Echocardiographic Assessment of Regional and Global Left Ventricular Function Wall-Motion Scoring in Parasternal and Apical Views Versus Apical Views Alone

The aim of the study was to examine the value of echocardiographic wall-motion scoring in apical views as compared to a conventional combination of apical and parasternal views. In 50 consecutive patients referred to coronary arteriography for potential revascularization, echocardiographic digital image loops of the left ventricle (LV) were recorded in parasternal long- and short-axis views and in apical long-axis, two-, and four-chamber views. Eight of 16 standardized LV segments appear both in the apical and in the parasternal views (group 1 segments). The remaining eight segments are visualized in the apical views only (group 2). Using a cross-over design, two cardiologists independently performed regional wall-motion scoring based on apical views, respectively, based on the combination of parasternal and apical views. Using the conventional approach (parasternal and apical views) 98% of the total 800 segments were scored as compared to 95% when using the mere apical approach (P < 0.05); 94% of the 800 segments were scored from both approaches. The regional wall-motion score was identical in 76% of group 1 segments and in 77% of group 2 segments. It diverged, at most, one score in 94% of group 1 segments and in 91% of group 2 segments (P > 0.05). LV ejection fraction (EF) calculated on the basis of average wall-motion score exclusively assessed from the apex differed little from angiographic EF (mean difference 2.0%, 95% confidence limits ± 6.6%). Intraobserver variability of wall-motion scores (n = 25 patients) was small and almost identical for the two cardiologists. Similarly, interobserver variability was small and identical for apical views and conventional views. We conclude that there is no substantial loss of information when echocardiographic evaluation of regional and global left ventricular function is performed solely from the apical approach.     

Nearly asymptomatic left ventricular apical ballooning after a hit-and-run accident

Tako-tsubo cardiomyopathy is a syndrome that mimics acute myocardial infarction consisting of typical chest pain with acute onset and transient left ventricular wall-motion abnormalities. We present a case of a 53-year-old woman with nearly asymptomatic apical ballooning after a hit-and-run car accident. No blunt force impact occurred over the precordial area. Typical chest pain or dyspnea was not present at any time. Electrocardiogram showed ST-segment elevation and T-wave inversion. Cardiac catheterization revealed the absence of coronary stenosis. Whereas left ventriculography and cardiac magnetic resonance imaging showed apical akinesia and hypercontractility of the basal segments (apical ballooning). Left ventricular systolic function recovered from ejection fraction 34% to 55% in ten days and echocardiographic wall abnormalities returned to normal.     

Predictors of left ventricular thrombus formation in patients with anterior myocardial infarction: role of activated protein C resistance

BACKGROUND: Left ventricular mural thrombus formation is a well-recognised consequence of acute anterior myocardial infarction. The vast majority of left ventricular thromboses occur in patients with anterior myocardial infarction and depressed left ventricular function. OBJECTIVE: To evaluate the factors predicting left ventricular thrombus formation in patients similar for left ventricular function and left ventricular score indexes. METHODS: We evaluated 45 consecutive patients who met the inclusion criteria of anterior myocardial infarction resulting in apical, anterior or septal asynergy (akinesia, dyskinesia), without non-Q-wave myocardial infarction, dilated cardiomyopathy, or renal or hepatic dysfunction. Patients were divided into two groups: group I with, and group II without, left ventricular mural thrombus. The groups were compared for clinical, echocardiographic and hematologic parameters (activated protein C resistance (APC-R), protein S and antithrombin III). RESULTS: Smoking and ACP-R were significantly greater in group I than in group II (P < 0.05 and P < 0.005 respectively). Multivariate regression analysis showed that APC-R was an independent risk factor for left ventricular thrombus formation in the patient group selected. Antithrombin III and protein S concentrations were not statistically different between two groups. All other clinical and echocardiographic characteristics of the patients were similar in both groups. CONCLUSION: APC-R is an independent risk factor for left ventricular thrombosis in patients with anterior myocardial infarction resulting in septal or anterior and apical akinesia or dyskinesia.     

Use of cyclic variation of integrated backscatter to assess contractile reserve and myocardial viability in chronic ischemic left ventricular dysfunction

The detection of viable myocardium has important implications for management, but use of stress echocardiography to detect this is subjective and requires exposure to dobutamine. We investigated whether cyclic variation (CV) of integrated backscatter (IB) from the apical views could provide a resting study for detection of contractile reserve (CR) and prediction of myocardial viability in 27 patients with chronic ischemic left ventricular (LV) dysfunction. Repeat echocardiography was performed after 6.7 +/- 3.8 months of follow-up; 14 patients underwent revascularization and 13 were treated medically. Using a standardized dobutamine echocardiography (DbE) protocol, images from three apical views were acquired at 80-120 frames/sec at rest and during stress. CR was identified if improvement of wall motion was observed at low dose (5 or 10 microg/kg/min) DbE. Myocardial viability was characterized by improvement at follow-up echocardiography in patients with revascularization. CVIB at rest and low dose dobutamine were assessed in 194 segments with resting asynergy (severe hypokinesis or akinesis), of which 88 (45%) were in patients who underwent revascularization. Of these, CVIB could be measured in 190 (98%) segments at rest and 185 (95%) at low dose dobutamine. Sixty-two (33%) segments had CR during low dose DbE and 50 (57%) segments showed wall-motion recovery (myocardial viability) at follow-up echocardiography. Segments with CR had significantly higher CVIB at rest (P < 0.001) and low dose dobutamine (P = 0.005) than segments without CR. Using optimal thresholds of CVIB (> 8.2 dB) at rest, the accuracy of CVIB for detecting CR was 70%. Compared with nonviable segments, viable segments had significantly higher CVIB at rest (P < 0.001) and low dose dobutamine (P < 0.001). Using optimal thresholds of CVIB (> 5.3 dB) at rest, the accuracy of CVIB for detecting myocardial viability was 85%, which was higher than that in conventional DbE (62%, P < 0.01). Thus, assessment of CVIB from the apical views is a feasible and accurate tool for detecting CR and predicting myocardial viability in chronic LV dysfunction.     

Contrast echocardiography for the diagnosis of left ventricular thrombus in anterior myocardial infarction

Although detecting left ventricular thrombus in anterior myocardial infarction is important for the prevention of embolic events, imaging of apical thrombus is often difficult using conventional echocardiography. We examined whether contrast echocardiography improves sensitivity and specificity in detecting thrombus in the left ventricle in comparison with conventional echocardiography alone in patients with anterior myocardial infarction. Participants in this single-center prospective study comprised 392 patients with anterior myocardial infarction admitted between 2000 and 2006. After conventional echocardiography, all patients underwent contrast echocardiography (left ventricular opacification and myocardial contrast echocardiography) during intravenous drip infusion of contrast media at rest. Left ventricular thrombus was diagnosed based on left ventriculography or multidetector-row computed tomography (MDCT). Mural left ventricular thrombus was confirmed by left ventriculography and/or MDCT in 32 of 393 patients (8 %). Sensitivity and specificity of conventional echocardiography alone were 88 % and 96 %, respectively, compared with 100 % each with contrast echocardiography. Among the 32 patients with left ventricular thrombus, 25 patients (78 %) showed no perfusion in the anterior wall on myocardial contrast echocardiography, even with a four-beat interval. In conclusion, contrast echocardiography offers a clinically feasible and useful method for noninvasively evaluating left ventricular thrombus in anterior myocardial infarction.     

The effect of early postinfarction revascularization of asymptomatic patients on left ventricular remodeling.

BACKGROUND: Patients with angina after a Q-wave myocardial infarction benefit from elective revascularization, but it is not known whether asymptomatic patients, including those with a totally occluded infarct-related artery, improve after revascularization. OBJECTIVE: To determine the effect of early postinfarction revascularization of asymptomatic patients on left ventricular remodeling. METHODS: We prospectively studied 31 consecutive asymptomatic patients (aged 57 +/- 2 years, 24 with anterior infarcts) after Q-wave myocardial infarction with > or = 70% stenosis of the infarct-related artery (IRA) who underwent early elective revascularization (days 4-10 after myocardial infarction). Group I consisted in patients with a totally occluded IRA (n = 10), and group II consisted in patients with a patent, though stenosed, IRA (n = 21). Resting echocardiography and low-dose dobutamine echocardiography were performed at baseline (day 3 +/- 1), and rest echocardiography was repeated after an 8-week follow-up. Significant myocardial viability was defined as > or = 2 wall segments improved (in a 16-segment model of left ventricle) versus baseline, and significant functional recovery as > or = 2 segments improved versus baseline on follow-up examination. Left ventricular end-systolic volume indices (ESVI) and end-diastolic volume indices and ejection fractions were measured by using a modified version of Simpson's rule (using apical two-chamber and four-chamber views). RESULTS: The left ventricular ESVI of patients in group I had decreased by 4.2 +/- 1.9 ml/m2, whereas for patients in group II the left ventricular ESVI had increased by 4.2 +/- 1.7 ml/m2 (P = 0.006). Similarly, the left ventricular end-diastolic volume index had decreased by 0.7 +/- 2.4 ml/m2 versus baseline at follow-up for patients in group I and increased by 7.8 +/- 2.1 ml/m2 for patients in group II (P = 0.02). The left ventricular ejection fraction increased by 7.3 +/- 3% for patients in group I and decreased by 0.4 +/- 2% for patients in group II (P = 0.04). CONCLUSION: There is less global left ventricular remodeling, a potentially deleterious process, after elective revascularization early after Q-wave myocardial infarction in asymptomatic patients who had had a totally occluded IRA before revascularization than there is in patients who had already had a patent, though stenosed, IRA before revascularization. These results suggest that restoration of patency of IRA after a Q-wave myocardial infarction is beneficial even for asymptomatic patients.     

Silent ischemia and loss of reversible myocardial dysfunction following myocardial infarction

Sixty-seven asymptomatic patients were enrolled after a first uncomplicated myocardial infarction (MI) so as to study the relevance of reversible myocardial dysfunction in determining left ventricular function soon after the acute episodes and 12 months later. Moreover, the potential role of silent ischemia in conditioning the evolutive aspects of contractile dysfunction has been investigated. Postextrasystolic potentiation during two-dimensional echocardiographic (2-D echo) monitoring has been used to detect the presence of viable myocardium in asynergic myocardial segments. Results of electrocardiographic (ECG) ambulatory monitoring at predischarge determined patient groups: Group A included 49 patients without ST changes during monitoring, while Group B included 18 patients with silent ischemia. Incidence of reversible myocardial dysfunction was similar in the two study groups (82 vs. 86%, p = NS). Group B patients were older (59.6 ± 6.7 vs. 50.6 ± 10.6 years, p < 0.015) and had lower ejection fractions (EFs, 43.4 ± 6.4% vs. 51.2 ± 8.3%, p = 0.026) and higher at-rest wall-motion scores (WMSs, 11.4 ± 5.9 vs. 7.2 ± 3.8, p = 0.019). Left ventricular end-diastolic volume (LVEDV) and potentiated WMS did not differ. At 1-year examination, Group B patients exhibited a greater LVEDV index (96 ± 6.5 vs. 70.7 ± 14 ml/m², p < 0.002) with a worsening both in rest and in potentiated wall-motion score index (12.8 ± 4.6 vs. 5.3 ± 1.8, p < 0.001; 9.2 ± 3.6 vs. 4.8 ± 2.2, p < 0.001, respectively). Left ventricular EF remained significantly depressed in Group B patients (42 ± 8.7% vs. 55.5 ± 8.1%, p < 0.002). Over the first year, spontaneous functional recovery of asynergic segments occurred in 60% of Group A patients with reversible myocardial dysfunction at early study. In Group B patients, only three (20%) showed functional recovery, and a small number (24%) maintained reversible contractile dysfunction. Thus, reversible contractile dysfunction is a common finding in asymptomatic patients without clinical ischemia soon after a first MI. The presence of silent ischemia during ambulatory ECG monitoring identifies a group of patients at high risk of further loss of myocardial viability and progressive left ventricular dilation over the first year.     

High risk of cardiogenic cerebral embolism for very elderly patients in sinus rhythm with left atrial appendage flow velocity below 50 cm/s

Recent clinical trials have demonstrated that patients in sinus rhythm after cardioversion are still at risk of suffering from embolic events, but the precise mechanisms underlying the occurrence of cardiogenic cerebral embolism remain to be determined. All 72 patients aged 75 or over who were consecutively referred to our department between October 2003 and March 2006 were divided into three groups; these were: group 1, 17 patients in sinus rhythm after cardioversion; group 2, 18 patients without any history of atrial fibrillation; and group 3, 37 patients with chronic atrial fibrillation. Using transesophageal echocardiography, we evaluated the left atrial appendage flow velocity, left atrial appendage dimension, spontaneous echocardiographic contrast in the left atrium, and the presence of thrombus in the left atrial appendage. Left atrial appendage flow velocity was significantly lower in group 1 compared with group 2 (38.2 ± 6.1 vs 61.4 ± 7.4 cm/s, P  < 0.001), but was even lower in group 3 (25.1 ± 9.8 cm/s, P  < 0.001 vs group 1). Spontaneous echocardiographic contrast in the left atrium, thrombus in the left atrial appendage and cardiogenic cerebral embolism showed a close relationship with left atrial appendage flow velocity, and were more frequent when left atrial appendage flow velocity was less than 50 cm/s. Very elderly patients in long-term maintenance of sinus rhythm with an left atrial appendage flow velocity of less than 50 cm/s would have a high risk of cardiogenic cerebral embolism.     

Late effects of intracoronary streptokinase on regional wall motion, ventricular aneurysm and left ventricular thrombus in myocardial infarction: results from the Western Washington Randomized Trial

To determine whether intracoronary streptokinase improves late regional wall motion or reduces left ventricular aneurysm or thrombus formation in patients with acute myocardial infarction, two-dimensional echocardiography was performed at 8 +/- 3 weeks after infarction in 83 patients randomized to streptokinase (n = 45) or standard therapy (n = 38) in the Western Washington Intracoronary Streptokinase Trial. Among the patients treated with streptokinase, the average time to treatment was 4.7 +/- 2.5 hours after the onset of chest pain, and 67% had successful reperfusion. Regional wall motion was assessed in nine left ventricular segments on a scale of 1 to 4 (normal, hypokinetic, akinetic and dyskinetic). Left ventricular thrombus formation was interpreted as positive, equivocal or negative. All patients received anticoagulant therapy in the hospital and 52 received such therapy after hospital discharge. The mean (+/- SD) global (1.5 +/- 0.4 in both groups) and regional wall motion scores in the streptokinase-treated and control groups were not significantly different. The prevalence of aneurysm was 16% in both groups. Left ventricular thrombus was identified in only five patients (positive identification in four, and equivocal in one), all in the streptokinase-treated group (p = NS). There were also no differences between streptokinase and control treatment in any of the echocardiographic variables in subgroups of patients with anterior infarction, inferior infarction, no prior infarction or reperfusion with streptokinase. It is concluded that intracoronary streptokinase given relatively late in the course of acute myocardial infarction does not result in improved global or regional wall motion or a reduction in left ventricular thrombus or aneurysm formation in survivors studied 2 months after myocardial infarction.     

超声斑点追踪技术对系统性红斑狼疮患者局部心肌收缩功能的评价

目的 应用超声斑点追踪技术(STI)评价系统性红斑狼疮(SLE)患者局部心肌收缩功能.方法 ①SLE组36例,健康对照组24名,分别记录并存储每位被检者心尖位左心室3个长轴切面高帧频二维动态图像,应用自动功能成像软件(AFI)检测左心室壁18节段收缩期峰值应变(S),记录并比较各参数测值.②在对照组中随机取20名被检者,双盲条件下,由同一观察者不同时间及2名观察者分别测量每位被检查者心肌收缩期峰值应变值,2组问计量资料比较采用非配对t检验,并利用Pearson相关分析法分析其相关性.结果 对照组左心室各壁S值自基底段向心尖段逐渐增加,心尖段与基底段、中间段差异有统计学意义(P＜0.05),不同室壁对应节段间差异无统计学意义(P＞0.05);同一室壁各节段心肌收缩期峰值应变达峰时间基本一致.SLE组除前间隔和前壁外各室壁S值自基底段向心尖段逐渐增加[(-18.7+4.2)%,(-16.3±9.4)%,(-18.1±10.5)%与(-19.0±9.0)%,(-18.6±7.9)%,(-17.7±1.4)%],心尖段与基底段、中间段差异均无统计学意义(P＞0.05);SLE组各室壁各节段S值明显低于对照组,差异均有统计学意义(P＜0.05);SLE组同一室壁各节段心肌收缩期峰值应变达峰时间一致性差.同一观察者不同时间及2名观察者问对心肌收缩期峰值应变值的测量相关性良好(P＜0.01).结论 STI技术发现SLE患者与健康对照组差异有统计学意义,SLE患者心肌损害表现为左室局部心肌收缩期峰值应变减低.

Abstract：

Objective To assess the vaIue of speckle tracking imaging (STI) in quantifying the regional myocardial strain in systemic lupus erythematosus (SLE) group.Methods ① Sixty subjects were divided into SLE group and normal group.High frame rate two-dimensional images were recorded from the apical two-chamber view,long-axis view and four-chamber view of the left ventricle (LV).Peak systolic strain of each view of 18 segments were measured by automated functional imaging (AFI) software of 2-DSE.All parameters were compared between the two groups.② Twenty cases were randomly taken from the normal group.The same observer at different times and two observers measure the strain of left ventricular respectively.The results of the measurement between the two groups were compared with unpaired t test and its relevance was analyzed using Pearson's correlation analysis.ResultsLeft ventricular two-dimensional longitudinal strain gradually increased from the base to apex in the normal group.There were statistically differences between the apical segments and the basal,middle segments of every left ventricular wall (P＜0.05).The same wall segment time to peak myocardial systolic peak strain was consistent.Left ventricular two-dimensional longitudinal strain gradually increased from the base to apex in the SLE group,except for the anterio-septal and anterior wall [ (-18.7±4.2)％,(-16.3±9.4)％,(-18.1±10.5)％ vs (-19.0±9.0)％,(-18.6±7.9)％,(-17.7±1.4)％ ].There was no statistically significant difference between the apical segments and the basal,middle segments of every left ventricular wall(P＞0.05).All parameters of S were significantly higher in the normal group than those of the SLE group.The difference was statistically signoficant (P＜0.05).The time to peak systolic peak strain of every segments was not consistent.The results from the same observer at different times and peak systolic myocardial strain measurements by the two observers were correlated well(P＜0.01).Conclusion The myocardial function assessment by STI technology in the SLE patients is significantly different from that of the normal control:SLE patients with left ventricular myocardial damage can be manifested as reduced regional myocardial systolic peak strain.     

Impaired left ventricular synchronicity in hypertensive patients with ventricular hypertrophy

OBJECTIVES: The influence of left ventricular hypertrophy (LVH) on left ventricular synchronicity, and the prevalence of left ventricular dyssynchrony in hypertensive patients with LVH are unknown. The purpose of this study was to determine the influence of LVH on left ventricular synchronicity in hypertensive subjects. METHOD: Tissue Doppler imaging (TDI) was performed in 115 hypertensive and 30 control individuals. Hypertensive patients were divided into a LVH group and a non-LVH group according to the left ventricular mass index (LVMI). Diastolic and systolic asynchrony was determined by measuring the maximal differences in time to peak myocardial systolic contraction (Ts-max) and early diastolic relaxation (Te-max) between any two of the left ventricular segments and the standard deviation of time to peak myocardial systolic contraction and early diastolic relaxation of all 12 segments. RESULTS: Ts-max was greater in both the non-LVH and LVH groups than in controls, (96.68 +/- 26.21 versus 79.30 +/- 25.19 versus 53.20 +/- 15.24 ms, both P < 0.001) and in the LVH group than in the non-LVH group (96.68 +/- 26.21 versus 79.30 +/- 25.19 ms, P < 0.01). Te-max was prolonged in both patient groups, being most advance in the LVH group (67.39 +/- 11.01 versus 57.18 +/- 11.42 versus 46.72 +/- 13.24 ms, both P < 0.001 versus control group and P < 0.001 versus non-LVH group). LVH patients had shown a greater prevalence of both systolic and diastolic asynchrony than non-LVH patients. A Ts-max value greater than 88 ms had 68% sensitivity and 71% specificity for detecting hypertensive patients with LVH. CONCLUSION: Left ventricular systolic synchronicity was impaired in hypertensive patients with LVH. TDI was shown to be useful for the detection of myocardial abnormalities in such patients.     

Estimation of global left ventricular function from the velocity of longitudinal shortening

AIMS: To determine if global ventricular function can be assessed from the long-axis contraction of the left ventricle, we compared pulsed-wave Doppler myocardial imaging of mitral annular motion to radionuclide ventriculography. METHODS AND RESULTS: We studied 51 patients (56 +/- 10 years, 11 women) with a radionuclide ejection fraction of 52 +/- 13% (15%-70%). Peak systolic velocities of medial and lateral mitral annular motion correlated with ejection fraction (0.55 and 0.54, respectively; P < 0.001), as did the time-velocity integrals (0.57 and 0.58, respectively; P < 0.001). Correlations were higher in normal ventricles (0.62-0.69) than in patients with previous myocardial infarction (0.39-0.64). Patients with anterior myocardial infarction had the lowest correlations (0.39-0.46). The best differentiation of normal (> or = 50%) from abnormal (< 50%) ejection fraction was provided by peak systolic velocity > or = 8 cm/sec for the medial (sensitivity 80%, specificity 89%) or lateral (sensitivity 80%, specificity 92%) mitral annulus. CONCLUSION: Global left ventricular function can be estimated by recording mitral annular velocity. The implementation of a cutoff limit of 8 cm/sec gave a simple guide for differentiating between normal and abnormal left ventricular systolic function that might be useful clinically in patients without regional wall-motion abnormalities. However, in patients with important segmental wall-motion abnormalities during systole, left ventricular longitudinal shortening is an imperfect surrogate for ejection fraction.     

Assessment of the Systolic Left Ventricular Myocardial Velocity Profile and Gradient Using Tissue Doppler Imaging in Patients with Hypertrophic Cardiomyopathy

To determine the systolic characteristics of the hypertrophied myocardium in patients with hypertrophic cardiomyopathy (HCM), we evaluated the left ventricular [left ventricle (LV)] myocardial velocity profile (MVP) and gradient obtained from tissue Doppler imaging (TDI). Transmural wall-motion velocities in the ventricular septum and LV posterior wall were recorded in 12 patients with asymmetric septal hypertrophy and 12 healthy volunteers, and their profiles and gradients were determined. The maximum systolic myocardial velocity gradient in the ventricular septum was significantly lower in the HCM group than in the control group (0.88 ± 0.35 versus 2.24 ± 0.41; P < 0.001), whereas the gradient in the LV posterior wall was only slightly lower in the HCM group than in the control group (2.69 ± 0.82 versus 3.45 ± 0.96). In the control group, the MVPs in the ventricular septum and LV posterior wall were closely linear, suggesting that the transmural velocity is uniform during systole. MVPs in the ventricular septum and LV posterior wall in the HCM group also were closely linear, whereas the distribution of velocities in the ventricular septum was fairly dispersed compared with the control group. The myocardial velocity gradient on the right ventricular side of the ventricular septum decreased or disappeared in the patients with HCM, suggesting a nonuniform distribution of velocities. In conclusion, the MVP and gradient obtained from TDI may represent new indices for evaluating regional LV contractile abnormality in patients with HCM.     

双核素单光子断层显像评价骨髓单个核细胞移植后急性心肌梗死患者存活心肌变化

目的 利用双核素[^201 铊（Tl）及^18 F-脱氧葡萄糖（FDG）]单光子断层显像（SPECT）方法评价经冠状动脉自体骨髓单个核细胞（BM-MNC）移植对急性心肌梗死患者心功能和存活心肌的影响。方法 40例首次ST段抬高急性心肌梗死患者,成功完成PCI术后,随机分为细胞移植组（n=20）和对照组（n=20）,急诊冠状动脉造影术同时,经微导管于梗死相关动脉内支架远端注入自体BM-MNC悬液或等量的肝素生理盐水。研究终点为PCI术后6个月时双核素（^201 Tl及^18F-FDG）SPECT测定存活心肌的变化。结果 随访6个月时,两组患者左心室射血分数均有显著提高,但移植组患者左室射血分数改善幅度更显著[（7．6±2．8）％比（3．0±2．8）％,P〈0．001]。^201 Tl-SPECT显示移植组患者左心室心肌灌注明显改善,心肌灌注缺损面积减少（6．7±3．0）％,同时^18 F—FDG-SPECT结果显示梗死边缘区心肌灌注-代谢不匹配面积明显增加,提示存活心肌明显增加。结论 自体BM-MNC可以改善急性心肌梗死后梗死边缘区心肌灌注,增加局部存活心肌,提高左心室功能。     

Evaluation of Left Atrial Appendage Functions in Patients with Thrombus and Spontaneous Echo Contrast in Left Atrial Appendage by Using Color Doppler Tissue Imaging

Objective: Thrombus and spontaneous echo contrast (SEC) develops in the left atrial appendage (LAA) when LAA function is disturbed. Decrease of left atrial appendage emptying velocity shows LAA dysfunction. The purpose of this study is to examine the incidence of SEC and/or thrombus in LAA in patients with acute myocardial infarction and to assess the LAA function using color Doppler tissue imaging (CDTI) of the patients with detected SEC and/or thrombus. Method and Results: Eighty‐four patients with acute myocardial infarction were included in the study. Spontaneous echo contrast and/or thrombus were observed in 24 (29%) of the 84 patients who were categorized as group 1 (mean age 59 ± 12 years). Sixty patients (71%) without thrombus and/or SEC in LAA were categorized as group 2 (mean age 58 ± 8 years). Left atrial diameters and left ventricular ejection fraction were measured by using transthoracic echocardiography. Left atrial appendage emptying and LAA filling velocity were measured by transesophageal Doppler echocardiography. Systolic appendage tissue velocities (SaV cm/s) were measured at the basal, mid, and tip of medial wall of LAA by transesophageal CDTI. Group 1 had significantly decreased LAA emptying velocities, mid SaVs, and left ventricular ejection fractions compared to group 2 (37 ± 9 cm/s vs 55 ± 22 cm/s, 3.1 ± 1.6 cm/s vs 3.7 ± 1.2 cm/s, and 47 ± 13% vs 58 ± 10%, respectively, P = 0.002, P = 0.04, P = 0.03). Group 1 had significantly increased left atrial diameters compared to group 2 (40 ± 5 mm vs 36 ± 6 mm P = 0.001). Left atrial appendage‐filling velocities, basal SaVs and tip SaVs in group 1 were lower than those in group 2 but not significantly. Conclusions: Mid‐SaV of LAA medial wall and LAA emptying velocity decrease in patients with thrombus and/or SEC were an indication of functional disorder of LAA. Color Doppler tissue imaging appears to be a clinically applicable and reliable imaging technique that allows quantitative assessment of regional LAA systolic function.     

Doppler-derived mitral deceleration time as an early predictor of left ventricular thrombus after first anterior acute myocardial infarction

BACKGROUND: The relation between left ventricular (LV) diastolic function and LV thrombus has not yet been fully investigated. The aim of this study was to determine whether early assessment of Doppler-derived mitral deceleration time (DT), a measure of LV compliance and filling, may predict LV thrombus formation after acute myocardial infarction. METHODS AND RESULTS: Two-dimensional and Doppler echocardiographic examinations were performed in 98 consecutive patients (aged 57 +/- 12 years; 8 women) with first acute myocardial infarction. The patients were studied within 24 hours and at days 3, 7, 15, and 30 after arrival to the coronary care unit. Mitral flow velocities were obtained from the apical 4-chamber view with pulsed Doppler. LV thrombus was detected in 20 of 98 patients. Patients were divided into 2 groups according to LV thrombus formation: group 1 (n = 20) with thrombus and group 2 (n = 78) without thrombus. Mitral E-wave DT was significantly shorter in group 1 than group 2 (134 ms vs 175 ms; P <.001). Patients in group 1 had significantly larger LV end-diastolic and end-systolic volumes and a higher wall motion score index than patients in group 2 (133 +/- 39 mL vs 112 +/- 41 mL, P =.03; 83 +/- 34 mL vs 59 +/- 30 mL, P =.003; and 1.8 +/- 0.3 mL vs 1.5 +/- 0.3 mL, P =.007, respectively). The LV ejection fraction was significantly lower in group 1 than in group 2 (39% +/- 13% vs 48% +/- 12%; P =.004). In a multivariate regression analysis, mitral E-wave DT was identified as an independent variable related to development of LV thrombus (P =.04). CONCLUSIONS: Doppler-derived mitral DT is superior to conventional clinical and 2-dimensional echocardiographic assessment in estimating the risk of left ventricular thrombosis after myocardial infarction.     

速度向量成像技术评价心血管疾病高危病人左心室收缩功能的临床研究

目的应用速度向量成像(VVI)技术评价心血管疾病高危病人左心室收缩功能,并分析其与心血管疾病高危因素的关系。方法选取85例心血管疾病高危病人为高危组,同期健康体检者50名为对照组,常规超声心动图获取左房收缩末期内径(LAESD)、左室舒张末期内径(LVEDD)、室间隔厚度(IVS)、左室后壁厚度(LVPW)及左室射血分数(LVEF)。并采集心尖四腔、三腔、二腔长轴二维图像,测量各节段及整体纵向收缩峰值应变(GLS),分析左心室GLS与三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)及收缩压、舒张压的相关性。结果高危组各亚组LVEF、LVEDD、LAESD、IVS、LVPW值与对照组比较,差异均无统计学意义(P>0.05);高危组左心室GLS(21.83±1.80)%,小于对照组的(23.00±1.97)%,差异有统计学意义(P<0.05)。相关分析显示,左心室整体平均纵向应变值与TG、LDL-C及收缩压、舒张压均无明显相关性(r=-0.148,P=0.086;r=-0.168,P=0.052;r=-0.098,P=0.260;r=-0.075,P=0.386)。结论VVI可通过心肌纵向应变评价左室心肌的收缩功能,发现心血管疾病高危病人的亚临床左心收缩力异常。     

超声二维斑点追踪技术对单纯冠状动脉左前降支狭窄患者左心室收缩功能的评价

目的探讨二维纵向应变(LS)、左心室壁整体扭转角度(LV-tor)在二维超声未探及左心室壁运动异常,而冠状动脉存在单纯左前降支(LAD)不同程度狭窄时,对左心室壁节段及整体收缩功能改变的评价价值。方法入选行冠状动脉造影的患者75例,取造影正常者27例为对照组,而单纯LAD狭窄50%～75%的患者25例(A组)、单纯LAD狭窄≥75%的患者23例(B组),分别采集常规超声心动图的心尖两腔、心尖左心室长轴切面及左心室短轴基底水平、心尖水平切面的16个室壁阶段二维灰阶图像。应用GE Echo PAC软件测量仅由LAD供血的相应左心室壁节段收缩期峰值的LS,以及左心室基底段总扭转角度(Rot-base)、心尖段总扭转角度(Rot-apex)并计算出LV-tor,静息状态下应用M型超声测定左心室壁运动幅度、左心室射血分数(LVEF)、短轴缩短率(FS)等常规参数。结果 A组与对照组比较,LS值和LV-tor的差异均无统计学意义(均为P>0.05)。B组与对照组、A组比较,LAD供应左心室壁相应节段的LS值(-24.2±1.8比-25.2±1.8和-25.1±1.4,P=0.037)和LV-tor(16.4±1.2比17.2±1.1和16.7±1.1,P=0.041)差异均有统计学意义;而3组间比较,LVEF和FS等差异均无统计学意义(均为P>0.05)。结论当单纯LAD狭窄率≥75%时,LS值可敏感地反映出左心室壁节段收缩功能改变,而LV-tor可敏感地反映出左心室壁整体收缩功能的改变;左心室壁除相应节段出现收缩功能减低外,整体收缩功能也受到影响。     

Left ventricular thrombosis after anterior myocardial infarction with and without thrombolytic treatment

Abstract. Objectives. To examine the incidence of left ventricular thrombus in patients with anterior myocardial infarction, with and without streptokinase treatment. To identify predictors of thrombus development. Design. Consecutive patients prospectively studied during the hospitalized period. Echocardiography was performed within 3 days of admission and before discharge. Setting. Umeå University Hospital, a teaching hospital in Northern Sweden. Subjects. Ninety-nine patients with anterior myocardial infarction of whom 74 were treated with streptokinase. Main outcome measures. Left ventricular thrombus and left ventricular segmental myocardial function. Results. During the hospital stay, a thrombus developed in 46% (95% confidence interval [CI], 35–57%) of the patients in the thrombolysis group and in 40% (95% CI, 21–59%) of the patients in the non-thrombolysis group. No difference in left ventricular segmental myocardial function was found between the thrombolysis and non-thrombolysis groups at hospital discharge. No embolic events were observed. The occurrence of a left ventricular thrombus at hospital discharge was significantly associated with previous myocardial infarction, peak enzyme levels, left ventricular global and segmental dysfunction and an increased dose of peroral diuretics or use of parenteral diuretics. In a multiple logistic regression model, left ventricular segmental dysfunction was the most important predictor of left ventricular thrombus. Conclusion. Thrombolytic treatment with streptokinase does not prevent the development of a left ventricular thrombus but the risk of embolic complications is low. The left ventricular segmental myocardial score can be used to assess the risk of thrombus development, also, after thrombolysis.     

Cardiac thrombus in dilated cardiomyopathy. Relationship between left ventricular pathophysiology and left ventricular thrombus

The relationship between left ventricular thrombus and left ventricular dynamics in dilated cardiomyopathy (DCM) was studied by echocardiography and postmortem examination. The subjects were 57 patients with DCM, 40 were survival patients examined by echocardiography and 17 were autopsy patients. Systemic or pulmonary embolism occurred in 10 of 57 patients, 4 of 40 survival patients and 6 of 17 autopsy patients. Intracardiac thrombus was detected in 11 of 40 survival patients and was found in 8 of 17 autopsy patients. Left ventricular segmental wall motion abnormalities were observed in all 40 patients examined by two-dimensional echocardiography and apical dyskinesis or akinesis was observed more frequently in patients with left ventricular thrombus than in patients without left ventricular thrombus. Of 33 patients examined by pulsed Doppler echocardiography, Doppler ejection flow signals in the apical long axis view were recorded in 9% at the apex, in 17% at the middle portion and in 57% at the portion near the interventricular septal center. The signals at the portion near the interventricular septal center were recorded in only 2 patients with left ventricular thrombus but in 66% of patients without left ventricular thrombus. Systemic or pulmonary embolism and intracardiac thrombus occurred less frequently in patients treated with warfarin than in patients without warfarin. These results indicate that endomyocardial and blood flow disorders of the left ventricle play important roles in the occurrence of left ventricular thrombus and that anticoagulant therapy is useful for the prevention of systemic or pulmonary embolism and cardiac thrombus.