Three-dimensional color Doppler: a clinical study in patients with mitral regurgitation.
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OBJECTIVES: The purpose of this study was to assess the clinical feasibility of three-dimensional (3D) reconstruction of color Doppler signals in patients with mitral regurgitation. BACKGROUND: Two-dimensional (2D) color Doppler has limited value in visualizing and quantifying asymmetric mitral regurgitation. Clinical studies on 3D reconstruction of Doppler signals in original color coding have not yet been performed in patients. We have developed a new procedure for 3D reconstruction of color Doppler. METHODS: We studied 58 patients by transesophageal 3D echocardiography. The jet area was assessed by planimetry and the jet volumes by 3D Doppler. The regurgitant fractions, the volumes, and the angiographic degree of mitral regurgitation were assessed in 28 patients with central jets and compared with those of 30 patients with eccentric jets. RESULTS: In all patients, jet areas and jet volumes significantly correlated with the angiographic grading (r = 0.73 and r = 0.90), the regurgitant fraction (r = 0.68 and r = 0.80) and the regurgitant volume (r = 0.66 and r = 0.90). In patients with central jets, significant correlations were found between jet area and angiography (r = 0.86), regurgitant fraction (r = 0.64) and regurgitant volume (r = 0.78). No significant correlations were found between jet area and angiography (r = 0.53), regurgitant fraction (r = 0.52) and regurgitant volume (r = 0.53) in the group of patients with eccentric jets. In contrast, jet volumes significantly correlated with angiography (r = 0.90), regurgitant fraction (r = 0.75) and regurgitant volume (r = 0.88) in the group of patients with eccentric jets. CONCLUSIONS: Three-dimensional Doppler revealed new images of the complex jet geometry. In addition, jet volumes, assessed by an automated voxel count, independent of manual planimetry or subjective estimation, showed that 3D Doppler is also capable of quantifying asymmetric jets. (+info)
Three-dimensional Doppler. Techniques and clinical applications.
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AIMS: Colour Doppler is the most widely used technique for assessing valve disease, but eccentric regurgitant jets cannot be visualized and measured by conventional 2D techniques. We have developed a new procedure for three-dimensional (3D) reconstruction of colour Doppler signals. METHODS AND RESULTS: Fifty patients with mitral regurgitation underwent transoesophageal echocardiography and 3D acquisition. The severity of mitral regurgitation was assessed by angiography and the regurgitant volumes were measured by pulsed Doppler. The jet areas were calculated by planimetry from conventional colour Doppler; the jet volumes were obtained by 3D Doppler. A higher degree of mitral regurgitation was found in the patients with eccentric jets. While jet areas showed poor correlation with regurgitant volumes (r = 0.61), jet volumes correlated significantly with regurgitant volumes (r = 0.93; P < 0.001). While jet areas failed to identify patients with different grades of regurgitation, jet volumes could so discriminate. CONCLUSIONS: 3D Doppler revealed new patterns of regurgitant flow and allowed a more accurate semiquantitative assessment of complex asymmetrical regurgitant jets. Three-dimensional colour Doppler has a great potential for becoming a reference method for the assessment of patients with heart valve disease. (+info)
Real-time three-dimensional echocardiography acquires data as a volume rather than as a series of planar images, thereby obviating cardiac or respiratory gating and limiting artifacts generated by random motion. This study was undertaken to evaluate the feasibility of using real-time three-dimensional echocardiography to evaluate fetal cardiac anatomy and function. Ten human fetuses were evaluated in utero, four of whom had congenital heart disease. Freehand transabdominal scanning was performed on each pregnant woman using a real-time three-dimensional echocardiography system. Four volume clips at 20 volumes/s of duration 1.5 s each were obtained on each fetal heart and stored for off-line analysis. Data were displayed immediately as a series of four simultaneous planes, with the ability for the observer to manipulate the position of each plane within the acquired volume data set. Cardiac motion could be slowed, stopped, or viewed at its original speed. Most structures and views, as well as cardiac function, could be visualized consistently. Abnormal structures could be detected readily. Off-line analysis was rapid and easy. We conclude that fetal real-time three-dimensional echocardiography is a feasible, facile, and rapid new technique. (+info)
Importance of imaging method over imaging modality in noninvasive determination of left ventricular volumes and ejection fraction: assessment by two- and three-dimensional echocardiography and magnetic resonance imaging.
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OBJECTIVES: This study sought to determine the concordance between biplane and volumetric echocardiography and magnetic resonance imaging (MRI) strategies and their impact on the classification of patients according to left ventricular (LV) ejection fraction (EF) (LVEF). BACKGROUND: Transthoracic echocardiography and MRI are noninvasive imaging modalities well suited for serial evaluation of LV volume and LVEF. Despite the accuracy and reproducibility of volumetric methods, quantitative biplane methods are commonly used, as they minimize both scanning and analysis times. METHODS: Thirty-five adult subjects, including 25 patients with dilated cardiomyopathies, were evaluated by biplane and volumetric (cardiac short-axis stack) cine MRI and by biplane and volumetric (three-dimensional) transthoracic echocardiography. Left ventricular volume, LVEF and LV function categories (LVEF > or =55%, >35% to <55% and < or =35%) were then determined. RESULTS: Biplane echocardiography underestimated LV volume with respect to the other three strategies (p < 0.01). There were no significant differences (p > 0.05) between any of the strategies for quantitative LVEF. Volumetric MRI and volumetric echocardiography differed by a single functional category for 2 patients (8%). Six to 11 patients (24% to 44%) differed when comparing biplane and volumetric methods. Ten patients (40%) changed their functional status when biplane MRI and biplane echocardiography were compared; this comparison also revealed the greatest mean absolute difference in estimates of EF for those subjects whose EF functional category had changed. CONCLUSIONS: Volumetric MRI and volumetric echocardiographic measures of LV volume and LVEF agree well and give similar results when used to stratify patients with dilated cardiomyopathy according to systolic function. Agreement is poor between biplane and volumetric methods and worse between biplane methods, which assigned 40% of patients to different categories according to LVEF. The choice of imaging method (volumetric or biplane) has a greater impact on the results than does the choice of imaging modality (echocardiography or MRI) when measuring LV volume and systolic function. (+info)
Left atrial volume assessed by transthoracic three dimensional echocardiography and magnetic resonance imaging: dynamic changes during the heart cycle in children.
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OBJECTIVE: To assess the dynamic changes in left atrial volume by transthoracic three dimensional echocardiography and compare the results with those obtained by magnetic resonance imaging (MRI). DESIGN AND PATIENTS: 30 healthy children (15 boys and 15 girls, aged 8 to 13 years) underwent examination by three dimensional echocardiography and MRI. METHODS: Three dimensional echocardiography of the left atrium was performed using rotational acquisition of planes at 18 degrees intervals from the parasternal window with ECG gating and without respiratory gating. Volume estimation by MRI was performed with a slice thickness of 4-8 mm and ECG triggering during breath holding in deep inspiration. A left atrial time-volume curve was reconstructed in each child. RESULTS: Left atrial maximum and minimum volumes averaged 24.0 ml/m(2) and 7. 6 ml/m(2) by three dimensional echocardiography, and 22.1 ml/m(2) and 11.9 ml/m(2) by MRI. The greater left atrial minimum volume in the latter was at least in part a result of breath holding. Dynamic changes in left atrial volume during the heart cycle were detectable by both methods. The higher temporal resolution of three dimensional echocardiography allowed a more precise evaluation of different phases. CONCLUSIONS: Three dimensional echocardiography and MRI were both useful methods for studying the physiological volume changes in the left atrium in children. These methods may be used for further study of the systolic and diastolic function of the heart. (+info)
Transcatheter closure of multiple atrial septal defects. Initial results and value of two- and three-dimensional transoesophageal echocardiography.
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AIMS: To examine the feasibility of transcatheter closure of multiple atrial septal defects using two Amplatzer devices simultaneously and to describe the importance and the role of two- and three-dimensional transoesophageal echocardiography in the selection and closure of such defects. METHODS: Twenty-two patients with more than one atrial septal defect underwent an attempt at transcatheter closure of their atrial septal defects at a mean+/-SD age of 30. 8+/-18.6 years (range 3.7-65.9 years) and mean weight of 56.6+/-25.5 kg (range 12.9-99 kg) using two Amplatzer devices implanted simultaneously via two separate delivery systems. During catheterization, two dimensional transoesophageal echocardiography was performed in all but one patient, during and after transcatheter closure, while three dimensional transoesophageal echocardiography was performed in six patients before and after transcatheter closure. RESULTS: Forty-four devices were deployed in all patients to close 45 defects (one patient with three defects closed by two devices). Two dimensional transoesophageal echocardiography was helpful in selection and in guiding correct deployment of the devices. The mean size of the larger defect, as measured by transoesophageal echocardiography was 12.8+/-5.9 mm and the mean size of the smaller defect was 6.6+/-3.0 mm. The mean size of the larger devices was 15+/-7.5 mm, and 8.4+/-3.7 mm for the smaller. Three dimensional transoesophageal echocardiography provided superior imaging and demonstrated the number, shape and the surrounding structures of the atrial septal defects in one single view. The median fluoroscopy time was 28.7 min. Device embolization with successful catheter retrieval occurred in one patient. Forty-four devices were evaluated by colour Doppler transoesophageal echocardiography immediately after the catheterization with a successful closure rate of 97.7%. On follow-up colour Doppler transthoracic echocardiography demonstrated successful closure in 97.5% at 3 months. CONCLUSIONS: The use of more than one Amplatzer septal occluder to close multiple atrial septal defects is safe and effective. The use of two- and three-dimensional transoesophageal echocardiography provided useful information for transcatheter closure of multiple atrial septal defects using two devices. Three-dimensional transoesophageal echocardiography enhanced our ability to image and understand the spatial relationship of the atrial septal defect anatomy. (+info)
Dynamic morphology of the secundum atrial septal defect evaluated by three dimensional transoesophageal echocardiography.
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OBJECTIVE: To define by three dimensional echocardiography the pattern and potential determinants of contraction of a secundum atrial septal defect through the cardiac cycle, and to evaluate the possibility of using cross sectional transthoracic and transoesophageal imaging to assess the dynamic nature of the defect. DESIGN: Three dimensional echocardiography was performed using a multiplane transoesophageal probe on 50 patients with a secundum atrial septal defect (median age 9.8 years). Nine patients were excluded because of poor images or morphological features that precluded defect measurement. In 41 cases, defect area, long and short axis length, and distance of the attenuated anterior rim were measured in their largest and smallest dimensions. RESULTS: Defect area changed significantly through the cardiac cycle (mean change 61%, p < 0.0001; range 17% to 86%). The defect contracted symmetrically and was not related to patient age, defect size, heart rate, Qp/Qs ratio, the presence of an aneurysmal atrial septum, or attenuated anterior rim. In all cases with an attenuated anterior rim (n = 13), the length of the rim significantly decreased (p = 0. 001) during atrial systole. Dynamic changes measured by either transthoracic or transoesophageal cross sectional images did not correlate with those obtained by three dimensional imaging. CONCLUSIONS: Three dimensional echocardiography shows dynamic features of defects in the atrial septum. This information may lead to an improved understanding of the pathophysiology of atrial shunting. (+info)
Design of a new surgical approach for ventricular remodeling to relieve ischemic mitral regurgitation: insights from 3-dimensional echocardiography.
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BACKGROUND: Mechanistic insights from 3D echocardiography (echo) can guide therapy. In particular, ischemic mitral regurgitation (MR) is difficult to repair, often persisting despite annular reduction. We hypothesized that (1) in a chronic infarct model of progressive MR, regurgitation parallels 3D changes in the geometry of mitral leaflet attachments, causing increased leaflet tethering and restricting closure; therefore, (2) MR can be reduced by restoring tethering geometry toward normal, using a new ventricular remodeling approach based on 3D echo findings. METHODS AND RESULTS: We studied 10 sheep by 3D echo just after circumflex marginal ligation and 8 weeks later. MR, at first absent, became moderate as the left ventricle (LV) dilated and the papillary muscles shifted posteriorly and mediolaterally, increasing the leaflet tethering distance from papillary muscle tips to the anterior mitral annulus (P<0.0001). To counteract these shifts, the LV was remodeled by plication of the infarct region to reduce myocardial bulging, without muscle excision or cardiopulmonary bypass. Immediately and up to 2 months after plication, MR was reduced to trace-to-mild as tethering distance was decreased (P<0.0001). LV ejection fraction, global LV end-systolic volume, and mitral annular area were relatively unchanged. By multiple regression, the only independent predictor of MR was tethering distance (r(2)=0.81). CONCLUSIONS: Ischemic MR in this model relates strongly to changes in 3D mitral leaflet attachment geometry. These insights from quantitative 3D echo allowed us to design an effective LV remodeling approach to reduce MR by relieving tethering. (+info)