Real-time three-dimensional fetal echocardiography--optimal imaging windows

A total of 15 fetuses were scanned using 2-D array volumetric ultrasound (US). Acquired cardiac data were converted for rendering dynamic 3-D surface views and reformatting cross-sectional views. The image usefulness was compared between the data obtained from subcostal/subxiphoid and other imaging windows; the former are usually free of acoustic shadowing. Of 60 data sets recorded, 12 (20%) were acquired through subcostal windows in 6 (40%) patients. Subcostal windows were unavailable from the remaining patients due to unfavourable fetal positions. Of the 12 sets, 6 (50%) provided the dynamic 3-D and/or cross-sectional views of either the entire fetal heart or a great portion of it for sufficient assessments of its major structures and their spatial relationships. Of 48 data sets from other windows, only 9 (19%) provided such 3-D and/or cross-sectional views; the lower rate being due to acoustic shadowing. Real-time 3-D US is a convenient method for volumetric data acquisition. Through subcostal windows, useful information about the spatial relationships between major cardiac structures can be acquired. However, to offer detailed information, considerable improvement in imaging quality is needed.     

The evaluation of single-view and multi-view fusion 3D echocardiography using image-driven segmentation and tracking

Real-time 3D echocardiography (RT3DE) promises a more objective and complete cardiac functional analysis by dynamic 3D image acquisition. Despite several efforts towards automation of left ventricle (LV) segmentation and tracking, these remain challenging research problems due to the poor-quality nature of acquired images usually containing missing anatomical information, speckle noise, and limited field-of-view (FOV). Recently, multi-view fusion 3D echocardiography has been introduced as acquiring multiple conventional single-view RT3DE images with small probe movements and fusing them together after alignment. This concept of multi-view fusion helps to improve image quality and anatomical information and extends the FOV. We now take this work further by comparing single-view and multi-view fused images in a systematic study. In order to better illustrate the differences, this work evaluates image quality and information content of single-view and multi-view fused images using image-driven LV endocardial segmentation and tracking. The image-driven methods were utilized to fully exploit image quality and anatomical information present in the image, thus purposely not including any high-level constraints like prior shape or motion knowledge in the analysis approaches. Experiments show that multi-view fused images are better suited for LV segmentation and tracking, while relatively more failures and errors were observed on single-view images.     

Can ischemia and dyssynchrony be detected during early stages of dobutamine stress echocardiography by 2-dimensional speckle tracking echocardiography?

Strain and strain rate (SR) measured with 2-dimensional speckle tracking echocardiography (2-D STE) can quantitatively assess myocardial function. Our aim was to evaluate whether we could detect abnormalities in strain, strain rate, and dyssynchrony by applying 2-D STE in patients with severe coronary artery disease during early stages of dobutamine stress echocardiography. Thirty-four patients with angiographically documented severe 3-vessel coronary artery disease and preserved left ventricular ejection fraction were compared with 42 control patients without evidence of coronary artery disease. Circumferential and longitudinal strain, SR, and left ventricular synchrony using standard deviation (SD) of time to systolic peak strain and SR were analyzed with 2-D STE at rest and at intermediate doses of dobutamine stress echocardiography. Compared with control subjects, patients with coronary artery disease showed lower circumferential SR [?1.42 (0.34) s^?1 vs ?1.64 (0.34) s^?1; P < .02] and significantly lower longitudinal strain [?15.41 % (3.52 %) vs ?19.37 % (3.21 %); P < .001] and SR [?0.91 (0.18) s^?1 vs ?1.19 (0.24) s^?1; P < .001] at intermediate doses; these values were also compromised at peak dose. The SD of longitudinal time to systolic peak strain at intermediate dose was significantly greater in patients with coronary artery disease than in control patients [37.89 (12.32) vs 27.21 (10.86); P < .001]. The 2-D STE-derived strain and SR detected myocardial dysfunction and asynchrony in patients with coronary artery disease during intermediate doses of dobutamine stress, with minimal changes in regional wall motion abnormalities at this stage.     

左室心肌质量三维超声心动图与MRI测值的对比研究

目的　以磁共振显像技术为对照标准 ,探讨动态三维超声技术测量左室心肌质量的准确性。方法　 33例患者分别应用经胸 M-型、二维、三维超声心动图检查和磁共振检查测定左室心肌质量。结果　以磁共振测量的心肌质量为标准 ,M-型、二维和三维超声心动图测定的心肌质量与 MRI法测值的相关系数分别为0 .90、 0 .91和 0 .98(P均 <0 .0 5 ) ;配对 t检验表明 ,M-型超声法测定值明显高于 MRI心肌质量测定值 [(2 0 8.91± 6 4 .18) g vs(182 .97± 5 5 .0 8) g,SEE=12 .2 6 g,P<0 .0 5 ],而二维超声面积 -长度法 [(181.0 2± 5 9.6 7) g]和三维超声心动图法心肌质量测定值 [(181.83± 5 5 .4 7) g]与 MRI法测定值之间则无显著性差异 (P均 >0 .0 5 ) ,SEE分别为 8.91g、 4 .2 2 g。结论　以磁共振显像为对照标准 ,三维超声测量心肌质量的准确性显著高于 M-型超声和二维超声心动图技术     

3-D Contrast-Enhanced Ultrasound Fusion Imaging: A New Technique to Evaluate the Ablative Margin of Radiofrequency Ablation for Hepatocellular Carcinoma

To investigate the feasibility of assessing the ablative margin (AM) of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) with 3-D contrast-enhanced ultrasound fusion imaging (3-DCEUS-FI), pre- and post-RFA 3-DCEUS images of 84 patients with HCC were fused for two radiologists to independently assess the AMs. The success rate, duration and influencing factors for registration; inter-observer agreement for AM classification; and local tumor progression (LTP) rate were evaluated. The success rate of the automatic registration (AR), which was completed within 4–12 s, was 57.1% (48/84). The duration and success rate of the interactive registration (IR) were 4.2 ± 1.8 min and 91.7% (77/84) for radiologist A and 4.8 ± 2.1 min and 91.7% (77/84) for radiologist B, respectively. The multivariate analysis demonstrated that the pre-RFA image quality, number of vessels (≥3 mm) and presence of acoustic shadow were independent factors for AR (p < 0.05), while the number of vessels was an independent factor for IR (p = 0.001). The agreement between observers was excellent (kappa = 0.914). LTP rate was significantly higher for AMs <5 mm than for AMs ≥5 mm (p = 0.024). Quantitatively evaluating the AM immediately after RFA for HCC with 3-DCEUS-FI was feasible.     

Mechanical deformation in adult patients with unrepaired aortic coarctation

Aortic coarctation is a congenital heart disease that causes an increased left ventricular afterload, resulting in increased systolic parietal tension, compensatory hypertrophy, and left ventricular systolic and diastolic dysfunction. The speckle tracking is a new echocardiographic technique that allows the detection of subclinic left ventricular systolic dysfunction. The aim of this study was to detect early left ventricular dysfunction using mechanical deformation by echocardiography in adults with un-repaired aortic coarctation. A total of 41 subjects were studied, 20 patients with aortic coarctation and 21 control subjects, 21 women (51.2%), with an average age of 30?±?10 years. All patients with aortic coarctation had systemic arterial hypertension (p?<?0.001). Seventy percent (14/20) of the patients had bicuspid aortic valve. Statistically significance (p?<?0.005) were found in left ventricular mass index, E/e ratio, pulmonary artery systolic pressure and peak velocity and maximum gradient of the aortic valve. The global longitudinal deformation of the left ventricle in patients with aortic coarctation was significative decreased, p?<?0.001. The ejection fraction and the global longitudinal deformation of the left ventricle were significantly lower in patients with aortic coarctation compared to the control group, p?<?0.003, p?<?0.001, respectively. The subgroup of patients with coarctation and left ventricular ejection fraction?<?55% had a marked decrease in global longitudinal strain (??15.9?±?4%). The radial deformation was increased in patients with aortic coarctation and showed a trend to be significant (r?=?0.421; p?<?0.06). A significant negative correlation was observed between the global longitudinal deformation and left ventricular mass index (r?=?0.54; p?=?0.01) in the aortic coarctation group. The patients with aortic coarctation and left ventricular hypertrophy had marked reduction of left ventricular global longitudinal deformation (??16%, p?<?0.05). In our study patients with normal left ventricular ejection fraction had abnormal global longitudinal deformation and also the increased left ventricular mass was related with a decreased left ventricular global longitudinal deformation as a sign of subclinical systolic dysfunction.     

Hand-carried echocardiography for assessment of left ventricular filling and ejection fraction in the surgical intensive care unit

Purpose

To better define the reliability of left ventricular ejection fraction (LVEF) and left ventricular filling, as determined by either hand-carried ultrasound (HCU) or formal transthoracic echocardiography (TTE), in the critically ill surgical patient.

Materials and Methods

Prospective cross-sectional study of 80 surgical intensive care unit patients with concomitant (<30 minutes apart) formal TTE and clinician-performed cardiac HCU. Visual estimates of LVEF and left ventricular filling (“underfilled” vs “normally filled”) were recorded, both by clinicians performing HCU and fellowship-trained echocardiographers.

Results

Bland-Altman plot analysis of LVEF estimates revealed good interobserver agreement between HCU and formal TTE (% LVEF mean bias, −2.2; with 95% limits of agreement, ±22.1). This was similar to agreement between independent echocardiography observers (% LVEF mean bias, 1.3; with 95% limits of agreement, ±21.0). However, assessments of left ventricular filling demonstrated only fair to moderate interobserver agreement (κ = 0.22-0.40). Of note, a greater percentage of the 5 standard acoustic windows were obtainable using formal TTE (72% vs 56%).

Conclusions

Formal TTE offers no advantage over HCU for determination of LVEF in critically ill surgical patients, even though the former allows for a more complete examination. However, estimations of left ventricular filling only demonstrate fair to moderate interrater agreement and thus should be interpreted with care when used as markers of volume responsiveness.     

Quantification of Left Ventricular Size and Function Using Contrast-Enhanced Real-Time 3D Imaging with Power Modulation: Comparison with Cardiac MRI

In patients with optimal images, real-time 3-D echocardiography (RT3DE) allows accurate evaluation of left ventricular (LV) volumes and ejection fraction (EF). However, in patients with poor acoustic windows, lower correlations were reported despite the use of contrast. We hypothesized that power modulation (PM) RT3DE imaging that uses low mechanical indices and provides uniform LV opacification could overcome this problem. Accordingly, we sought to: (i) Test the feasibility of quantification of LV volumes and EF from contrast-enhanced (CE) PM RT3DE images, (ii) validate this technique against cardiac magnetic resonance (CMR) reference and (iii) test its clinical value by quantifying the improvement in accuracy and reproducibility. We studied 20 patients who underwent CMR, harmonic nonenhanced RT3DE and CE PM RT3DE imaging on the same day. All images were analyzed to obtain end-systolic and end-diastolic LV volumes (EDV, ESV) and calculate EF. To determine the reproducibility of each RT3DE technique, imaging was repeated in the same setting by a second sonographer. In addition, patients were divided according to the quality of their RT3DE images into two groups, for which agreement with CMR and reproducibility were calculated separately. CE PM RT3DE imaging improved the accuracy of EDV, ESV and EF measurements in patients with poor acoustic windows without significantly affecting those in patients with optimal images. In addition, CE PM RT3DE imaging improved the reproducibility of the measurements, as reflected by a twofold decrease in intermeasurement variability. Importantly, the variability in CE PM RT3DE–derived volumes and EF was under 10%, irrespective of image quality. This methodology may become the new standard for LV size and function, which will be particularly important in patients with poor acoustic windows or contraindications to CMR.     

Multiview fusion 3-D echocardiography: improving the information and quality of real-time 3-D echocardiography

The advent of real-time 3-D echocardiography (RT3DE) promised dynamic 3-D image acquisition with the potential of a more objective and complete functional analysis. In spite of that, 2-D echocardiography remains the backbone of echocardiography imaging in current clinical practice, with RT3DE mainly used for clinical research. The uptake of RT3DE has been slow because of missing anatomic information, limited field-of-view (FOV) and tedious analysis procedures. This paper presents multiview fusion 3D echocardiography, where multiple images with complementary information are acquired from different probe positions. These multiple images are subsequently aligned and fused together for preserving salient structures in a single, multiview fused image. A novel and simple wavelet-based fusion algorithm is proposed that exploits the low- and high-frequency separation capability of the wavelet analysis. The results obtained show that the proposed multiview fusion considerably improves the contrast (31.1%), contrast-to-noise ratio (46.7%), signal-to-noise ratio (44.7%) and anatomic features (12%) in 3-D echocardiography, and enlarges the FOV (28.2%). This indicates that multiview fusion substantially enhances the image quality and information.     

Non-invasive Evaluation of Right Ventricular Function with Real-Time 3-D Echocardiography

The aim of this study was to evaluate the accuracy and feasibility of real-time 3-D echocardiography (3-DE) in assessing right ventricular (RV) systolic function. A latex balloon was inserted into the right ventricle of 20 freshly harvested pig hearts which were then passively driven by a pulsatile pump apparatus. The RV global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS) and RV ejection fraction (RVEF), derived from 3-DE, as well as the RVEF obtained from 2-D echocardiography (2-DE) were quantified at different stroke volumes (30–70 mL) and compared with sonomicrometry data. In all comparisons, 3-D GLS, GCS, GAS, 2-D RVEF and 3-D RVEF exhibited strong correlations with sonomicrometry data (r = 0.89, 0.79, 0.74, 0.80, and 0.93, respectively; all p values < 0.001). Bland–Altman analyses revealed slight overestimations of echo-derived GLS, GCS, 2-DE RVEF and 3-DE RVEF compared with sonomicrometry values (bias = 1.55, 2.72, 3.59 and 2.21, respectively). Furthermore, there is better agreement among GLS, 3-D RVEF and the sonomicrometry values than between GCS and 2-D RVEF. Real-time 3-DE is more feasible and accurate for assessing RV function than 2-DE. GLS is a potential alternative parameter for quantifying RV systolic function.     

Right ventricular function in grown-up patients after correction of congenital right heart disease

Aims

We investigated whether a correlation exists between biomarkers of the neurohumoral system and clinical markers in grown-up patients with congenital heart disease (GUCH) and right ventricular function.

Methods and results

Prospective, cross-sectional, multicenter study of 104 GUCH patients (median) 16?years (range 6?C43?years) after corrective surgery with RV pressure and/or volume overload and 54 healthy controls. Clinical, functional, and laboratory parameters were assessed. Natriuretic peptide levels were significantly increased in GUCH patients (NTproBNP 101 vs. 25?pg/ml, p?<?0.001), but we observed no differences in norepinephrine, aldosterone, angiotensin II and Endothelin-1 levels. NTproBNP correlated significantly with clinical markers such as NYHA classification, prolonged QRS duration and reduced exercise capacity (VO₂ peak) (all p?<?0.001), as well as self-reported quality of life (p?<?0.001). MRI and echocardiography derived RV volumes were elevated and ejection fraction reduced in the patients (both p?<?0.001). Tissue Doppler parameter showed significantly restricted ventricular longitudinal systolic function (longitudinal tricuspid valve movement, 1.7 vs. 2.3?cm, p?<?0.001), suggesting stiffness and reduced RV compliance.

Conclusion

In conclusion, grown-up patients with congenital right heart disease NTproBNP correlates well with various clinical markers of RV failure, such as prolongation of QRS duration, exercise capacity, echocardiography and MRI parameters, and quality of life.     

Left ventricular wall motion analysis using real-time three-dimensional ultrasound

This study tested the ability of real-time 3-D (RT 3-D) echocardiography to detect and delineate regions of abnormal contraction (akinesia or dyskinesia) in a canine model of regional myocardial injury and to develop methods to simplify injury assessments. Closed chest RT 3-D scans were obtained and regional left ventricular (LV) contractile function was assessed in nine animals at baseline and after myocardial cryoinjury with a 1-cm cryoprobe. Evaluation of contractile function was based on radial shortening of LV chamber cross-sections at multiple levels. Radial length changes were analyzed using color-coded circumferential maps of the LV. Seven sets of motion maps demonstrated new areas of poorly contracting myocardium in the cryoinjured region relative to baseline. Two sets of data were excluded due to insufficient LV visualization. Motion maps derived from RT 3-D echo have the ability to detect and localize regions of abnormal LV wall motion.     

Three-Dimensional Echocardiography-Derived Non-Invasive Right Ventricular Pressure-Volume Analysis

In patients with pulmonary hypertension, repeated evaluations of right ventricular (RV) function are still required for clinical decision making, but the invasive nature of current pressure-volume analysis makes conducting regular follow-ups in a clinical setting infeasible. We enrolled 12 patients with pulmonary arterial hypertension (PAH) and 10 with pulmonary venous hypertension (PVH) May 2016–October 2016. All patients underwent a clinically indicated right heart catheterization (RHC), from which the yielded right ventricular pressure recordings were conjugated with RV volume by 3-D echocardiography to generate a pressure-volume loop. A continuous-wave Doppler envelope of tricuspid regurgitation was transformed into a pressure gradient recording by the simplified Bernoulli equation, and then a systolic pressure gradient-volume (PG-V) diagram was generated from similar methods. The area enclosed by the pressure-volume loop was calculated to represent semi-invasive right ventricular stroke work (RVSW_RHC). The area between the PG-V diagram and x-axis was calculated to estimate non-invasive RVSW (RVSW_echo). Patients with PAH have higher RV pressure, lower pulmonary arterial wedge pressure and larger RV volume that was contributed by the dilation of RV mid-cavity minor dimension. We found no significant difference of traditional parameters between these two groups, but RVSW values were significantly higher in PAH patients. The RVSW values of these two methods were significantly correlated by the equation RVSW_echo = 0.8447 RVSW_RHC + 129.38 (R² = 0.9151, p < 0.001). The linearity remained satisfactory in both groups. We conclude that a PG-V diagram is a reliable method to estimate RVSW and to depict pathophysiological status.     

Segmentation of real-time three-dimensional ultrasound for quantification of ventricular function: a clinical study on right and left ventricles

Among screening modalities, echocardiography is the fastest, least expensive and least invasive method for imaging the heart. A new generation of three-dimensional (3-D) ultrasound (US) technology has been developed with real-time 3-D (RT3-D) matrix phased-array transducers. These transducers allow interactive 3-D visualization of cardiac anatomy and fast ventricular volume estimation without tomographic interpolation as required with earlier 3-D US acquisition systems. However, real-time acquisition speed is performed at the cost of decreasing spatial resolution, leading to echocardiographic data with poor definition of anatomical structures and high levels of speckle noise. The poor quality of the US signal has limited the acceptance of RT3-D US technology in clinical practice, despite the wealth of information acquired by this system, far greater than with any other existing echocardiography screening modality. We present, in this work, a clinical study for segmentation of right and left ventricular volumes using RT3-D US. A preprocessing of the volumetric data sets was performed using spatiotemporal brushlet denoising, as presented in previous articles Two deformable-model segmentation methods were implemented in 2-D using a parametric formulation and in 3-D using an implicit formulation with a level set implementation for extraction of endocardial surfaces on denoised RT3-D US data. A complete and rigorous validation of the segmentation methods was carried out for quantification of left and right ventricular volumes and ejection fraction, including comparison of measurements with cardiac magnetic resonance imaging as the reference. Results for volume and ejection fraction measurements report good performance of quantification of cardiac function on RT3-D data compared with magnetic resonance imaging with better performance of semiautomatic segmentation methods than with manual tracing on the US data.     

Analysis of the quantitative improvements in resting echocardiographic image sharpness through the use of contrast enhanced echocardiography

Contrast enhanced echocardiography (CEE) is a technique for the improvement of suboptimal echocardiographic studies. While commonly performed at selected institutions, its value has only been shown qualitatively, and to this point no study has been directed at establishing a quantitative improvement in image quality compared with non-contrast enhanced echocardiography (non-CEE). The purpose of this study was to quantitatively measure the effect of contrast on the quality of images obtained during non-CEE versus CEE. Thirty consecutive patients underwent CEE. In all subjects a non-CEE was obtained prior to administering any contrast, allowing for a direct comparison and an internal control group. Sharpness of the septal, apical and lateral myocardial walls in the apical 4-chamber view was calculated with and without contrast. Three signal intensity levels were obtained for each wall then averaged to compare the images with and without contrast for a statistically significant difference in sharpness. Quantitative analysis showed a significant difference in sharpness between CEE and non-CEE in the left ventricular septal myocardial wall, p < 0.01. A more drastic significant increase in image sharpness was observed between non-CEE and CEE in the apical and lateral left ventricular myocardial walls, both p < 0.000001. CEE significantly increases the sharpness at all left ventricular myocardial walls thus allowing higher quality images with presumably more accurate diagnosis of regional wall motion abnormalities, left ventricular endocardial border detection, left ventricular dimensions, ejection fraction and apical pathology.     

Three-dimensional echocardiographic measurement of left ventricular mass: Comparison with magnetic resonance imaging and two-dimensional echocardiographic determinations in man

This study was performed to compare a novel three-dimensional echocardiography (3DE) system to clinical two-dimensional echocardiography (2DE) and magnetic resonance imaging (MRI) for determination of left ventricular mass (LVM) in humans. LVM is an independent predictor of cardiac morbidity and mortality. Echocardiography is the most widely used clinical method for assessment of LVM, as it is non-invasive, portable and relatively inexpensive. However, when measuring LVM, 2DE is limited by assumptions about ventricular shape which do not affect 3D echo. Methods: A total of 25 unselected patients underwent 3DE, 2DE and MRI. Three-dimensional echo used a magnetic scanhead tracker allowing unrestricted selection and combination of images from multiple acoustic windows. Mass by quantitative 2DE was assessed using seven different geometric formulas. Results: LVM by MRI ranged from 91 to 316 g. There was excellent agreement between 3DE and MRI (r = 0.99, SEE = 6.9 g). Quantitative 2D methods correlated well with but underestimated MRI (r = 0.84–0.92) with SEEs over threefold greater (22.5–30.8 g). Interobserver variation was 7.6% for 3DE vs. 17.7% for 2DE. Conclusions: LVM in humans can be measured accurately, relative to MRI, by transthoracic 3D echo using magnetic tracking. Compared to 2D echo, 3D echocardiography significantly improves accuracy and reproducibility.     

The risk of non-sustained ventricular tachycardia after percutaneous alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy

Background

Percutaneous alcohol septal ablation (ASA) becomes an alternative option of treatment for symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM). The procedure relieves left ventricular outflow tract obstruction, but produces a myocardial scar in patients who already have a substrate for life-threatening ventricular arrhythmia.

Objectives

To examine the effect of ASA on the occurrence of non-sustained ventricular tachycardia (nsVT) on 24 h ambulatory Holter monitoring in HOCM patients.

Methods

Sixty-one consecutive patients (34 males, mean age 48 years), who underwent ASA between 1997 and 2003 were analyzed. Holter recordings were performed in each patient before and after ablation.

Results

Follow-up ranged from 60 to 125 months (median 116 months). The mean number of Holter recordings per patient was 2.7 (range 1–11) before and 8.3 (range 2–23) after ASA (p < 0.001). Non-sustained ventricular tachycardia occurred in 14 patients before and 27 patients after ASA (23 vs. 44%, p = 0.01). The percentage of Holter recordings with nsVT before and after ablation was similar (14.5 vs. 15.7%, p = 0.56, respectively). No difference was observed between the number of nsVT per Holter recording before and after ablation (0.21 vs. 0.24%, p = 0.65, respectively). The percentage of patients with nsVT after ASA was comparable to the proportion of patients with nsVT in a control group consisting of 705 patients with hypertrophic cardiomyopathy under follow-up at our institution (44.3 vs. 43.2%, p = 0.91). There was no significant difference in percentage of Holter recordings with nsVT with respect to sex, amount of alcohol used during ASA, peak creatine phosphokinase level, and gradient reduction at rest.

Conclusion

Alcohol septal ablation affected neither the percentage of Holter recordings with nsVT nor the number of nsVT episodes per Holter recording among HOCM patients.     

The subxiphoid view cannot replace the apical view for transthoracic echocardiographic assessment of hemodynamic status

Introduction

This prospective study aimed to assess whether use of the subxiphoid acoustic window in transthoracic echocardiography (TTE) can be an accurate alternative in the absence of an apical view to assess hemodynamic parameters.

Methods

This prospective study took place in a teaching hospital medical ICU. Over a 4-month period, TTE was performed in patients admitted for more than 24 hours. Two operators rated the quality of parasternal, apical, and subxiphoid acoustic windows as Excellent, Good, Acceptable, Poor, or No image. In the subpopulation presenting adequate (rated as acceptable or higher) apical and subxiphoid views, we compared the left ventricular ejection fraction (LVEF), the ratio between right and left ventricular end-diastolic areas (RVEDA/LVEDA), the ratio between early and late mitral inflow on pulsed Doppler (E/A ratio), the aortic velocity time integral (Ao VTI), and the ratio between early mitral inflow and displacement of the mitral annulus on tissue Doppler imaging (E/Ea ratio).

Results

An adequate apical view was obtained in 80%, and an adequate subxiphoid view was obtained in 63% of the 107 patients included. Only 5% of patients presented an adequate subxiphoid view without an adequate apical view. In the subpopulation of patients with adequate apical and subxiphoid windows (n = 65), LVEF, E/A, and RVEDA/LVEDA were comparable on both views, and were strongly correlated (r > 0.80) with acceptable biases and precision. However, the Ao VTI and the E/Ea ratio were lower on the subxiphoid view than on the apical view (18 ± 5 versus 16 ± 5 cm and 9.6 ± 4.6 versus 7.6 ± 4 cm, respectively, P = 0.001 for both).

Conclusions

An adequate TTE subxiphoid window was obtained in fewer than two thirds of ICU patients. In addition to the classic indication for the subxiphoid window to study the vena cava and pericardium, this view can be used to study right and left ventricular morphology and function, but does not provide accurate hemodynamic Doppler information. ICU echocardiographers should therefore record both apical and subxiphoid views to assess comprehensively the cardiac function and hemodynamic status.     

Optimisation of coronary vascular territorial 3D echocardiographic strain imaging using computed tomography: a feasibility study using image fusion

Current echocardiographic assessments of coronary vascular territories use the 17-segment model and are based on general assumptions of coronary vascular distribution. Fusion of 3D echocardiography (3DE) with multidetector computed tomography (MDCT) derived coronary anatomy may provide a more accurate assessment of left ventricular (LV) territorial function. We aimed to test the feasibility of MDCT and 3DE fusion and to compare territorial longitudinal strain (LS) using the 17-segment model and a MDCT-guided vascular model. 28 patients underwent 320-slice MDCT and transthoracic 3DE on the same day followed by invasive coronary angiography. MDCT (Aquilion ONE, ViSION Edition, Toshiba Medical Systems) and 3DE apical full-volume images (Artida, Toshiba Medical Systems) were fused offline using a dedicated workstation (prototype fusion software, Toshiba Medical Systems). 3DE/MDCT image alignment was assessed by 3 readers using a 4-point scale. Territorial LS was assessed using the 17-segment model and the MDCT-guided vascular model in territories supplied by significantly stenotic and non-significantly stenotic vessels. Successful 3DE/MDCT image alignment was obtained in 86 and 93?% of cases for reader one, and reader two and three, respectively. Fair agreement on the quality of automatic image alignment (intra-class correlation?=?0.40) and the success of manual image alignment (Fleiss’ Kappa?=?0.40) among the readers was found. In territories supplied by non-significantly stenotic left circumflex arteries, LS was significantly higher in the MDCT-guided vascular model compared to the 17-segment model: ?15.00?±?7.17 (mean?±?standard deviation) versus ?11.87?±?4.09 (p?<?0.05). Fusion of MDCT and 3DE is feasible and provides physiologically meaningful displays of myocardial function.     

Longitudinal systolic ventricular interaction in pediatric and young adult patients with TOF: a cardiac magnetic resonance and M-mode echocardiographic study

Aim of this prospective study was to evaluate longitudinal systolic left ventricular (LV)–right ventricular (RV) interaction using M-mode compared to magnetic resonance imaging (MRI) data in 146 pediatric and adults with operated tetralogy of Fallot (TOF). We determined biventricular measures of longitudinal M-mode echocardiography [i.e. tricuspid annular plane systolic excursion (TAPSE); the mitral annular plane systolic excursion (MAPSE)] compared to longitudinal function parameters using MRI. M-mode data were compared to established normal z-score values. We found a good correlation between MAPSE and LVEF values (r = 0.788; p < 0.001). Correlations between MRI derived MAPSE and M-mode guided MAPSE (r = 0.879, p < 0.001), and between MRI derived TAPSE and M-mode guided TAPSE were significant (r = 0.780, p < 0.001). While the LVEF was normal in patients with a normal RVEF, the LVEF was decreased in patients with significantly reduced RVEF. Patients with a significantly dilated RV (RVEDVi > 150 ml/m²) showed a significantly reduced mean MAPSE of 1.30 ± 0.26 cm. LV longitudinal function decreases below ?2 SD of normal MAPSE z-score values after a mean of 22 postoperative years. Our data confirm progressive adverse RV–LV interaction in the long-term follow-up of TOF. We show that simple M-mode measurement of the longitudinal LV function (i.e. MAPSE) is a sufficient surrogate for estimation of LVEF. Therefore determination of the MAPSE is a helpful additional tool for LV systolic function assessment late after TOF repair.