Rapid online quantification of left ventricular volume from real-time three-dimensional echocardiographic data.

AIMS: Determination of left ventricular (LV) volumes and ejection fraction (EF) from two-dimensional echocardiographic (2DE) images is subjective, time-consuming, and relatively inaccurate because of foreshortened views and the use of geometric assumptions. Our aims were (1) to validate a new method for rapid, online measurement of LV volumes from real-time three-dimensional echocardiographic (RT3DE) data using cardiac magnetic resonance (CMR) as the reference and (2) to compare its accuracy and reproducibility with standard 2DE measurements. METHODS AND RESULTS: CMR, 2DE, and RT3DE datasets were obtained in 50 patients. End-systolic and end-diastolic volumes (ESV and EDV) were calculated from the 2DE images using biplane method of disks. ES and ED RT3DE datasets were analysed using prototype software designed to automatically detect the endocardial surface using a deformable shell model and calculate ESV and EDV from voxel counts. 2DE and RT3DE-derived volumes were compared with CMR (linear regression, Bland-Altman analysis). In most patients, analysis of RT3DE data required <2 min per patient. RT3DE measurements correlated highly with CMR (r: 0.96, 0.97, and 0.93 for EDV, ESV, and EF, respectively) with small biases (-14 mL, -6.5 mL, -1%) and narrow limits of agreement (SD: 17 mL, 16 mL, 6.4%). 2DE measurements correlated less well with CMR (r: 0.89, 0.92, 0.86) with greater biases (-23 mL, -15 mL, 1%) and wider limits of agreement (SD: 29 mL, 24 mL, 9.5%). RT3DE resulted in lower intra-observer (EDV: 7.9 vs. 23%; ESV: 7.6 vs. 26%) and inter-observer variability (EDV: 11 vs. 26%; ESV: 13 vs. 31%). CONCLUSION: Semi-automated detection of the LV endocardial surface from RT3DE data is suitable for clinical use because it allows rapid, accurate, and reproducible measurements of LV volumes, superior to conventional 2DE methods.     

High-resolution transthoracic real-time three-dimensional echocardiography: quantitation of cardiac volumes and function using semi-automatic border detection and comparison with cardiac magnetic resonance imaging

OBJECTIVES: We sought to validate high-resolution transthoracic real-time (RT) three-dimensional echocardiography (3DE), in combination with a novel semi-automatic contour detection algorithm, for the assessment of left ventricular (LV) volumes and function in patients. BACKGROUND: Quantitative RT-3DE has been limited by impaired image quality and time-consuming manual data analysis. METHODS: Twenty-four subjects with abnormal (n = 14) or normal (n = 10) LVs were investigated. The results for end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF) obtained by manual tracing were compared with the results determined by the semi-automatic border detection algorithm. Moreover, the results of the semi-automatic method were compared with volumes and EF obtained by cardiac magnetic resonance imaging (CMRI). RESULTS: Excellent correlation coefficients (r = 0.98 to 0.99) and low variability (EDV -1.3 +/- 8.6 ml; ESV -0.2 +/- 5.4 ml; EF -0.1 +/- 2.7%; p = NS) were observed between the semi-automatically and manually assessed data. The RT-3DE data correlated highly with CMRI (r = 0.98). However, LV volumes were underestimated by RT-3DE compared with CMRI (EDV -13.6 +/- 18.9 ml, p = 0.002; ESV -12.8 +/- 20.5 ml, p = 0.005). The difference for EF was not significant between the two methods (EF 0.9 +/- 4.4%, p = NS). Observer variability was acceptable, and repeatability of the method was excellent. CONCLUSIONS: The RT-3DE, in combination with a semi-automatic contour tracing algorithm, allows accurate determination of cardiac volumes and function compared with both manual tracing and CMRI. High repeatability suggests applicability of the method for the serial follow-up of patients with cardiac disease.     

Freehand three-dimensional echocardiography with rotational scanning for measurements of left ventricular volume and ejection fraction in patients with coronary artery disease

BACKGROUND: Measurement of left ventricular (LV) volumes and ejection fraction (EF) is important in managing patients with coronary artery disease (CAD). Introduction of free-hand three-dimensional echocardiography (3DE) system which is equipped with small magnetic tracking system and average rotational geometry for LV volumes may provide easy and accurate quantification of LV systolic function in CAD patients. PURPOSE: To evaluate the feasibility and accuracy of LV volumes and EF measurement by free-hand 3DE with rotational geometry in patients with CAD. METHODS AND RESULTS: The study subjects consisted of consecutive 25 patients with CAD who were scheduled for quantitative gated single-photon emission computed tomography (QGS). LV end-diastolic volume (EDV), end-systolic volume (ESV), and EF were determined by conventional two-dimensional echocardiography (2DE), 3DE, and QGS. Three-dimensional echocardiography data acquisition and analysis were possible in 22 of 25 subjects (feasibility 88%). In this 3DE system, image acquisition time was 2 minutes, and 5 minutes were needed for off-line analysis of LV volumes and EF. Correlations and the limits of agreement between 3DE and QGS (r = 0.97, 0.0 +/- 9.1 ml for EDV, r = 0.99, 0.0 +/- 5.0 ml for ESV, and r = 0.97, 0.5 +/- 3.3% for EF, respectively) were superior to those between 2DE and QGS (r = 0.85, 12.6 +/- 26.8 ml for EDV, r = 0.85, 9.7 +/- 26.1 ml for ESV, and r = 0.90, -1.3 +/- 6.9% for EF, respectively). Inter- and intra-observer variabilities of 3DE were smaller than that of 2DE (5% vs 10%, 5% vs 10% for EDV, 6% vs 13%, 5% vs 9% for ESV, and 4% vs 11%, 4% vs 6% for EF, respectively). CONCLUSION: Three-dimensional echocardiography using magnetic tracking system and average rotational geometry offered a feasible and accurate method for quantification of LV volumes and EF in patients with CAD.     

Accuracy of three-dimensional echocardiography with unrestricted selection of imaging planes for measurement of left ventricular volumes and ejection fraction

BACKGROUND: Accurate, reproducible, noninvasive determination of left ventricular (LV) volumes and ejection fraction (EF) is important for clinical assessment, risk stratification, selection of therapy, and serial monitoring of patients with cardiovascular disease. Three-dimensional echocardiography (3DE) approaches have demonstrated significantly greater accuracy than current clinical 2DE, but the clinical utility of 3DE has been limited because of the need for substantial modifications to scanning technique (eg, all image acquisition from a single acoustic window) or cumbersome additional hardware. We describe a novel 3DE system without these limitations and its application to patients. METHODS AND RESULTS: Twenty-five patients were examined by 3DE, 2DE, and magnetic resonance imaging (MRI). The 3DE system used a magnetic scanhead tracking device, and volumes were computed with a novel deformable shell model. End-diastolic volumes and EF by MRI ranged from 96 to 375 mL and 18% to 73%, respectively. There was excellent correlation, without statistically significant differences, between MRI and 3DE for end-systolic volume (ESV) (r(2) = 0.99) and end-diastolic volume (EDV) (r(2) = 0.98), ventricular stroke volume (SV) (r(2) = 0.93), and EF (r(2) = 0.97), with standard error estimates less than 10 mL for volumes and 3% for EF. Conventional 2DE consistently underestimated volumes (EDV, P <.01; ESV, P <.01; SV, P <.05); correlations with MRI were r(2) = 0.91 for ESV, r(2) = 0.88 for EDV, r(2) = 0.62 for SV, and r(2) = 0.72 for EF. Standard error estimates ranged from 16 to 20 mL for ventricular volumes and 9% for EF. Interobserver variability was reduced 3-fold with use of 3DE. CONCLUSIONS: The novel 3DE system allows unrestricted selection and combination of acoustic windows in a single examination, improves accuracy of estimates of LV volumes and EF 3-fold compared with 2DE, and is practical for routine clinical assessment of LV size and function in patients with a wide range of cardiac pathology.     

实时三维超声心动图与磁共振对比评价左心室射血分数≥45%患者的左心室容量

目的:评价实时三维超声心动图(RT3D)测量左心室射血分数(LVEF)≥45% 成年人左心室容量的准确性和重复性.方法:选取因各种不同原因进行心脏磁共振(MRI)检查显示 LVEF ≥45%的患者37例,同时进行RT3D检查.RT3D检查采用Philips iE-33型超声心动图仪,左心室容量及左心室功能的分析通过TomTec工作站用人工描记法完成,并与MRI所得结果相比较.结果:MRI测量的左心室舒张末期容量(EDV)为:60～208.76(110.48±33.50)ml,左心室收缩末期容量(ESV)为:19～102.4(45.80±17.84 )ml,LVEF为:45.40～71.10(59.13±7.24)%.RT3D测量的EDV为:42.8～ 211.9(100.64±34.48)ml,ESV为:14.30 ～94.54(44.08 ±17.62)ml,LVEF为:35.1～73.4(56.70±7.02)%.与MRI相比,RT3D低估EDV(P＜0.01,r=0.842,y=0.867x+4.88,SEE=18.86ml),二者平均相差(-9.84±38.26) ml.RT3D同时低估ESV,二者相比差异无统计学意义(P＞0.05,r=0.846,y=0.835x+5.82,SEE=9.53 ml),二者平均相差(-1.71±19.68)ml.RT3D所测的LVEF稍小于MRI所测得的LVEF,二者相比差异有统计学意义(P＜0.05,r=0.616,y=0.597x+21.38,SEE=5.61%),平均相差(-2.42±12.5 )%.在不同观察者间及观察者自身不同时间内测量的RT3D,结果显示良好的重复性.结论:与MRI相比,RT3D测量成人患者的左心室容量及LVEF有较好的准确性和重复性.     

A comparison between QLAB and TomTec full volume reconstruction for real time three-dimensional echocardiographic quantification of left ventricular volumes

OBJECTIVES: To compare the interobserver variability and accuracy of two different real time three-dimensional echocardiography (RT3DE) analyzing programs. METHODS: Forty-one patients (mean age 56 +/- 11 years, 28 men) in sinus rhythm with a cardiomyopathy and adequate 2D image quality underwent RT3DE and magnetic resonance imaging (MRI) within one day. Off-line left ventricular (LV) volume analysis was performed with QLAB V4.2 (semiautomated border detection with biplane projections) and TomTec 4D LV analysis V2.0 (primarily manual tracking with triplane projections and semiautomated border detection). RESULTS: Excellent correlations (R(2) > 0.98) were found between MRI and RT3DE. Bland-Altman analysis revealed an underestimated LV end-diastolic volume (LV-EDV) for both TomTec (-9.4 +/- 8.7 mL) and QLAB (-16.4 +/- 13.1 ml). Also, an underestimated LV end-systolic volume (LV-ESV) for both TomTec (-4.8 +/- 9.9 mL) and QLAB (-8.5 +/- 14.2 mL) was found. LV-EDV and LV-ESV were significantly more underestimated with QLAB software. Both programs accurately calculated LV ejection fraction (LV-EF) without a bias. Interobserver variability was 6.4 +/- 7.8% vs. 12.2 +/- 10.1% for LV-EDV, 7.8 +/- 9.7% vs. 13.6 +/- 11.2% for LV-ESV, and 7.1 +/- 6.9% vs. 9.7 +/- 8.8% for LV-EF for TomTec vs. QLAB, respectively. The analysis time was shorter with QLAB (4 +/- 2 minutes vs. 6 +/- 2 minutes, P < 0.05). CONCLUSIONS: RT3DE with TomTec or QLAB software analysis provides accurate LV-EF assessment in cardiomyopathic patients with distorted LV geometry and adequate 2D image quality. However, LV volumes may be somewhat more underestimated with the current QLAB software version.     

Accuracy and reproducibility of quantitation of left ventricular function by real-time three-dimensional echocardiography versus cardiac magnetic resonance

The aim of this study was to investigate the accuracy and reproducibility of the quantification of left ventricular (LV) function by real-time 3-dimensional echocardiography (RT3DE) using current state-of-the-art hardware and software. Compared with cardiac magnetic resonance (CMR), previous generations of hardware and software for RT3DE significantly underestimated LV volumes partly because of inherent factors such as limited spatial and temporal resolution. Also, RT3DE volumes were compared with short-axis CMR data, whereas a combined short-axis and long-axis analysis is known to be superior. Twenty-four subjects (mean age 51 +/- 12 years, 17 men) in sinus rhythm and with good to excellent 2-dimensional image quality underwent RT3DE and CMR within 1 day. The acquisition of RT3DE data was done with current state-of-the-art hardware and software. Two blinded experts performed off-line LV volume analysis. Global LV volumes were determined from semiautomated border detection on the basis of endocardial speckle tracking with biplane projections using QLAB version 6.0. Volumes derived by magnetic resonance imaging were quantified from combined short-axis and long-axis series. The volume-rate on RT3DE was 33 +/- 8 Hz (range 19 to 42). Excellent correlations were found (R(2) >/= 0.97) between CMR and RT3DE for global LV end-diastolic volume, LV end-systolic volume, the LV ejection fraction, and LV phase volumes (24 phases/cardiac cycle). Bland-Altman analyses showed mean differences of -7.1 ml, -4.2 ml, 0.2%, and -5.8 ml and 95% limits of agreement of +/-19.7 ml, +/-8.3 ml, +/-6.2%, and +/-15.4 ml for global LV end-diastolic volume, LV end-systolic volume, the LV ejection fraction, and LV phase volumes, respectively. Interobserver variability was 5.2% for global LV end-diastolic volume, 6.4% for LV end-systolic volume, and 7.6% for the LV ejection fraction. In conclusion, in patients with good acoustic windows, RT3DE using state-of-the-art technology provides accurate and reproducible measurements of global LV volumes, LV volume changes over time, and the LV ejection fraction.     

Quantitation of right ventricular volumes and ejection fraction by three-dimensional echocardiography in patients: comparison with magnetic resonance imaging and radionuclide ventriculography

Three-dimensional echocardiography (3DE) provides volumetric measurements without geometric assumptions. Volume-rendered 3DE has been shown to be accurate for the measurement of right ventricular (RV) volumes in vitro and in animal studies; however, few data are available regarding its accuracy in patients. This study examined the accuracy of 3DE for quantitation of RV volumes and ejection fraction (EF) in patients, compared to magnetic resonance imaging (MRI) and radionuclide ventriculography (RNV). Twenty patients underwent MRI, gated equilibrium RNV, and 3DE using rotational acquisition from both the transesophageal and transthoracic approaches. RV volumes and EF were calculated from the 3DE data using multislice analysis (true Simpson's rule). RV volumes calculated by MRI (end-diastolic volume (EDV) 109.4 +/- 34.3 mls, end-systolic volume (ESV) 59.6 +/- 31.0 mls, and EF 47.7 +/- 17.1%) agreed closely with 3DE. For transesophageal echocardiography, EDV was 108.1 +/- 29.7 mls (r = 0.86, mean difference 1.3 +/- 17.8 mls); ESV was 62.5 +/- 23.8 mls (r = 0.85, mean difference 2.8 +/- 15.1 mls); and EF was 43.2 +/- 11.7% (r = 0.84, mean difference 4.5 +/- 9.7%). For transthoracic echocardiography, EDV was 107.7 +/- 27.5 mls (r = 0.85, mean difference 1.6 +/- 18.2 mls); ESV was 59.7 +/- 22.1 mls (r = 0.93, mean difference 3.2 +/- 19.6 mls); and EF was 45.2 +/- 11.5% (r = 0.86, mean difference 2.0 +/- 9.4%). There were close correlations, small mean differences and narrow limits of agreement between RNV-derived EF (43.4 +/- 12.1%) and both transesophageal (r = 0.95 mean difference 0.2 +/- 3.7%) and transthoracic 3DE (r = 0.95, mean difference 1.8 +/- 5.4%). Three-dimensional echocardiography is a promising new method of calculating RV volumes and EF, comparing well with MRI and RNV. The accuracy of transthoracic 3DE was comparable to that of the transesophageal approach. Three-dimensional echocardiography has the potential to be useful in the clinical assessment of RV disorders.     

Cardiac MRI assessment of left and right ventricular parameters in healthy Australian normal volunteers

Cardiac magnetic resonance imaging (MRI) is being utilised increasingly for the purposes of cardiovascular imaging. Limited data suggest a high degree of reproducibility for parameters such as left ventricular (LV) ejection fraction (EF), mass, end-diastolic and end-systolic volumes (EDV and ESV). We sought to investigate reproducibility and establish means for these parameters in a selected normal non-Aboriginal Australian population, using cardiac MRI. Sixty normal volunteers underwent cardiac MRI investigation using a 1.5 T MRI system. Steady state free precession imaging was performed with short axis cine images through the left ventricle obtained. All images were acquired with cardiac gating. Two independent observers then analysed the data set. Data were collected for assessment of left ventricular EF, EDV, ESV, mass and right ventricular volumes. Data are presented as mean+/-S.D. Total imaging time was approximately 15 min. All patients were able to complete the full protocol. Left ventricular parameters: EF 58.5+/-8.0%, LV mass 114.2+/-40.6g, EDV 117.3+/-33.4 mls and ESV 50.0+/-22.2 mls. Right ventricular parameters: EF 45.6+/-11.6%, EDV 163.5+/-52.2 mls and ESV 89.5+/-34.3 mls. Intraclass correlation coefficients for LV: EF 0.84, LV mass 0.84, EDV 0.85 and ESV 0.89. Cardiac MRI provides high quality information about cardiac function with a high level of reproducibility. Cardiac MRI parameters in a normal non-Aboriginal Australian population are provided.     

Comparison of two- and three-dimensional echocardiography with sequential magnetic resonance imaging for evaluating left ventricular volume and ejection fraction over time in patients with healed myocardial infarction

Echocardiographic follow-up of left ventricular (LV) volumes is difficult because of the test-retest variation of 2-dimensional echocardiography (2DE). We investigated whether the accuracy and reproducibility of real-time 3-dimensional echocardiography (RT3DE) would make this modality more feasible for serial follow-up of LV measurements. We performed 2DE and RT3DE and cardiac magnetic resonance imaging (MRI) in 50 patients with previous infarction and varying degrees of LV function (44 men; 61 +/- 11 years of age) at baseline and after 1-year follow-up. Images were obtained during breath-hold and measurements of LV volumes and ejection fraction were made offline. Over follow-up, end-diastolic volume decreased from 192 +/- 53 to 187 +/- 60 ml (p <0.01), end-systolic volume decreased from 104 +/- 51 to 95 +/- 53 ml (p <0.01), and ejection fraction increased from 48 +/- 12% to 51 +/- 12% (p <0.01). MRI showed that LV mass shrank from 183 +/- 39 to 182 +/- 37 g (p <0.01). The correlation between change in RT3DE and change in MRI was greater than the correlations of 2DE with MRI for measurement of end-diastolic volume (r = 0.47 vs 0.02, p <0.01), end-systolic volume (r = 0.44 vs 0.17, p <0.01), and ejection fraction (r = 0.58 vs -0.03, p <0.01). The change in end-diastolic volume between baseline and follow-up with RT3DE (-4 +/- 20, p <0.01) was similar to that with MRI but was unrecognized by 2DE (4 +/- 19, p = 0.09). There was good test-retest and inter- and intraobserver correlation within RT3DE for volumes, ejection fraction, and mass. In conclusion, if sequential measurement of LV volumes is used to guide management decisions, 3DE appears preferable to 2DE.     

Comparison of contrast agent-enhanced versus non-contrast agent-enhanced real-time three-dimensional echocardiography for analysis of left ventricular systolic function

Ultrasound contrast has shown to improve endocardial border definition. The purpose of this study was to evaluate the value of contrast agent-enhanced versus non-contrast agent-enhanced real-time 3-dimensional echocardiography (RT3DE) for the assessment of left ventricular (LV) volumes and ejection fraction. Thirty-nine unselected patients underwent RT3DE with and without SonoVue contrast agent enhancement and magnetic resonance imaging (MRI) on the same day. An image quality index was calculated by grading all 16 individual LV segments on a scale of 0 to 4: 0, not visible; 1, poor; 2, moderate; 3, good; and 4, excellent. The 3-dimensional data sets were analyzed offline using dedicated TomTec analysis software. By manual tracing, LV end-systolic volume, LV end-diastolic volume, and LV ejection fraction were calculated. After contrast agent enhancement, mean image quality index improved from 2.4 +/- 1.0 to 3.0 +/- 0.9 (p <0.001). Contrast agent-enhanced RT3DE measurements showed better correlation with MRI (LV end-diastolic volume, r = 0.97 vs 0.86; LV end-systolic volume, r = 0.96 vs 0.94; LV ejection fraction, r = 0.94 vs 0.81). The limits of agreement (Bland-Altman analysis) showed a similar bias for RT3DE images with and without contrast agent but with smaller limits of agreement for contrast agent-enhanced RT3DE. Also, inter- and intraobserver variabilities decreased. In a subgroup, patients with poor to moderate image quality showed an improvement in agreement after administration of contrast agent (+/-24.4% to +/-12.7%) to the same level as patients with moderate to good image quality without contrast agent (+/-10.4%). In conclusion, contrast agent-enhanced RT3DE is more accurate in assessment of LV function as evidenced by better correlation and narrower limits of agreement compared with MRI, as well as lower intra- and interobserver variabilities.     

Early identification of left ventricular remodelling after myocardial infarction, assessed by transthoracic 3D echocardiography.

AIMS: The usefulness of 3D echocardiography (3DE) for accurate evaluation of left ventricular (LV) remodelling after acute myocardial infarction (AMI), and early identification of remodelling in the subacute phase, was assessed. METHODS AND RESULTS: Thirty-three AMI patients (21 anterior AMIs) underwent 3DE prospectively at baseline (6+/-4 days) and at 3, 6, and 12 months post-AMI. Remodelling was defined as >20% increase in end-diastolic volume (EDV) at 6 or 12 months in relation to baseline. In patients with remodelling (n = 13) at baseline, EDV and end-systolic volume (ESV), but not ejection fraction (EF), were significantly increased compared to patients without subsequent remodelling (n = 20). At 12 months, EDV and ESV increased further and significantly, and EF was unchanged in patients with remodelling, whilst LV volumes were unchanged and EF slightly increased in patients without remodelling. Clinical, electrocardiographic, and echocardiographic variables were analysed for the early identification of LV remodelling. Of these, at baseline the 3D sphericity index (EDV divided by the volume of a sphere, the diameter of which is the LV major end-diastolic long axis) was, by far, the most predictive variable with a sensitivity, specificity, and positive and negative predictive value for a cutoff value of >0.25 of 100%, 90%, 87% and 100%, respectively. CONCLUSIONS: Three-dimensional echocardiography can differentiate patients with and without subsequent development of LV remodelling accurately and early on the basis of the 3D sphericity index, a new and highly predictive variable.     

Left ventricular volume and ejection fraction measurements by fully automated 3D echocardiography left chamber quantification software versus CMR: A systematic review and meta-analysis

BackgroundAlthough transthoracic three-dimensional echocardiography (3DE) is now recommended by guidelines for left ventricular (LV) volumetric measurements, widespread implementation has been limited due to time constraints and required expertise. We hypothesized that fully automated 3DE left chamber quantification software might provide accurate measurements, and that its application could eliminate these obstacles.MethodsTo address this hypothesis, we conducted a systematic review and meta-analysis following a search for studies that compared LV volumes and ejection fraction (EF) using fully automated 3DE software (HeartModel or Dynamic HeartModel, Philips Healthcare, Andover, MA, USA) with cardiac magnetic resonance (CMR), from 2015 to 2021. A random effects model was used to determine biases, correlations, and 95 % confidence intervals (CI) of LV end-diastolic volume (EDV), end-systolic volume (ESV), and EF. Subgroup and meta-regression analyses were performed to determine effects of moderators on the outcome.ResultsOf 12 studies (616 subjects), mean differences and 95 % CIs in EDV, ESV, and EF between fully automated 3DE software and CMR were ?19.6 mL (95 % CI; ?27.6 to ?11.5 mL), ?11.4 mL (?16.7 to ?6.2 mL), and 0.4 % (?1.1 to 2.0 %), respectively. Corresponding correlation values between the two methods were 0.91 (0.86–0.94), 0.89 (0.82–0.93), and 0.85 (0.81–0.88), respectively. Meta-regression analysis revealed that there were no effects of either publication year, type of software, or type of analysis on the outcome of LV volumetric and functional parameters except for publication year on LVESV correlation values.ConclusionsAlthough 3DE still underestimates LV volumes, the observed differences were no >20 mL. EF showed similar values to CMR. Excellent correlations between the two techniques make fully automated 3DE left chamber quantification software useful for routine clinical practice in adult population.     

Real time three-dimensional echocardiographic assessment of left ventricular function in heart failure patients: underestimation of left ventricular volume increases with the degree of dilatation

Background: Accurate quantification of left ventricular (LV) volumes and ejection fraction (EF) is of critical importance. Cardiac magnetic resonance (CMR) is considered as the reference and three-dimensional echocardiography (3DE) is an accurate method, but only few data are available in heart failure patients. We therefore sought to compare the accuracy of real time three-dimensional echocardiography (RT3DE) and two-dimensional echocardiography (2DE) for quantification of LV volumes and EF, relative to CMR imaging in an unselected population of heart failure patients. Methods and Results: We studied 24 patients (17 men, age 58 ± 15 years) with history of heart failure who underwent echocardiographic assessment of LV function (2DE, RT3DE) and CMR within a period of 24 hours. Mean LV end-diastolic volume (LVEDV) was 208 ± 109 mL (121 ± 64 mL/m(2) ) and mean LVEF was 31 ± 12.8%. 3DE data sets correlate well with CMR, particularly with respect to the EF (r: 0.8, 0.86, and 0.95; P < 0.0001 for LVEDV, LVESV, and EF, respectively) with small biases (-55 mL, -44 mL, 1.1%) and acceptable limits of agreement. RT3DE provides more accurate measurements of LVEF than 2DE (z= 2.1, P = 0.037) and lower variability. However, 3DE-derived LV volumes are significantly underestimated in patients with severe LV dilatation. In patients with LVEDV below 120 mL/m(2) , RT3DE is more accurate for volumes and EF evaluation. Conclusion: Compared with CMR, RT3DE is accurate for evaluation of EF and feasible in all our heart failure patients, at the expense of a significant underestimation of LV volumes, particularly when LVEDV is above 120 mL/m(2) .     

Quantitative assessment of left ventricular volume and ejection fraction using two-dimensional speckle tracking echocardiography

Aims: Two-dimensional speckle tracking echocardiography (2DSTE) allowsmeasurements of left ventricular (LV) volumes and LV ejectionfraction (LVEF) without manual tracings. Our goal was to determinethe accuracy of 2DSTE against real-time 3D echocardiography(RT3DE) and against cardiac magnetic resonance (CMR) imaging. Methods and results: In Protocol 1, 2DSTE data in the apical four-chamber view (iE33,Philips) and CMR images (Philips 1.5T scanner) were obtainedin 20 patients. The 2DSTE data were analysed using custom software,which automatically performed speckle tracking analysis throughoutthe cardiac cycle. LV volume curves were generated using thesingle-plane Simpson's formula, from which end-diastolic volume(LVEDV), end-systolic volume (LVESV), and LVEF were calculated.In Protocol 2, the 2DSTE and RT3DE data were acquired in 181subjects. RT3DE data sets were acquired, and LV volumes andLVEF were measured using QLab software (Philips). In Protocol1, excellent correlations were noted between the methods forLVEDV (r = 0.95), ESV (r = 0.95), and LVEF (r = 0.88). In Protocol2, LV volume waveforms suitable for analysis were obtained from2DSTE images in all subjects. The time required for analysiswas <2 min per patient. Excellent correlations were notedbetween the methods for LVEDV (r = 0.95), ESV (r = 0.97), andLVEF (r = 0.92). However, 2DSTE significantly underestimatedLVEDV, resulting in a mean of 8% underestimation in LVEF. Intra-and inter-observer variabilities of 2DSTE were 7 and 9% in LVvolume and 6 and 8% in LVEF, respectively. Conclusions: Two-dimensional speckle tracking echocardiography measurementsresulted in a small but significant underestimation of LVEDVand EF compared with RT3DE. However, the accuracy, low intra-and inter-observer variabilities and speed of analysis make2DSTE a potentially useful modality for LV functional assessmentin the routine clinical setting.     

Effects of long-term therapy with bosentan on the progression of left ventricular dysfunction and remodeling in dogs with heart failure

OBJECTIVES: In this study, we examined the effects of long-term therapy with bosentan on the progression of LV dysfunction and remodeling in dogs with moderate HF. BACKGROUND: Acute intravenous administration of bosentan, a mixed endothelin-1 type A and type B receptor antagonist, was shown to improve left ventricular (LV) function in patients and dogs with heart failure (HF). METHODS: Left ventricular dysfunction was induced by multiple, sequential intracoronary microembolizations in 14 dogs. Embolizations were discontinued when LV ejection fraction (EF) was between 30% and 40%. Dogs were randomized to three months of therapy with bosentan (30 mg/kg twice daily, n = 7) or no therapy at all (control, n = 7). RESULTS: In untreated dogs, EF decreased from 35 +/- 1% before initiating therapy to 29 +/- 1% at the end of three months of therapy (p = 0.001), and LV end-diastolic volume (EDV) and end-systolic volume (ESV) increased (EDV: 71 +/- 3 vs. 84 +/- 8 ml, p = 0.08; ESV: 46 +/- 2 vs. 60 +/- 6 ml, p = 0.03). By contrast, in dogs treated with bosentan, EF tended to increase from 34 +/- 2% before initiating therapy to 39 +/- 1% at the end of three months of therapy (p = 0.06), and EDV and ESV decreased (EDV: 75 +/- 3 vs. 71 +/- 4 ml, p = 0.05; ESV: 48 +/- 2 vs. 43 +/- 3 ml, p = 0.01). Furthermore, compared with untreated dogs, dogs treated with bosentan showed significantly less LV cardiomyocyte hypertrophy and LV volume fraction of interstitial fibrosis. CONCLUSIONS: In dogs with moderate HF, long-term therapy with bosentan prevents the progression of LV dysfunction and attenuates LV chamber remodeling. The findings support the use of mixed endothelin-1 receptor antagonists as adjuncts to the long-term treatment of HF.     

Validation of real-time three-dimensional echocardiography for quantifying left ventricular volumes in the presence of a left ventricular aneurysm: in vitro and in vivo studies

OBJECTIVES: To validate the accuracy of real-time three-dimensional echocardiography (RT3DE) for quantifying aneurysmal left ventricular (LV) volumes. BACKGROUND: Conventional two-dimensional echocardiography (2DE) has limitations when applied for quantification of LV volumes in patients with LV aneurysms. METHODS: Seven aneurysmal balloons, 15 sheep (5 with chronic LV aneurysms and 10 without LV aneurysms) during 60 different hemodynamic conditions and 29 patients (13 with chronic LV aneurysms and 16 with normal LV) underwent RT3DE and 2DE. Electromagnetic flow meters and magnetic resonance imaging (MRI) served as reference standards in the animals and in the patients, respectively. Rotated apical six-plane method with multiplanar Simpson's rule and apical biplane Simpson's rule were used to determine LV volumes by RT3DE and 2DE, respectively. RESULTS: Both RT3DE and 2DE correlated well with actual volumes for aneurysmal balloons. However, a significantly smaller mean difference (MD) was found between RT3DE and actual volumes (-7 ml for RT3DE vs. 22 ml for 2DE, p = 0.0002). Excellent correlation and agreement between RT3DE and electromagnetic flow meters for LV stroke volumes for animals with aneurysms were observed, while 2DE showed lesser correlation and agreement (r = 0.97, MD = -1.0 ml vs. r = 0.76, MD = 4.4 ml). In patients with LV aneurysms, better correlation and agreement between RT3DE and MRI for LV volumes were obtained (r = 0.99, MD = -28 ml) than between 2DE and MRI (r = 0.91, MD = -49 ml). CONCLUSIONS: For geometrically asymmetric LVs associated with ventricular aneurysms, RT3DE can accurately quantify LV volumes.     

New generation 3-dimensional echocardiography for left ventricular volumetric and functional measurements: comparison with cardiac magnetic resonance.

AIMS: Non-invasive assessment of left ventricular (LV) structure and function is important in the evaluation of cardiac patients. This study was designed to test the accuracy and reproducibility of new generation 3-dimensional echocardiography (3DE) in measuring volumetric and functional LV indices as compared with current "gold standard" of non-invasive cardiac imaging, cardiac magnetic resonance (CMR). METHODS AND RESULTS: Sixty-four subjects with good acoustic windows, including 40 cardiac patients with LV ejection fraction (EF)<45%, 14 patients with EF>45% and 10 normal volunteers underwent 3DE using a commercially available Philips Sonos 7500 scanner equipped with a matrix phase-array x4 xMATRIX transducer, and CMR on a 1.5 T Signa CV/i scanner (GE Medical Systems). Volumetric assessment was performed with analytical 4D-LV-Analysis software (TomTec) for 3DE and MRI-Mass software (Medis) for CMR. We found no significant differences in LV end-diastolic volume (EDV), end-systolic volume (ESV) and EF with excellent correlations between the indices measured using 3DE and CMR (r=0.97, r=0.98, and r=0.94, respectively). Bland-Altman analysis showed bias of 7 ml for EDV, 3 ml for ESV and -1% for EF with 3DE with corresponding limits of agreement (2SD) of 28 ml, 22 ml and 10%, respectively. Intraobserver and interobserver variabilities were for EDV: 3% and 4% (3DE) vs 2% and 2% (CMR), for ESV: 3% and 6% (3DE) vs 2% and 3% (CMR), and for EF: 4% and 4% (3DE) vs 2% and 4% (CMR), respectively. CONCLUSION: New generation 3DE provides accurate and reproducible quantification of LV volumetric and functional data in subjects with good acoustic windows as compared with CMR.     

Differences in left ventricular ejection fraction and volumes measured at rest and poststress by gated sestamibi SPECT.

BACKGROUND: Some studies suggested that the poststress left ventricle ejection fraction (LV EF) is lower than rest LV EF in patients with stress-induced ischemia. METHODS AND RESULTS: By using a 2-day protocol and 30 mCi Tc-99m sestamibi, LV EF, end-systolic volume (ESV), and end-diastolic volume (EDV) were measured with gated SPECT. Of 99 eligible patients, 91 had technically adequate studies. Poststress LV EF minus rest LV EF was defined as DeltaLV EF. DeltaEDV and DeltaESV were similarly defined. Rest and poststress LV EF (r = 0.89), EDV (r = 0.78), and ESV (r = 0.93) were highly correlated (P <.001). Rest LV EF, EDV, and ESV were not significantly different between patients with and without stress-induced ischemia. DeltaLV EF was significantly lower in patients with stress-induced ischemia (-3.5% +/- 4.5% vs -1.1% +/- 4.7%, P = .02). Mean LV EF poststress in ischemic patients was 55.0% +/- 10.5% vs 61.2% +/- 10.0% in nonischemic patients (P = .008). However, only 1 patient (3%) with ischemia had DeltaLV EF that exceeded the 95% confidence limit of DeltaLV EF for normal patients. Ischemia was significantly associated with increased DeltaEDV and DeltaESV (P < .01). CONCLUSIONS: Stress-induced ischemia is associated with poststress reduction in LV EF and increased poststress EDV and ESV. However, the effect of ischemia on the difference between poststress and rest EF measurements is modest and rarely exceeds the confidence limits in normal patients undergoing 2-day protocols. In most patients, poststress LV EF is an accurate reflection of rest LV EF.     

Effects of the angiotensin converting enzyme inhibitor enalapril on the long-term progression of left ventricular dysfunction in patients with heart failure. SOLVD Investigators.

BACKGROUND. In patients with heart failure, activation of the renin-angiotensin system is common and has been postulated to provide a stimulus for further left ventricular (LV) structural and functional derangement. We tested the hypothesis that chronic administration of the angiotensin converting enzyme (ACE) inhibitor enalapril prevents or reverses LV dilatation and systolic dysfunction among patients with depressed ejection fraction (EF) and symptomatic heart failure. METHODS AND RESULTS. We examined subsets of patients enrolled in the Treatment Trial of Studies of Left Ventricular Dysfunction (SOLVD). Fifty-six patients with mild to moderate heart failure underwent serial radionuclide ventriculograms, and 16 underwent serial left heart catheterizations, before and after randomization to enalapril (2.5-20 mg/day) or placebo. At 1 year, there were significant treatment differences in LV end-diastolic volume (EDV; p less than 0.01), end-systolic volume (ESV; p less than 0.005), and EF (p less than 0.05). These effects resulted from increases in EDV (mean +/- SD, 136 +/- 27 to 151 +/- 38 ml/m2) and ESV (103 +/- 24 to 116 +/- 24 ml/m2) in the placebo group and decreases in EDV (140 +/- 44 to 127 +/- 37 ml/m2) and ESV (106 +/- 42 to 93 +/- 37 ml/m2) in the enalapril group. Mean LVEF increased in enalapril patients from 0.25 +/- 0.07 to 0.29 +/- 0.08 (p less than 0.01). There was a significant treatment difference in LV end-diastolic pressure at 1 year (p less than 0.05), with changes paralleling those of EDV. The time constant of LV relaxation changed only in the placebo group (p less than 0.01 versus enalapril), increasing from 59.2 +/- 8.0 to 67.8 +/- 7.2 msec. Serial radionuclide studies over a period of 33 months showed increases in LV volumes only in the placebo group. Two weeks after withdrawal of enalapril, EDV and ESV increased to baseline levels but not to the higher levels observed with placebo. CONCLUSIONS. In patients with heart failure and reduced LVEF, chronic ACE inhibition with enalapril prevents progressive LV dilatation and systolic dysfunction (increased ESV). These effects probably result from a combination of altered remodeling and sustained reduction in preload and afterload.