients with heart failure, the added value of TDI to clinical variables and conventional echocardiography in predicting the symptoms and outcome of advanced heart failure has not been clearly defined. Methods and results: Two hundred and thirty adult patients diagnosed with congestive heart failure were assigned to study groups based on the New York Heart Association functional classes. Pulsed‐wave TDI (PWTDI), including average of peak systolic (Sm), early (Em) and late diastolic (Am) velocities from six mitral annular sites was evaluated. PWTDI was also calculated to create a combined index (EAS index) of diastolic and systolic performances. All patients were followed up for cardiac‐related death and hospitalisation as a result of heart failure. Patients with functional class III–IV had a significantly higher EAS index (0.21 ± 0.19 vs. 0.13 ± 0.08, p < 0.05) than those with class I–II and the control (0.10 ± 0.04, p < 0.05). Except for Sm and Em, all conventional echocardiographic Doppler parameters and TDI variables significantly correlated with functional class. Moreover, according to multiple stepwise analysis, EAS index and percentage of chronic renal insufficiency (CRF) were the only two independent predictors of functional class (EAS index, p = 0.006; CRF, p = 0.019). During follow‐up (median, 30 months), 93 participants had cardiac events. EAS index, LV mass index and CRF were significant predictors of cardiac mortality and hospitalisation [EAS index, hazard ratio (HR) 4.962, p = 0.006; LV mass index, HR 1.007, p = 0.003; CRF, HR 1.616, p = 0.040]. Conclusions: The EAS index, which reflects systolic and diastolic performances, is a highly effective means of differentiating between patients with functional class I–II and those with III–IV. The index also correlates with cardiac mortality and hospitalisation for worsening heart failure, thus providing additional value to conventional echocardiographic measures.     

定量组织速度成像技术评价3-AB对急性心肌梗死大鼠左室收缩功能的影响

目的应用定量组织速度成像技术（QTVI）评价3-氨基苯甲酰胺（3-AB）对大鼠急性心肌梗死后左室收缩功能的影响。方法将冠状动脉左前降支起始部结扎的雌性Wistar大鼠随机分为3-AB干预组（n=14）和空白对照组（n=12）。另设同期假手术大鼠（n=10）作为正常对照。3-AB治疗2周后行超声心动图检查。结果与假手术组相比，对照组的左室前壁舒张末期厚度（LVAWd）明显变薄（P〈0．01），左室舒张末期内径（LVDd）、舒张末期容积（EDV）显著增加（P〈0．01）；左室短轴缩短率（FS）、射血分数（LVEF）显著降低（P〈0．01）；心尖四腔左室侧壁及后间隔二尖瓣环、左室长轴观前间隔及后壁中间段收缩期峰值速度显著下降（P〈0．01）；干预组与对照组相比以上各指标均有明显的改善（P〈0．05）。结论定量组织速度成像技术结合常规高频超声心动图能无创定量评价3-AB有效抑制大鼠急性心肌梗死后左室重构及改善左室收缩功能的作用。     

多普勒组织成像技术评价肥厚型心肌病患者心室运动的协调性

目的应用多普勒组织成像技术（doppler tissue imaging,DTI）评价肥厚型心肌病（hypertrophic cardiomy-opathy,HCM）患者心室运动的协调性。方法对38例HCM患者和38例对照组进行常规超声心动图检查,分别测量左室内径、左室壁厚度、左室射血分数（LVEF）、二尖瓣舒张早期血流速度峰值（E）、二尖瓣舒张晚期血流速度峰值（A）、二尖瓣峰值速度比值（E/A）、等容舒张期（IVRT）、心室间机械运动延迟（IVMD）,转换DTI速度模式,分别测量二尖瓣环室间隔、侧壁、下壁及三尖瓣环右室侧壁的心肌收缩期峰值速度（Sm）、舒张早期峰值速度（Em）、舒张晚期峰值速度（Am）、Em/Am、Q-Sm（Q波起始到Sm起始的时间间期）,计算心室内收缩延迟时间（intra-V-Del）和心室间收缩延迟时间（inter-V-Del）。结果HCM组的IVSTI、VST/PWTI、VRTI、VMD、LVDd、A、E、E/A与对照组比较差异均有统计学意义（P〈0.05,P〈0.01）。HCM组室间隔、侧壁、下壁、右室侧壁节段Sm、Q-smi、ntra-V-Del、inter-V-Del、Em、Em/Am与对照组比较差异均有统计学意义（P〈0.05,P〈0.01）。结论HCM患者存在心室收缩功能下降和心室收缩运动协调障碍,DTI对HCM患者治疗效果和预测预后具有重要的临床指导意义。     

Tissue Doppler imaging (TDI) for on-line detection of regional early diastolic ventricular asynchrony in patients with coronary artery disease

Diastolic filling of the left ventricle is often impaired in patients with coronary artery disease (CAD) in the absence of systolic wall motion abnormalities or previous myocardial infarction. The current study was designed to assess the ability of tissue Doppler imaging (TDI) for on-line detection of regional diastolic wall motion abnormalities to identify CAD in patients with preserved systolic function. 20 normal subjects (age 51 ± 13?years) and 17 CAD patients with normal systolic function and ≥70% luminal narrowing of the LAD (age 56 ± 11?years) were included. Coronary anatomy was unknown to the echocardiographer. In the parasternal short axis and the apical 4-chamber-view, peak tissue velocities of the anterior/inferior and the midseptal/midlateral LV segments during rapid ejection (RE), isovolumic relaxation (IR), rapid filling (RF) and atrial contraction (AC) were analyzed by color-M-Mode-TDI. In the apical view, in 13 of 35 (37%) patients with adequate recordings, myocardial asynchrony was detected during IR: while the septum was moving inwards (red color-coding), the lateral wall was moving outwards (blue/green coding). In the remaining 22 patients (63%) a slow, synchronous outward motion of septum and lateral wall with homogeneous color-coding (blue/green) was seen. Unblinding of the coronary status revealed a critical LAD stenosis in all 13 patients (100%) with myocardial asynchrony. Analysis of midseptal peak velocities during IR revealed positive velocities (1.22 ± 1.64?cm/s) in CAD patients and negative velocities (?1.39 ± 0.81?cm/s) in normal subjects. Thus, TD1 allowed for the on-line detection of early diastolic asynchrony in 13 of 16 (82%) patients with critical LAD-narrowing. Due to the rapid assessment of regional wall motion abnormalities, TDI might help to identify CAD in patients with normal systolic function.     

Reproducibility and observer variability of tissue phase mapping for the quantification of regional myocardial velocities

To systematically investigate the reproducibility of global and segmental left ventricular (LV) velocities derived from tissue phase mapping (TPM). Breath held and ECG synchronized TPM data (spatial/temporal resolution?=?2?×?2 mm²/20.8 ms) were acquired in 18 healthy volunteers. To analyze scan–rescan variability, TPM was repeated in all subjects during a second visit separated by 16?±?5 days. Data analysis included LV segmentation, and quantification of global and regional (AHA 16-segment modal) metrics of LV function [velocity–time curves, systolic and diastolic peak and time-to-peak (TTP) velocities] for radial (Vr), long-axis (Vz) and circumferential (VΦ) LV velocities. Mean velocity time curves in basal, mid-ventricular, and apical locations showed highly similar LV motion patterns for all three velocity components (Vr, VΦ, Vz) for scan and rescan. No significant differences for both systolic and diastolic peak and TTP myocardial velocities were observed. Segmental analysis revealed similar regional peak Vr and Vz during both systole and diastole except for three LV segments (p?=?0.045, p?=?0.033, and p?=?0.009). Excellent (p?<?0.001) correlations between scans and rescan for peak Vr (R²?=?0.92), peak Vz (R²?=?0.90), radial TTP (R²?=?0.91) and long-axis TTP (R²?=?0.88) confirmed good agreement. Bland–Altman analysis demonstrated excellent intra-observer and good inter-observer analysis agreement but increased variability for long axis peak velocities. TPM based analysis of global and regional myocardial velocities can be performed with good reproducibility. Robustness of regional quantification of long-axis velocities was limited but spatial velocity distributions across the LV could reliably be replicated.     

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.