Subendocardial motion in hypertrophic cardiomyopathy: assessment from long- and short-axis views by pulsed tissue Doppler imaging.

BACKGROUND: Tissue Doppler imaging (TDI) is a recently developed technique that allows the instantaneous measurement of intrinsic regional myocardial motion velocity. Pulsed TDI is capable of separately assessing left ventricular (LV) regional motion velocity caused by circumferential and longitudinal fiber contraction. This particular feature of function is still controversial in patients with hypertrophic cardiomyopathy (HC). METHODS: To better characterize intrinsic circumferential and longitudinal LV systolic myocardial function in HC, we used pulsed TDI to measure short- and long-axis LV motion velocities, respectively. The subendocardial motion velocity patterns at the middle of the LV posterior wall (PW) and ventricular septum (IVS) in LV parasternal and apical long-axis views were recorded by pulsed TDI in 19 patients with nonobstructive HC and in 21 normal controls (NC). RESULTS: Peak short- and long-axis systolic subendocardial velocities in both the LV PW and IVS were significantly smaller in the HC group than in the NC group, and the time to peak velocity was significantly delayed. Furthermore, peak PW systolic velocity was significantly greater along the long axis than along the short axis in the NC group (8.8 +/- 1.5 cm/s vs 8.2 +/- 1.4 cm/s, P <.05), whereas the opposite was observed in the HC group (6.1 +/- 1.2 cm/s vs 7.5 +/- 1.0 cm/s, P <.0001). No significant differences were found in either group between the long- and short-axis IVS velocities (HC: 5.9 +/- 1.4 cm/s vs 5.5 +/- 1.3 cm/s; NC: 7.8 +/- 1.3 cm/s vs 7.9 +/- 1.6 cm/s). CONCLUSIONS: By using the capability of pulsed TDI for the evaluation of intrinsic myocardial velocity instantaneously in a specific region and direction, we found impairment of LV myocardial systolic function in patients with HC not only in the hypertrophied IVS but also in the nonhypertrophied LV PW. We also found a greater decrease in LV PW velocities along the long axis than the short axis, suggesting greater impairment of long-axis contraction in patients with HC. Because our HC patients did not appear to have excessive intracavitary pressure, these results suggest that the relatively normal-appearing PW is directly affected by the HC pathologic process.     

Development of a fully quantitative approach to the interpretation of stress echocardiography using radial and longitudinal myocardial velocities.

BACKGROUND: Tissue Doppler may be used to quantify regional left ventricular function but is limited by segmental variation of longitudinal velocity from base to apex and free to septal walls. We sought to overcome this by developing a composite of longitudinal and radial velocities. METHODS AND RESULTS: We examined 82 unselected patients undergoing a standard dobutamine echocardiogram. Longitudinal velocity was obtained in the basal and mid segments of each wall using tissue Doppler in the apical views. Radial velocities were derived in the same segments using an automated border detection system and centerline method with regional chords grouped according to segment location and temporally averaged. In 25 patients at low probability of coronary disease, the pattern of regional variation in longitudinal velocity (higher in the septum) was the opposite of radial velocity (higher in the free wall) and the combination was homogeneous. In 57 patients undergoing angiography, velocity in abnormal segments was less than normal segments using longitudinal (6.0 +/- 3.6 vs 9.0 +/- 2.2 cm/s, P =.01) and radial velocity (6.0 +/- 4.0 vs 8.0 +/- 3.9 cm/s, P =.02). However, the composite velocity permitted better separation of abnormal and normal segments (13.3 +/- 5.6 vs 17.5 +/- 4.2 cm/s, P =.001). There was no significant difference between the accuracy of this quantitative approach and expert visual wall motion analysis (81% vs 84%, P =.56). CONCLUSION: Regional variation of uni-dimensional myocardial velocities necessitates site-specific normal ranges, probably because of different fiber directions. Combined analysis of longitudinal and radial velocities allows the derivation of a composite velocity, which is homogeneous in all segments and may allow better separation of normal and abnormal myocardium.     

Acute regional myocardial ischemia identified by 2-dimensional multiregion tissue Doppler imaging technique.

BACKGROUND AND OBJECTIVE: Tissue Doppler echocardiography (TDE) is a promising method for the assessment of regional myocardial function, but pulsed TDE does not provide quantitative data from multiple regions simultaneously. This feature is important for the objective assessment of regional differences in myocardial function. In the present study, we investigated a new off-line TDE method that provides quantitative pulsed velocity data from an unlimited number of regions selected within a 2-dimensional (2D) image. The goal of the study was to determine the ability of this new approach to quantify regional myocardial function during acute myocardial ischemia induced by balloon angioplasty. METHODS: Twenty-two patients undergoing angioplasty of the left anterior descending coronary artery (LAD) were studied. Left ventricular longitudinal wall motion was assessed by 2D TDE from the apical 4-chamber view before, during, and after angioplasty. Images were sampled at a rate of 69 +/- 15 frames/s, and the off-line analysis allowed simultaneous measurement of velocities in multiple myocardial segments. RESULTS: There were 3 major alterations in the systolic velocity pattern during LAD occlusion. Peak early systolic velocities along the apical septum were significantly reduced during LAD occlusion (2.8 +/- 1.2 cm/s to 0.6 +/- 1.7 cm/s, P <.001). Myocardial velocities in mid systole suggested paradoxical wall motion (1.0 +/- 1.2 cm/s to -0.8 +/- 0.9 cm/s, P <.001). When comparing the ischemic regions of the left ventricle with the nonischemic regions, each patient demonstrated lower myocardial systolic velocities in the ischemic region. Furthermore, during early diastole, the wall motion of the ischemic segments showed a postsystolic contraction pattern with velocities changing from -0.9 +/- 1.0 cm/s to 1.9 +/- 1.3 cm/s (P <.001). CONCLUSION: This new 2D TDE approach is able to quantify detailed myocardial velocity profiles from multiple regions simultaneously. Single-beat comparisons of ischemic and nonischemic regions might enhance the sensitivity for diagnosing ischemic heart disease. Reversed systolic wall motion during midsystole and marked positive velocity during early diastole might be new and important markers of myocardial wall ischemia.     

Radial versus longitudinal myocardial deformation from gray-scale echocardiography

The objectives of this work are to evaluate a novel non-Doppler-based echocardiographic method that makes it possible to simultaneously obtain the radial and longitudinal components of myocardial velocity (V) and strain (S), and to assess whether left ventricular fiber architecture affects the net function of the myocardium. Previous reports state that differences in the estimation of regional function between septum and lateral walls can be related to the anatomic disposition of myocardial fibers. In this work we measure and compare in 21 healthy volunteers longitudinal and radial peak systolic velocity V (V(long), V(rad): cm/s), peak systolic strain S (S(long), S(rad): %) and time-to-peak S and V (T-Smax, T-V(max): ms) at the midsegments of the septal and lateral walls. Results show that V was higher, both in the radial and longitudinal components, in the lateral wall than in the septum (V(rad): 4.77 +/- 0.26 cm/s vs. 3.77 +/- 0.20 cm/s, p = 0.007; V(long): 5.60 +/- 0.48 cm/s vs. 4.13 +/- 0.11 cm/s, p = 0.01). Radial strain was higher in the septum (S(rad): 28.63 +/- 2.25% vs. 22.54 +/- 1.5%, p = 0.015), and longitudinal strain, in the lateral wall (S(long): -25.89 +/- 1.43% vs. -22.20 +/- 0.87%, p = 0.02). There was a significant delay in longitudinal T-Smax between the lateral and septal medial segments (mean: 14.5 ms; CI 95%: 0.3-28.6 ms; p = 0.04), with no difference in radial T-Smax (277.1 +/- 8.6 ms vs. 277.2 +/- 12.4 ms, p = 0.93). The assessment of regional myocardial function by this new method enables the simultaneous analysis of its radial and longitudinal components. These measurements correlate well with previous anatomical knowledge of the architecture of myocardial fibers, emphasizing its functional significance in regional myocardial function analysis.     

Assessment of left ventricular systolic and diastolic function by Doppler tissue imaging in patients with preinfarction angina.

BACKGROUND: The aim of this study was assessment of left ventricular (LV) systolic and diastolic function by pulsed wave Doppler tissue imaging (DTI) in patients with or without preinfarction angina in acute myocardial infarction. METHODS: We prospectively evaluated 31 consecutive patients (4 women, 27 men; age 58 +/- 10 years) with a first acute myocardial infarction. LV systolic and diastolic function was assessed by classic methods and DTI on the third day during acute myocardial infarction. Patients were divided into 2 groups according to the presence (group 1; n = 10) or absence (group 2; n = 21) of preinfarction angina. Mitral inflow velocities and early diastolic mitral annular velocity (Em), late diastolic mitral annular velocity (Am), peak systolic mitral annular velocity, Em/Am, the ratio of early diastolic mitral inflow velocity (E) to Em, and myocardial performance index were calculated by DTI. RESULTS: Group 1 had significantly higher Em and Em/Am than group 2 (11.3 +/- 3.34 cm/s vs 7.4 +/- 2.07 cm/s, P <.0001; 1.01 +/- 0.38 cm/s vs 0.6 +/- 0.2 cm/s, P =.001, respectively). The E/Em ratio and myocardial performance index were significantly lower in group 1 than in group 2 (5.1 +/- 2.92 vs 8.10 +/- 3.15, P=.018; 0.49 +/- 0.15 vs 0.65 +/- 0.24, P =.042, respectively). Wall-motion score index was lower in those with preinfarction angina than in those without (1.6 +/- 0.36 vs 1.9 +/- 0.39; P =.04, respectively). Peak systolic mitral annular velocity and Am were not statistically different between groups (9.4 +/- 1.84 vs 8.3 +/- 2.03, P =.172; 11.7 +/- 3.07 vs 12.1 +/- 3.34, P =.72, respectively). There were no significant differences between the 2 groups regarding transmitral E velocity, atrial contraction mitral inflow velocity (A), E/A ratio, isovolumetric relaxation time, and deceleration time of the mitral E wave (P =.91, P =.08, P =.58, P =.81, and P =.71, respectively). CONCLUSION: LV diastolic function was better in patients with preinfarction angina than in patients without. This condition could not be detected by conventional mitral inflow Doppler velocities, but could be detected by DTI. This preliminary evidence shows that DTI is better than conventional mitral Doppler indices in the assessment of a favorable LV diastolic function in patients with preinfarction angina.     

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.     

Reversal of intraventricular flow propagation during isovolumic relaxation: A marker of anterior wall dysfunction.

BACKGROUND: Myocardial infarction induces left ventricular (LV) wall motion abnormalities during isovolumic relaxation (IVR) and may potentially alter intraventricular flow during this period. This study evaluated whether 2-dimensional color Doppler measurements of intraventricular flow during IVR were able to identify LV dysfunction caused by coronary artery disease. METHODS: Patients with single-vessel coronary artery disease and posterior wall infarction (21 patients) or anterior wall infarction (27 patients) were included. Eighteen healthy persons served as a control group. LV function was examined by 2-dimensional echocardiography, 2-dimensional color Doppler, and pulsed Doppler techniques. RESULTS: All normal persons (23.6 +/- 10.9 cm/s) and patients with posterior infarction (19.6 +/- 9.3 cm/s) had flow propagation towards LV apex during IVR. Patients with anterior wall infarction had reversed flow direction (-12.2 +/- 8.7 cm/s, P <.001). The echocardiographic wall motion score index of the 4 apical segments correlated well with flow velocities (r = -0.78, P <.001). CONCLUSION: Reversed flow propagation during IVR may become a sensitive clinical marker of regional ischemia.     

Association of severe coronary stenosis with subclinical left ventricular dysfunction in the absence of infarction.

BACKGROUND: Regional left ventricular (LV) dysfunction may occur in patients with coronary artery disease (CAD) in the absence of infarction, but the causes of this phenomenon are unclear. We sought to identify whether changes in regional LV function were related to stenosis severity, using sensitive new ultrasound markers of function. METHODS: We studied 67 individuals with no history of infarction and with normal LV systolic function: 49 patients with CAD and 18 control subjects without CAD. All patients underwent color Doppler tissue imaging, integrated backscatter (IB), anatomic M-mode echocardiography, and strain rate imaging to detect changes in structure and function. Peak early and late diastolic myocardial velocity, cyclic variation of IB, wall thickness, and percent wall thickening were measured in each basal and mid segment. Strain rate and peak systolic strain were calculated in each wall. CAD was defined as >or=50% diameter stenosis. Normokinetic segments (n = 354) subtended by CAD were divided according to stenosis severity into 3 groups: group 1 (subtended by 50%-69% stenosis); group 2 (subtended by 70%-98% stenosis); and group 3 (subtended by >or=99% stenosis). Each parameter in each group was compared with that in 216 segments from control subjects. RESULTS: Segments subtended by significant CAD showed lower peak early and late diastolic myocardial velocity compared with control segments. Group 3 showed significantly lower myocardial velocities than group 2 for both peak early (4.8 +/- 1.8 vs 6.0 +/- 2.0 cm/s, P <.05) and late (4.5 +/- 2.1 vs 5.6 +/- 2.1 cm/s, P <.05) diastolic myocardial velocity. Group 3 also showed a significantly lower cyclic variation IB than did control segments (6.7 +/- 2.3 vs 7.9 +/- 2.6 dB, P <.05), but there was no difference in calibrated IB, wall thickness, strain parameters, or percent wall thickening. These differences were not attributable to the distribution of segments for patients with severe CAD, nor were they explained on the basis of collaterals. CONCLUSION: Although the absolute values show overlap between groups, the results of this study indicate that subtle changes of regional LV function may occur in the absence of infarction, in association with severe coronary stenoses.     

Doppler tissue echocardiographic features of cardiac amyloidosis.

The purpose of the study was to assess whether quantification of myocardial involvement by Doppler tissue echocardiography (DTE) enhances the accuracy of echocardiographic characterization of cardiac amyloidosis (CA). A group of 36 patients with CA (mean age 58 +/- 13 years; 22 male) and 40 age-matched control patients were studied. Patients with CA were divided into CA-1 subgroup with nonrestrictive (n = 22) and CA-2 with restrictive left ventricular (LV) filling pattern (n = 14). Peak lateral and medial mitral annulus velocities by pulsed wave DTE were measured in systole, early diastole, and late diastole. Using color M-mode DTE of the LV posterior wall, mean myocardial velocities (MMV) and myocardial velocity gradient (MVG) were measured during ventricular ejection, early and late isovolumic relaxation (IVR), rapid ventricular filling, and atrial contraction. In both CA-1 and CA-2 groups, mitral annulus velocities, MMV, and all MVG were lower than those measured in control patients, with the exception of peak late diastolic annulus velocities at lateral side and MMV in atrial contraction. MVGs in both early IVR and rapid ventricular filling were lower in the CA-1 as compared with the CA-2 group. Late IVR-MVG was negative in control patients and positive in patients with CA indicating a faster movement of the subendocardium rather than the subepicardium during late IVR in patients with CA (0.88 +/- 0.50 s(-1) vs -0.40 +/- 1.59 s(-1); P <.001). The following parameters: peak early diastolic annulus velocities at lateral side < or = -12 cm/s, peak early diastolic annulus velocities at medial side < or = -10 cm/s, early IVR-MMV < or = -2.5 cm/s, early IVR-MVG < or = -0.7 s(-1), and late IVR-MVG > or = 0.5 s(-1) differentiated patients with CA from control patients with an overall accuracy of 0.82, 0.83, 0.81, 0.87, and 0.81, respectively. In patients with CA, reduction in early IVR-MMV was independent of patients' age and LV mass. DTE indices proved helpful in differentiating patients with CA from control patients including those patients with CA who had borderline conventional echocardiographic features and nonrestrictive LV filling pattern.     

定量组织速度成像对心梗病人左室心肌局域舒张功能的分析

目的探索冠心病人左室等容舒张期和快速充盈期局部心肌的舒张运动特点及其临床意义。方法以60帧/秒以上的高帧频对18例心肌梗死病人（MI组）和20例正常人（对照组）的左室心肌进行QTVI检查。获取左室各节段心肌长轴方向的同步运动曲线,测量其等容舒张期、快速充盈期、心房收缩期局部心肌的运动速度V     

Clinical relevancy of the myocardial velocity gradient: limitations of a binary response

BACKGROUND: Doppler tissue echocardiographic myocardial velocity gradient (MVG) overcomes translational or tethered motion effects. Diagnostic applications rely on MVG numeric value, an instantaneous value calculated at peak endocardial velocity. Our aim was to test the clinical relevancy of MVG for patients with dilated cardiomyopathy (CM) at rest. Efficiency of MVG, as a marker of the underlying mechanism, ischemic or nonischemic, was compared with that of mean velocities averaged over a cycle. METHODS: Peak and mean velocities were measured and MVG calculated during ejection, and early and late diastole, in the endocardium and epicardium on color M-mode Doppler tissue echocardiographic parasternal recordings of the posterior wall, simultaneously imaged with the septum. The population consisted of 34 patients with similar clinical presentation (left ventricular ejection fraction < 40%, left ventricular end-diastolic diameter > 6 cm, and proven ischemic [14] or nonischemic [20] dilated CM) and 16 control subjects. RESULTS: Doppler tissue echocardiography data significantly differed between control subjects and all patients with CM. Between patients, the only significant differences were found at the posterior wall for mean velocities at the epicardium in systole (9 +/- 4 mm/s for ischemic vs 14 +/- 5 mm/s for nonischemic, P =.002), and at both layers in early diastole (endocardium, 14 +/- 9 vs 29 +/- 12 mm/s, P =.0004; epicardium, 12 +/- 4 vs 22 +/- 11 mm/s, P =.002; ischemic vs nonischemic CM, respectively). CONCLUSION: Specific features of CM were characterized by myocardial velocity changes studied layer by layer throughout a phase. The binary response of transient peak MVG could not reach this goal.     

Impact of flow level on coronary flow velocity pattern. A doppler flow study in patients with first acute myocardial infarction

Analysis of coronary flow velocity pattern has been used to assess microvascular function post acute myocardial infarction (AMI). This study sought to analyze whether the flow level has an impact on parameters of coronary flow velocity pattern. Parameters of coronary flow velocity pattern were determined at baseline and during increased flow due to maximal hyperemia induced by adenosine in 25 patients after PTCA for first AMI using Doppler flow wires. Patients were divided into those with depressed (global wall motion index (GWMI) > or = 1.5; n = 14) and those with preserved (GWMI < 1.5; n = 11) left ventricular (LV) function at 4 weeks. Coronary flow velocity pattern at rest was different between patients with depressed and patients with preserved LV function at follow-up. A difference in flow pattern between the groups remained at increased flow level. However, increase of flow altered parameters of flow pattern. Diastolic deceleration rate (DSR) increased for patients with preserved LV function (53.7+/-25.6 at baseline vs. 67.0+/-29.8 cm/s2 with adenosine) and depressed LV function (95.3+/-58.6 vs. 110.7+/-61.4 cm/s2, respectively, p = 0.0012). Induction of hyperemia resulted also in increased systolic and diastolic peak flow velocity and diastolic deceleration time (DDT). Higher flow had no impact on early systolic retrograde flow, systolic flow duration and diastolic-systolic velocity ratio (DSVR). The coronary flow velocity pattern allows prediction of LV function at 4 weeks after AMI. However, it should be considered that some parameters of the flow velocity pattern are affected by the coronary flow level.     

Heart deformation analysis: measuring regional myocardial velocity with MR imaging

The aim of the present study was to test the hypothesis that heart deformation analysis (HDA) may serve as an alternative for the quantification of regional myocardial velocity. Nineteen healthy volunteers (14 male and 5 female) without documented cardiovascular diseases were recruited following the approval of the institutional review board (IRB). For each participant, cine images (at base, mid and apex levels of the left ventricle [LV]) and tissue phase mapping (TPM, at same short-axis slices of the LV) were acquired within a single magnetic resonance (MR) scan. Regional myocardial velocities in radial and circumferential directions acquired with HDA (Vrr and Vcc) and TPM (Vr and VФ) were measured during the cardiac cycle. HDA required shorter processing time compared to TPM (2.3?±?1.1 min/case vs. 9.5?±?3.7 min/case, p?<?0.001). Moderate to good correlations between velocity components measured with HDA and TPM could be found on multiple myocardial segments (r?=?0.460–0.774) and slices (r?=?0.409–0.814) with statistical significance (p?<?0.05). However, significant biases of velocity measures at regional myocardial areas between HDA and TPM were also noticed. By providing comparable velocity measures as TPM does, HDA may serve as an alternative for measuring regional myocardial velocity with a faster image processing procedure.     

速度向量成像技术定量评价正常人左心室扭转运动

目的 采用速度向量成像技术研究正常人的左心室心内膜和心外膜扭转运动特点.方法 对10例正常成年人行常规超声心动图和二维斑点显像检查.斑点追踪切面包括基底切面(二尖瓣水平左心室短轴)和心尖切面(心尖水平左心室短轴),应用Siemens SyngoWorkPlace V 2.0 工作站进行后处理分析.结果 无论是心内膜或心外膜,左心室基底部收缩期旋转均为负值,舒张期旋转均为正值,心尖部则相反,收缩期心尖部旋转速度的绝对值显著高于基底部[心内膜:(150±62)°/s 对 (114±65)°/s;心外膜:(81±40)°/s和(55±28)°s,均 P<0.01)].无论是基底部或心尖部,收缩期心内膜旋转速度和旋转角度均显著高于心外膜[基底部:(-114±65)°/s对 (-55±28)°s,(-12±6)°对(-4±1)°;心尖部:(150±62)°/s对 (81±40)°/s,(10±4)°对 (6±2)°,均 P＜0.05)]°收缩期基底部和心尖部心内膜和心外膜平均旋转速度达峰时间[基底部(188±72)ms 对 (187±55)ms;心尖部(195±85)ms 对 (141±79)ms3、舒张期基底部和心尖部心内膜和心外膜平均旋转速度达峰时间[基底部(446±58)ms 对 (491±53)ms;心尖部(453±57)ms 对 (466±85)ms]及收缩期心内膜和心外膜平均旋转的达峰时间[基底部(296±69)ms对(292±63)ms;心尖部(251±67)ms 对 (295±66)ms]差异均无统计学意义(P＞0.05).结论 速度向量成像技术可无创伤性评价左心室环向旋转和扭转运动,正常人左心室具有特征性旋转运动.     

Diagnosis of viable myocardium using velocity data of Doppler myocardial imaging: comparison with positron emission tomography.

To test whether velocity data of Doppler myocardial imaging (DMI) at rest is useful for diagnosis of myocardial viability, 25 consecutive patients (age 64 +/- 10 years) with regional wall-motion abnormalities at the left anterior descending coronary artery territory and left ventricular dysfunction (ejection fraction: 31 +/- 7%) underwent both DMI at rest and positron emission tomography. The peak systolic velocity (Vpeak) and postsystolic thickening (PST) velocity were measured in myocardial segments of left anterior descending coronary artery territory from apical views. A total of 71 segments were classified by positron emission tomography as normal or viable in 38 (group A) and nonviable in 33 (group B). Although Vpeak did not show any difference between groups (1.81 +/- 1.77 vs 1.29 +/- 0.94 cm/s, P =.107), PST velocity was significantly higher in group A (2.48 +/- 1.68 vs 0.89 +/- 0.72 cm/s, P <.001). The sensitivity and specificity of PST velocity > 2.0 cm/s for diagnosis of viability were 61% (23/38) and 97% (32/33), respectively. In segments with PST velocity was < or =2.0 cm/s, Vpeak > 1.8 cm/s could discriminate group A from B with a sensitivity of 67% (10/15) and a specificity of 91% (29/32). The algorithm using both PST velocity and Vpeak of DMI showed sensitivity and specificity of 87% and 88%, respectively, for diagnosis of myocardial viability. Velocity data of DMI at rest provides robust information regarding viability in selected patients, and an advantage of this technique is that no stress testing is needed.     

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.     

The mechanism of emergence and clinical significance of apically directed intraventricular flow during isovolumic relaxation.

The mechanism of emergence and the clinical significance of apically directed intraventricular flow during isovolumic relaxation were investigated. The relation between the spatial distribution of the flow and left ventricular (LV) apical wall motion abnormality, as well as LV performance, was studied in 97 patients who underwent cardiac catheterization for evaluation of chest pain. According to the distribution of the flow, the patients were classified into the following 3 groups: flow observed in the whole area between the tip of the papillary muscle and the apex (spread flow) (n = 38), flow observed in the same area that did not fill the whole area (localized flow) (n = 15), and no apparent flow observed in the area (without flow) (n = 44). An absence of flow disclosed apical asynergy with a sensitivity of 97% and specificity of 87%. The time constant of LV relaxation was significantly shorter in patients with spread flow than in those without flow. A significant difference was also observed in end-systolic volume index (18.8 +/- 6.8 vs 30.9 +/- 7.7 vs 42.3 +/- 20.2 mL/m(2), spread flow < localized flow < without flow, P <.05) among the 3 groups. The propagation velocity of LV early diastolic filling flow was significantly greater in patients with spread flow (47.0 +/- 8.3 cm/s) than in those with localized flow (30.7 +/- 7.8 cm/s) or without flow (28.6 +/- 7.8 cm/s) (P <.001). These findings indicate that the greater magnitude of LV elastic recoil and the faster LV relaxation in patients without LV apical asynergy produce apically directed intraventricular flow during isovolumic relaxation, enhancing the speed of LV early diastolic filling. Apically directed intraventricular flow during isovolumic relaxation may play an important role as a mediator of better LV systolic performance and LV relaxation to LV early diastolic filling. Absence of apically directed intraventricular flow during isovolumic relaxation is a manifestation of LV apical asynergy and global LV dysfunction from end systole to early diastole.     

Clinical and echocardiographic predictors of left atrial appendage dysfunction in patients with mitral stenosis in sinus rhythm.

BACKGROUND: Mitral stenosis (MS) causes left atrial (LA) appendage (LAA) dysfunction resulting in reduced LAA flow velocities. Low LAA peak emptying velocity (PEV), determined by transesophageal echocardiography, is a risk for thrombus formation and systemic embolism. OBJECTIVE: We sought to investigate various clinical and echocardiographic predictors of low LAA blood flow velocities. METHODS: A total of 44 patients with newly diagnosed MS were classified into two groups on the basis of the presence of high (PEV > or = 46 cm/s) or low (PEV < 46 cm/s) LAA flow profile on Doppler transesophageal echocardiography. LAA flow velocities were measured to be 27.38 +/- 8.17 cm/s in patients with LAA dysfunction and 70.75 +/- 16.71 cm/s in high-flow profile (P <.0001). Simultaneous 12-lead electrocardiogram was used to measure P waves. RESULTS: P maximum, P dispersion, and LA diameter were significantly higher in patients with low LAA PEV (n = 32) than in those with high LAA PEV (111.87 +/- 16.93 vs 96.66 +/- 14.97, P =.0084; 73.12 +/- 20.7 vs 49.16 +/- 9.96, P <.0001; 46.06 +/- 4.384 vs 38.08 +/- 7.42 mm, P =.004; respectively). Patients with MS and low LAA blood flow had smaller mitral valve area compared with those with high LAA blood flow velocity (1.48 +/- 0.431 vs 1.85 +/- 0.442 cm(2), P =.02). Male sex, spontaneous echocontrast, and thrombus were more frequent in patients with low LAA PEV [7 [21.87%] vs 5 [41.66%], P =.026; 21 [65.62%] vs 4 [33.3%], P =.088; 4 [12.5%] vs none; respectively]. Mild MS was more frequent in patients with high blood flow velocity [6 [27.2%] vs 14 [63.6%], P =.03]. CONCLUSION: At linear regression analysis, only P-wave dispersion and LA diameter predicted the LAA mechanical dysfunction reflected as low LAA PEVs.     

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.     

Valsalva动作对评价左室舒张功能三种常用指标的影响

目的研究正常人Valsalva动作后前负荷降低是否引起舒张期二尖瓣口血流频谱、二尖瓣环运动速度及舒张早期左室血流传播速度三种指标变化以及如何变化。方法50例健康人,Valsalva动作前后分别测定舒张期二尖瓣口血流频谱、二尖瓣环运动频谱(DTI)和M型彩色多普勒舒张早期左室内血流传播速度(FPV),并进行Val-salva动作前后对照分析。结果Valsalva动作前后比较,舒张期二尖瓣口血流频谱E峰速度减低〔(80.6±16.3)cm/svs(65.9±13.3)cm/s,P＜0.01〕,A峰速度、E/A比值减低〔(54.2±10.2)cm/svs(49.5±10.4)cm/s和1.51±0.23vs1.37±0.29,P＜0.05),E峰减速时间DT延长〔(0.161±0.031)svs(0.192±0.05)s,P＜0.01〕。侧壁处二尖瓣环运动速度Eal降低〔(18.7±3.8)em/svs(16.3±3.7)cm/s,P＜0.01〕,Aal和Eal/Aal比值无显著变化〔(11.3±2.5)cm/svs(10.5±1.9)cm/s和1.72±0.46vs1.60±0.44,P＞0.05〕,室间隔侧Eas、Aas降低〔(14.7±2.8)cm/svs(13.1±2.4)cm/s和(9.9±1.7)cm/svs(8.8±1.9)cm/s,P＜0.01〕,Eas/Aas比值无显著变化(1.53±0.37vs1.54±0.33,P＞0.05),FPV无显著变化〔(55.87±6.66)cm/svs(55.32±10.22)cm/s,P＞0.05〕。结论作为评价左室舒张功能的指标,二尖瓣口血流易受前负荷影响,舒张期二尖瓣环运动速度与FPV相对不受前负荷影响,但二尖瓣环运动速度这一指标实际应用中更为优越。