Usefulness of contrast echocardiography for assessment of left ventricular thrombus after acute myocardial infarction

Fifty consecutive patients referred to a coronary care unit for acute anterior myocardial infarction with ST-segment elevation underwent coronary arteriography, left ventricular (LV) angiography, and revascularization. Transthoracic echocardiography was systematically performed using fundamental imaging, second harmonic imaging, and contrast agents to assess the LV chamber. Six patients (12%) presented with a confirmed LV mural thrombus. Thirty-five percent of patients with time to revascularization>3 hours presented with an LV mural thrombus versus 0 patients with time to revascularization3 hours.     

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.     

Long-term prospective assessment of left ventricular thrombus in anterior wall acute myocardial infarction and implications for a rational approach to embolic risk

To prospectively assess the predictive value of left ventricular (LV) thrombus anatomy for defining the embolic risk after acute myocardial infarction (AMI), 2 comparable groups of patients with a first anterior AMI (group A, 97 thrombolysed patients; group B, 125 patients untreated with antithrombotic drugs [total 222]) underwent prospective serial echocardiography (follow-up 39 +/- 13 months) at different time periods. LV thrombi were detected in 26 patients in group A (27%) and in 71 in group B (57%; p <0.005). Embolism occurred in 12 patients (5.4%; 1 in group A [1%] vs 11% in group B [9%], p < 0.04). At multivariate analysis, thrombus morphologic changes were the most powerful predictor of embolism (p <0.001), followed by protruding shape (p <0.01) and mobility (p <0.02). In patients untreated with thrombolysis, a higher occurrence of thrombus morphologic changes (48% vs 8%, p <0.002) and protruding shape (69% vs 31%, p <0.002) were observed, whereas thrombus mobility was similar in the 2 groups (18% vs 8%, p = NS). Thrombus resolution occurred more frequently in thrombolysed patients (85% vs 56%, p <0.002). Thus, after anterior AMI, changes in LV thrombus anatomy frequently occur and appear the most powerful predictor of embolization. A minor prevalence of thrombus, a more favorable thrombus anatomy, and a higher resolution rate may contribute to reduce embolic risk after thrombolysis.     

Left ventricular thrombus formation after first anterior wall acute myocardial infarction

The characteristics of the left ventricle and coronary arteries associated with left ventricular (LV) thrombus in patients with recent anterior acute myocardial infarction were defined. Of 77 patients studied, 35 (46%) had LV thrombi. The presence of LV thrombus was not correlated to the extent of coronary artery disease. The frequency of LV thrombus progressively increased with groups of increasing wall motion abnormality as determined by the extent of akinesia and dyskinesia (%AD) (%AD 0 to 14, thrombus present in 3 of 16 [19%], %AD 15 to 29, thrombus in 8 of 27 [30%]; %AD greater than or equal to 30%, thrombus in 24 of 34 [71%]; p less than 0.001) and with increasingly severe degrees of early ventricular shape change (normal or mildly abnormal contour, 16% with thrombus; moderately abnormal contour, 36% with thrombus; severely abnormal contour, 70% with thrombus; p less than 0.001). Patients with thrombi had higher diastolic (249 +/- 55 vs 225 +/- 48 ml; p less than 0.05) and systolic (158 +/- 48 vs 120 +/- 45 ml; p less than 0.001) volumes than patients without thrombi, respectively. A stepwise discriminant analysis identified ejection fraction, extent of early shape change and LV end-diastolic pressure as independent correlates of LV thrombus after acute myocardial infarction.     

Usefulness of myocardial contrast echocardiography in predicting global left ventricular functional recovery after anterior wall acute myocardial infarction

Although multiple recent studies have shown that myocardial contrast echocardiography (MCE) reliably differentiates between regional stunning and necrosis after acute myocardial infarction (AMI), prognosis is more closely related to measures of global left ventricular systolic function. One hundred fifteen patients underwent baseline wall motion assessment and MCE 2 days after admission and follow-up echocardiography a mean of 69 days later. Good agreement was found between perfusion score index and follow-up wall motion score index, indicating that MCE performed early after anterior wall AMI may be clinically useful in routine post-AMI risk stratification.     

Serial changes in left ventricular diastolic indexes derived from Doppler echocardiography after anterior wall acute myocardial infarction

Restrictive ventricular filling pattern derived from Doppler echocardiography after anterior wall AMI may serve as an indicator of diastolic dysfunction due to initial myocardial stiffness and complications such as extension of the infarction, Dressier syndrome, septal rupture, or myocardial failure. Later changes, such as prolongation of deceleration time, may indicate remodeling process, healing of the complications of AMI, or improved revascularization.     

多普勒超声心动图评价急性心肌梗塞后左室重构及心功能改变

应用多普勒超声心动图对56例不同部位急性心肌梗塞（AMI）后患者及40例正常人左室结构（LVR）、收缩舒张功能参数进行对比分析研究。结果显示AMI后患者左室舒张及收缩末期内径、左心室舒张末期容积、左心室收缩末期容积、左室射血前期与射血时间比、舒张晚期峰值血流速度、A峰面积增大；射血分数、短轴缩短率、舒张早期峰值血流速度、E峰／A峰面积则降低，两组间比较有极显著性差异（P＜0．01）。认为AMI后患者心脏不同程度的发生了LVR及收缩舒张功能减退。     

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.     

Pulsed wave tissue Doppler-derived myocardial performance index for the assessment of left ventricular thrombus formation risk after acute myocardial infarction

Background

Assessment of left ventricular (LV) thrombosis risk after acute myocardial infarction (AMI) is important because of potential embolic sequelae that are reduced by oral anticoagulant agents. The goal of this study was to investigate whether early assessment of LV systolic and diastolic performance with pulsed wave tissue Doppler ultrasound scanning (PWTD) predicts LV thrombosis after AMI.

Methods

Two-dimensional and Doppler ultrasound scanning echocardiographic examinations were performed in 92 consecutive patients (age, 58 ± 10 years; 11 women) with first anterior AMI within 24 hours after arrival to the coronary care unit. From the apical 4-chamber view, the mitral annular velocities were recorded at the lateral corner of the mitral annulus with PWTD. The myocardial performance index (MPI), which combines parameters of both systolic and diastolic ventricular function, was calculated from the PWTD recordings. To analyze LV thrombus formation, the 2-dimensional echocardiographic examination was repeated on days 3, 7, 15, and 30. The patients were divided in 2 groups according to LV thrombus formation.

Results

LV thrombus was found in 32 of 92 patients (35%; group 1) and was not found in 60 patients (65%; group 2). The MPI was significantly higher in group 1 than in group 2 (0.73 ± 0.20 vs 0.53 ± 0.14; P <.001). When an MPI >0.6 was used as the cutoff, LV thrombus formation could be predicted with a sensitivity rate of 81%, a specificity rate of 73%, a positive predictive value of 62%, and a negative predictive value of 88%. In multivariate analyses, only MPI and LV wall motion score index were independent predictors of LV thrombus formation (P = .038 and P = .047, respectively).

Conclusions

The MPI derived with PWTD soon after admission appears to be a useful parameter for assessing the risk of LV thrombosis after AMI. Patients with an MPI >0.6 after AMI seem to be at a higher risk for thrombus formation.     

Clinical correlations in patients with acute myocardial infarction and left ventricular thrombus detected by two-dimensional echocardiography

Eleven of forty-nine patients with acute myocardial infarction had left ventricular thrombus identified by two-dimensional echocardiography. The patients with thrombi had a greater incidence of transmural infarction, high-grade ventricular ectopy on ambulatory monitoring and lower radionuclide ejection fractions than the patients without thrombi. Most of the patients were receiving full-dose heparin and/or warfarin anticoagulation from the time of admission to the hospital. Thus the thrombi either developed prior to hospital admission or developed during anticoagulation therapy. Two patients with thrombi had peripheral emboli complicating their infarction. One of these patients was undergoing anticoagulation at the time of his embolus.     

Usefulness of mitral regurgitation in protecting against left ventricular thrombus after acute myocardial infarction

In conclusion, we documented an increased incidence of LV thrombus in patients with MR after AMI.     

Prospective two-dimensional echocardiographic evaluation of left ventricular thrombus and embolism after acute myocardial infarction

To determine whether two-dimensional echocardiography can identify patients with left ventricular thrombus after myocardial infarction who are prone to embolism, clinical and echocardiographic variables in 541 patients with a first infarction between 1979 and 1983 were studied prospectively. The first echocardiogram showed definite thrombus in 115 patients (Group 1, 21%) and no thrombus in 426 (Group 2, control). In Group 1, 27 patients (23%) had clinical evidence of systemic embolism related to the thrombus before referral (Group 1a) and 88 did not (Group 1b); these two groups were similar in age, gender and infarct location, but more Group 1a patients were within 1 month of the acute infarction. In both Groups 1a and 1b, the thrombus was found in apical views over asynergic zones, with no difference (p greater than 0.05) between the two groups in the size (average area from two views being 5.3 versus 4.5 cm2), type (protruding in apical views 30% versus 27%), location (apical 83% versus 86%; septal 11% versus 11%; posterior 4% versus 2%), extent of asynergy (31% versus 33%) and ejection fraction (33% versus 34%). However, the frequency of anticoagulant therapy was less (26% versus 63%, p less than 0.005), adjacent hyperkinesia greater (100% versus 49%, p less than 0.005) and thrombus mobility greater (81% versus 19%, p less than 0.005) in Group 1a than in Group 1b. Serial echocardiograms revealed a decreased size of the thrombus by 6 months in both Groups 1a and 1b, and little or no trace in 85% by 24 months. Thus, ventricular thrombus size, location and protrusion in apical views on echocardiography did not correlate with embolism. In contrast, thrombus mobility, the presence of adjacent hyperkinesia and thrombus protrusion assessed in multiple views appeared to be strong discriminators of thrombus prone to embolism. These echocardiographic features might provide a guide for the duration of anticoagulant therapy.