Parasternal Short-axis View Research Articles

Feasibility of Echocardiographic Estimation of Pulmonary Artery Stiffness in Horses

Pulmonary artery stiffness (PAS) is an index of pulmonary artery elasticity that permits to evaluate the pulmonary vascular bed in humans. It can early detect an increase in pulmonary artery stiffness as a consequence of remodeling of the vessel wall caused by chronic pulmonary and congenital heart diseases. This remodeling can occur also in horses with chronic respiratory diseases. Thus, PAS could be a useful echocardiographic parameter also in horses. However, in literature, there are no studies regarding PAS in horses. The aim of this study is to evaluate the feasibility of PAS in horses. Fifteen healthy horses were included in this prospective study. Maximal frequency shift and acceleration time were measured from the pulsed-wave Doppler trace of the pulmonary artery flow, obtained from the right parasternal short-axis view at the level of the pulmonary artery, and then PAS was calculated as the ratio of Maximal frequency shift to acceleration time. The low variability assessed for intra- and inter-observer variability, day-to-day variability and image acquisition variability suggests that PAS can be measured consistently in horses. Further studies could be useful to assess the clinical usefulness of PAS in unhealthy horses, such as those affected by chronic respiratory diseases.

Cardiac Strain Imaging Using Multi-Perspective Ultrafast Ultrasound

The heart is a complex organ with a high level of deformation occurring in different directions. Ultrasound imaging has proven to be a valuable tool to quantify these deformations. However, strain is not always measured accurately in vital parts of the heart when only using a single probe, even at a high frame rate, because of the anisotropic spatial resolution and contrast. Therefore, a multi-perspective ultrafast ultrasound (US) strain imaging method was developed, aiming at investigating improvements in strain while operating two probes at different relative angles. In an ex-vivo experiment of a beating porcine heart, parasternal short axis views of the left ventricle (LV) were acquired by two phased array probes with different relative angles (30°–75°) at a frame rate of 170 frames per second (FPS). A fully automatic registration algorithm was developed to register the image datasets for all cases. Next, radio frequency (RF) based strain imaging was performed. Axial displacements were compounded based on the unit axial vectors of the dual probes to improve motion tracking and strain estimation. After performing multi-perspective strain imaging, compounded radial and circumferential strain both improve compared to single probe strain imaging. While increasing the inter-probe angle from 30° to 75°, the mean tracking error (ME), mean drift error (MDE) and strain variability (SV) decreased, and signal-to-noise ratio (SNRe) increased for both strain components. For the largest angle (75°), large reductions in ME (−42%), MDE (−50%) and SV (−48%) were observed. The SNRe increased by 253 and 39% for radial and circumferential strain, respectively, and strain curves revealed less noise for each region. In summary, a multi-perspective ultrafast US strain imaging method was introduced to improve cardiac strain estimation in an ex-vivo beating porcine heart setup.

Coronary Artery Origins Pattern in Pediatric Patients with Right-Left Fusion Bicuspid Aortic Valve.

Bicuspid aortic valve (BAV) is a common congenital heart defect associated with coronary artery (CA) variants, including higher incidence of left CA dominance and shorter left main CA length. We observed by transthoracic echocardiography that left and right CA origins appear closer together in pediatric patients with right-left fusion (R/L) BAV compared to patients with trileaflet aortic valves. We sought to objectively confirm this observation. A retrospective review of pediatric echocardiograms with R/L BAV at a single institution (12/2010-11/2018) was performed. The 'coronary angle' was defined as the angle between the left and right coronary artery origins in the parasternal short axis view relative to the center of the aortic valve orifice. Values were compared to age-matched controls. Patients with inadequate images, anomalous coronary origins, or predefined significant congenital heart defects were excluded. We compared 191 R/L BAV patients (64% male) to 136 controls (57% male). Coronary angle was significantly more acute in R/L BAV than in controls (117.9° ± 16.7° vs 139.0° ± 10.1°, p < 0.0001). This was independent of age and gender. The difference persisted when BAV patients with abnormal aortic annulus/root diameters were removed from analysis (119.5° ± 15.1° vs 139.0° ± 10.1°, p < 0.0001). CA origins are closer together in R/L BAV independent of age, gender, or annulus/root size. This new anatomical description may aid in the diagnosis of subtle ('forme fruste') R/L BAV, assist in interventional planning, and improve understanding of the relationship between BAV and CA development.

Fully automated quantification of cardiac chamber and function assessment in 2-D echocardiography: clinical feasibility of deep learning-based algorithms

We aimed to compare the segmentation performance of the current prominent deep learning (DL) algorithms with ground-truth segmentations and to validate the reproducibility of the manually created 2D echocardiographic four cardiac chamber ground-truth annotation. Recently emerged DL based fully-automated chamber segmentation and function assessment methods have shown great potential for future application in aiding image acquisition, quantification, and suggestion for diagnosis. However, the performance of current DL algorithms have not previously been compared with each other. In addition, the reproducibility of ground-truth annotations which are the basis of these algorithms have not yet been fully validated. We retrospectively enrolled 500 consecutive patients who underwent transthoracic echocardiogram (TTE) from December 2019 to December 2020. Simple U-net, Res-U-net, and Dense-U-net algorithms were compared for the segmentation performances and clinical indices such as left atrial volume (LAV), left ventricular end diastolic volume (LVEDV), left ventricular end systolic volume (LVESV), LV mass, and ejection fraction (EF) were evaluated. The inter- and intra-observer variability analysis was performed by two expert sonographers for a randomly selected echocardiographic view in 100 patients (apical 2-chamber, apical 4-chamber, and parasternal short axis views). The overall performance of all DL methods was excellent [average dice similarity coefficient (DSC) 0.91 to 0.95 and average Intersection over union (IOU) 0.83 to 0.90], with the exception of LV wall area on PSAX view (average DSC of 0.83, IOU 0.72). In addition, there were no significant difference in clinical indices between ground truth and automated DL measurements. For inter- and intra-observer variability analysis, the overall intra observer reproducibility was excellent: LAV (ICC = 0.995), LVEDV (ICC = 0.996), LVESV (ICC = 0.997), LV mass (ICC = 0.991) and EF (ICC = 0.984). The inter-observer reproducibility was slightly lower as compared to intraobserver agreement: LAV (ICC = 0.976), LVEDV (ICC = 0.982), LVESV (ICC = 0.970), LV mass (ICC = 0.971), and EF (ICC = 0.899). The three current prominent DL-based fully automated methods are able to reliably perform four-chamber segmentation and quantification of clinical indices. Furthermore, we were able to validate the four cardiac chamber ground-truth annotation and demonstrate an overall excellent reproducibility, but still with some degree of inter-observer variability.

The value of echocardiographic measurement of epicardial adipose tissue in heart failure patients.

AimsEpicardial adipose tissue (EAT) is increasingly recognized as an important factor in the pathophysiology of heart failure (HF). Cardiac magnetic resonance (CMR) imaging is the gold‐standard imaging modality to evaluate EAT size, but in contrast to echocardiography, CMR is costly and not widely available. We investigated EAT thickness on echocardiography in relation to EAT volume on CMR, and we assessed the agreement between observers for measuring echocardiographic EAT.Methods and resultsPatients with HF and left ventricular ejection fraction >40% were enrolled. All patients underwent CMR imaging and transthoracic‐echocardiography. EAT volume was quantified on CMR short‐axis cine‐stacks. Echocardiographic EAT thickness was measured on parasternal long‐axis and short‐axis views. Linear regression analyses were used to assess the association between EAT volume on CMR and EAT thickness on echocardiography. Intraclass correlation coefficient (ICC) was used to assess the interobserver agreement as well as the intraobserver agreement. EAT on CMR and echocardiography was evaluated in 117 patients (mean age 71 ± 10 years, 49% women and mean left ventricular ejection fraction 54 ± 7%). Mean EAT volume on CMR was 202 ± 64 mL and ranged from 80 to 373 mL. Mean EAT thickness on echocardiography was 3.8 ± 1.5 mm and ranged from 1.7 to 10.2 mm. EAT volume on CMR and EAT thickness on echocardiography were significantly correlated (junior‐observer: r = 0.62, P < 0.001, senior‐observer: r = 0.33, P < 0.001), and up to one‐third of the variance in EAT volume was explained by EAT thickness (R 2 = 0.38, P < 0.001). The interobserver agreement between junior and senior observers for measuring echocardiographic EAT was modest [ICC, 0.65 (95% confidence interval (CI) 0.47–0.77], whereas the intraobserver agreement was good (ICC 0.98, 95% CI 0.84–0.99).ConclusionsThere was a modest correlation between EAT volume on CMR and EAT thickness on echocardiography. Limited agreement between junior and senior observers for measuring echocardiographic EAT was observed. EAT thickness on echocardiography is limited in estimating EAT volume.

A case of double‐chambered right ventricle due to cap‐like fibrous tissue and aberrant chordal insertion of tricuspid valve in adult

A double-chambered right ventricle is a rare congenital heart disease where an anomalous structure divides the right ventricle into two cavities. A 78-year-old man with dyspnea was referred to our institution for a double-chambered right ventricle (DCRV) and ventricular septal defect (VSD). Echocardiography showed normal left ventricular function, right ventricular hypertrophy, and mild tricuspid regurgitation. On parasternal short-axis views, color-flow Doppler studies showed a mosaic pattern through the stenotic right ventricular outflow tract (RVOT). Cardiac catheterization showed a 122 mmHg pressure gradient between the high-pressure chamber and the low-pressure chamber of the RVOT. Computed tomography showed a cap-like structure consisting of fibrous tissue, with moderate stenosis, which divided the right ventricle into two cavities. The aberrant tendinous chords supporting the anterior leaflet of the tricuspid valve were found inserted into the anterior wall of the RV (Figure 1). Resection of the cap-like fibrous tissue and abnormal muscle (Figure 2), detachment of aberrant tendinous chords of the tricuspid valve, closure of VSD by direct suture, and tricuspid valve plasty (TVP) were performed. TVP was achieved using an artificial chordae replacement with expanded polytetrafluoroethylene (CV-5) suture and a 32-mm Physio Tricuspid annuloplasty ring (Edwards Lifeline). Postoperative echocardiography revealed no RVOT pressure gradient and a normal right ventricular pressure of 21 mmHg. In conclusion, we report a rare case of DCRV secondary to a cap-like structure fibrous tissue with anomalous chordal insertion of a tricuspid valve leaflet.

Moderna Vaccine Induced Recurrent Myopericarditis

COVID-19 mRNA vaccine-related myocarditis and myopericarditis is a rare complication, with the US Centers for disease Control and Prevention reporting 4.2 per million females aged 12-29 years, dropping to 1.0 per million over 30, and exceptionally rare is recurrent myopericarditis requiring immunosuppressive therapy. We report a case of a 51-year-old female with no significant medical history presented to the emergency department with pleuritic chest pain, and progressive breathlessness 9 days after her first Moderna vaccine. Electrocardiography revealed widespread ST segment elevation with PR depression in the inferior leads. Her inflammatory markers were elevated with a C- reactive protein of 263. Transthoracic echocardiography revealed a moderate circumferential pericardial effusion with a maximum of 1.8cm adjacent to the lateral wall of the left ventricle in the parasternal short axis view and no evidence of tamponade physiology. The patient did not show initial response to anti-inflammatory therapy, and was commenced on steroid therapy, and subsequently immunosuppressive therapy, namely azathioprine, to manage disease activity. This case brings to light a rare but significant side effect of mRNA vaccine, and whilst this case should not impede vaccination efforts, it highlights that whilst the majority of patients get transient self-limiting myocardial inflammation, rare cases of prolonged myopericarditis may occur which may require prolonged immunosuppression.

Classification of Echocardiographic Standard Views Using a Hybrid Attention-based Approach

The determination of the probe viewpoint forms an essential step in automatic echocardiographic image analysis. However, classifying echocardiograms at the video level is complicated, and previous observations concluded that the most significant challenge lies in distinguishing among the various adjacent views. To this end, we propose an ECHO-Attention architecture consisting of two parts. We first design an ECHO-ACTION block, which efficiently encodes Spatio-temporal features, channel-wise features, and motion features. Then, we can insert this block into existing ResNet architectures, combined with a self-attention module to ensure its task-related focus, to form an effective ECHO-Attention network. The experimental results are confirmed on a dataset of 2693 videos acquired from 267 patients that trained cardiologist has manually labeled. Our methods provide a comparable classification performance (overall accuracy of 94.81%) on the entire video sample and achieved significant improvements on the classification of anatomically similar views (precision 88.65% and 81.70% for parasternal short-axis apical view and parasternal short-axis papillary view on 30-frame clips, respectively).

OR4. Agreement between Transthoracic Echocardiography and Surgical Measurements of the Tricuspid Annulus Diameter

Abstract Aims The tricuspid annulus dilatation is an indication for tricuspid repair concomitant with mitral surgery. The distance between anteroseptal and anteroposterior commissure represents the direction of dilatation provided by surgical measurements. However, none of the standard views of two-dimensional transthoracic echocardiography (2D-TTE) intersect that plane and there is still a lack of study regarding the tricuspid annulus measurements by three-dimensional transthoracic echocardiography (3D-TTE). Therefore, this study aims to determine the agreement between the tricuspid annulus diameter measurement by transthoracic echocardiography and surgical measurement. Methods and Results 40 patients were included. Measurements of tricuspid annulus diameter by 2D-TTE and 3D-TTE were performed before surgery in parasternal right ventricle inflow (PRVI), parasternal short axis (PSAX), apical 4-chambers (A4C), and multiplanar analysis 3D-TTE views. Surgical measurements were performed during surgery. Agreement between the echocardiography and surgical measurements was analyzed using Bland-Altman and intraclass correlation analysis. Mean difference ± standard deviation (limits of agreement) and ICC of PRVI 2D-TTE vs surgical measurement were 1.35±5.02 mm (-8.48 - 11.18 mm), ICC 0.89, p &amp;lt; 0.001; PSAX 2D-TTE vs surgical measurement were 1.35±5.23 mm (-8.90 - 11.60 mm), ICC 0.88, p &amp;lt; 0.001; A4C 2D-TTE vs surgical measurement were 1.33±3.69 mm (-5.91 - 8.56 mm), ICC 0.93, p &amp;lt; 0.001; septolateral diameter 3D-TTE vs surgical measurements were 1.42±4.41 mm, (-7.22 - 10.06 mm), ICC 0.90, p &amp;lt; 0.001; anteroposterior diameter 3D-TTE vs surgical measurements were -2.695±7.43 mm (- 17.26 - 11.87 mm), ICC 0.68, p &amp;lt; 0.001. Conclusion A4C 2D-TTE and septolateral diameter 3D-TTE measurement have an excellent agreement with surgical measurement.

Abstract 10345: Video-Based Deep Learning Model for Automated Assessment of Ejection Fraction in Pediatric Patients

Introduction: Echocardiographic assessment of left ventricular (LV) systolic function by ejection fraction (EF) is crucial for diagnosis and monitoring in pediatric patients. EF requires manual tracing of the LV but measurement reproducibility is affected by diverse phenotypes, image quality, and operator skill. We sought to train a deep learning model (EchoNet-Peds) on a pediatric-specific video dataset to automatically segment the LV and estimate EF by 5/6 Area Length (AL) using two common views, the apical 4 chamber (A4C) and parasternal short axis (PSAX). Methods: EchoNet-Peds evaluated raw A4C and PSAX videos to segment the LV and predict the EF from the A4C and PSAX views. Eighty percent of the dataset was used for algorithm training, 10% for validation, and 10% for testing. We used the training set to predict the EF by AL, determined hyperparameters from the validation set, and reported results using 10-fold cross-validation on the test set. Results: The dataset included 1923 children (43% female) with 4400 echocardiogram studies. EFs ranged from 10% to 81% (61% ± 10.1) and ages from 0 to 18 years (10 ± 5.4 years). EchoNet-Peds achieved Dice Similarity Coefficients of 0.901 (0.895 - 0.907) and 0.887 (0.879 - 0.895) for segmenting the LV in A4C and PSAX views respectively. The A4C view predicts an EF by AL with an R2 of 0.73 (0.67 - 0.77) and the PSAX view predicts an R2 of 0.74 (0.70 - 0.77). Combining both predictions results in an overall R2 of 0.78 (0.74 - 0.81). The model performs well when stratified by sex, age, and body surface area (BSA), and improves in younger patients and lower BSA (Figure 1 b-d). Conclusions: EchoNet-Peds is the first demonstration that AI trained on a pediatric-specific dataset utilizing multiple views can accurately segment the LV and predict EF. The automated functionality of EchoNet-Peds can be used for real-time assessment of cardiac function despite pediatric heterogeneity.

An Abnormal Echocardiogram and Telemetry Tracing in a Late Preterm Infant.

An Abnormal Echocardiogram and Telemetry Tracing in a Late Preterm Infant.

Echocardiographic assessment of radial right ventricular function in heart transplant recipients.

AimsRight ventricular (RV) allograft dysfunction is present in half of all heart transplant (HT) recipients. Non‐invasive assessment of RV function in the setting of rejection is not well described. We outline an echocardiographic technique, short‐axis fractional area change (SAXFAC), to evaluate RV function in the HT population and correlate this with the grade of pathologic rejection.Methods and resultsWe retrospectively reviewed the electronic medical records of 110 people who received a HT between 1 January 2015 and 29 February 2020 and had no evidence of rejection. One hundred eighty‐two transthoracic echocardiograms (TTEs) completed up to 1 year from the date of transplantation were analysed for the target acoustic window, the parasternal mid‐ventricular short‐axis view. Sixty‐one TTEs from 23 healthy transplants were deemed appropriate for SAXFAC determination. Thirty‐three organ recipients with at least grade 1R allograft rejection were also identified, and their TTEs screened for SAXFAC analysis. Two expert readers independently calculated SAXFAC as follows: RV end‐diastolic area minus end‐systolic area divided by end‐diastolic area. Using commercially available software (Epsilon, Ann Arbor, Michigan), we quantified RV radial strain, longitudinal strain, and apical fractional area change (FAC). Twenty‐eight transplant recipients with grade 0R or 1R rejection and nine patients with clinically significant rejection completed the study analysis. SAXFAC demonstrated significant variability in the entire population with an inverse relationship to severity of allograft rejection (P ≤ 0.01). Radial strain and FAC were also associated with clinically significant rejection (P ≤ 0.01).ConclusionsShort‐axis fractional area change is a simple two‐dimensional technique to assess RV function in HT recipients and showed no significant inter‐observer variability. In our small, single‐centre, retrospective case series, lower SAXFAC values were associated with clinically significant allograft rejection. The small sample size and infrequent occurrence of rejection make our observations hypothesis‐generating only. We advocate dedicated RV SAXFAC imaging planes be included when assessing allograft function.

Lean or obese, the epicardial fat thickness is increased in diabetics of south India – is it a south Indian paradox?

Abstract Type 2 Diabetes Mellitus (T2DM) is considered a Coronary Artery Disease (CAD) risk equivalent (1) Increased epicardial fat (EFT) thickness is one hypothesis contributing to the disproportionate CV morbidity and mortality in T2DM (2). Studies have shown, EFT was higher in patients T2DM and high BMI compared to the non diabetic group. (3). The aim of our study was to determine if T2DM patients had an increased EFT thickness even when their BMI was normal or low and whether there was a relation between the T2DM duration and the EFT thickness. Study cohort consisted of 260 patients, who underwent coronary angiography (CAG) for suspected CAD. All patients underwent detailed history, examination, routine biochemistry, HBA1c, Anthropometric measurements such as weight, height, waist circumference and BMI. Transthoracic ECHO assessment of EFT was done one day prior to CAG using the ECHO unit with a 3.6MHz transducer. The EFT thickness was measured as the echo-free space between the myocardium and visceral pericardium on the right ventricular free wall in end-systole in the parasternal long and short-axis views for 3 cardiac cycles. CAG was performed in the fasting state, using the Judkins' technique, by the femoral or radial artery approach. The severity of CAD was assessed by modified Gensini scoring system. The collected data were analysed with IBM.SPSS statistics software. Of the 260 patients 90 (73.1%) were males and 70 (26.9%) were females. In this study, the average value for normal EFT was 5.2mm in the control group (HBA1c &amp;lt;7) and anything more than 6 was taken as abnormal. Patients were divided into 4 groups based on their HbA1c levels viz Group A (HbA1c &amp;lt;7), Group B (HbA1c 7–9), Group C (HbA1c 9.1–12) and Group D (HbA1c &amp;gt;12). The EFT increased with increasing HbA1c levels and the correlation was statistically significant P value 0.0005. There was no gender differences in EFT in our study. EFT was higher when the T2DM duration was &amp;gt;5 yrs which was statistically significant. p value 0.0005 (Table 1). There have been no reports of the correlation between the duration of DM and EFT in literature to the best of our knowledge.There was a strong correlation between HbA1c and EFT and the severity of the coronary lesions which was statistically significant. There was no correlation between the BMI and EFT or CAD (Figure 1) and the EFT was increased even in non obese diabetics. This may be due to the fact that EFT is a part of visceral obesity whereas BMI is a measure of generalised obesity. Our study showed a linear correlation between EFT thickness, HBA1c, duration of T2DM irrespective of BMI values confirming the recent thinking that regional fat depots such as EFT are of greater importance as a CAD risk factor than overall adiposity as was previously considered. ECHO measured EFT can be used to raise the clinical suspicion of CAD in asymptomatic diabetics and being non invasive can also be used for followup. Funding Acknowledgement Type of funding sources: None. Table 1. Relation of T2DM duration with EFTFigure 1. Relation of BMI to EFT

Classification of Echocardiogram View using A Convolutional Neural Network

The standard views in echocardiography capture distinct slices of the heart which can be used to assess cardiac function. Determining the view of a given echocardiogram is the first step for analysis. To automate this step, a deep network of the ResNet-18 architecture was used to classify between six standard views. The network parameters were pre-trained with the ImageNet database and prediction quality was assessed with a visualization tool known as gradient-weighted class activation mapping (Grad-CAM). The network was able to distinguish between three parasternal short axis views and three apical views to ~99\% accuracy. 10-fold cross validation showed a 97\%-98\% accuracy for the apical view subcategories (which included apical two-, three-, and four- chamber views). Grad-CAM images of these views highlighted features that were similar to those used by experts in manual classification. Parasternal short axis subcategories (which included apex level, mitral valve level, and papillary muscle level) had accuracies of 54\%-73\%. Grad-CAM images illustrate that the network classifies most parasternal short axis views as belonging to the papillary muscle level. Likely more images and incorporating time-dependent features would increase the parasternal short axis view accuracy. Overall, a convolutional neural network can be used to reliably classify echocardiogram views.

Adoptability and accuracy of point-of-care ultrasound in screening for valvular heart disease in the primary care setting.

Despite continued efforts, a majority of patients with valvular heart disease (VHD) remain undiagnosed and untreated. This study aimed to assess the adoptability and accuracy of point-of-care handheld echocardiographic assessments (POCE) in the primary care setting. Eleven previously untrained primary care providers were trained to use the Vscan Extend (GE, WI) POCE to assess VHD, left ventricular function (LVEF), and major extra-cardiac findings. Their assessments were compared to those of three blinded expert readers. A total of 175 patients underwent POCE assessments which were evaluated using Kappa statistics (κ) together with their estimated standard error, p value, and 95% CI bounds. Each patient had a mean of 3.3 ± 1.1 (±SD) assessments performed. Identical or nearly identical agreement between previously untrained primary providers and expert readers was evident for the diagnosis of tricuspid regurgitation, mitral regurgitation, pericardial effusion, and volume status. These agreements were strongest in apical long axis (κ=1, p < 0.001) and parasternal long and short axis views (κ > =0.82 p < 0.001), though agreement remained robust in apical 4-chamber views (κ ≥ 0.76). The agreements in LVEF assessment were identical in the apical long axis view (κ=1, p < 0.001) and robust in the remaining 3 views (κ > =0.66, p < 0.001). The assessments of aortic stenosis (parasternal/long, κ=0.42, and parasternal/short, κ=0.47, both p < 0.001) were weak in their agreement. Compared to expert echocardiography readers, the untrained providers' use of POCE for VHD shows high user adoptability and diagnostic accuracies in the primary care setting.

Ultrasonographic study of the right coronary artery in performance horses

Historically, echocardiography has focused on the assessment of cardiac dimensions and índices of cardiac function. However, when referred to ultrasonographic coronary arteries characterisation in the horse, information is scarce. The purpose of this study was to describe the right coronary artery in both long and short axis and to analyse its variability between horses with different levels of performance. Sixty healthy horses were included in the study. The animals were eventing horses at different levels of performance and were allocated into two groups according to their athletic level. The internal lumen diameter and the area of the right coronary artery (RCA) were measured in the right parasternal long and short axis views in the 3rd and 4th intercostal space respectively, during systole and diastole. The results were compared between groups using the analysis of variance (ANOVA) and Student's t-test. The correlation between the physiological parameters and the RCA was assessed using the Pearson correlation coefficient. Statistically significant differences were found when the RCA internal diameter was assessed between groups in both short and long axis. There were no statistically significant differences intra-group when short and long axis measurements were compared between each other. A positive correlation was observed between RCA and age, height, left atrium diameter, aortic valve diameter, sinus of Valsalva diameter, and aorta diameter. In conclusion, the level of training might affect the ultrasound measurement of the RCA in sport horses. Non-invasive echocardiography can be used to consistently assess the size of the right coronary artery in athletic horses in both short and long axis.

Evaluation of strain averaging area and strain estimation errors in a spheroidal left ventricular model using synthetic image data and speckle tracking

BackgroundIn majority of studies on speckle tracking echocardiography (STE) the strain estimates are averaged over large areas of the left ventricle. This may impair the diagnostic capability of the STE in the case of e.g. local changes of the cardiac contractility. This work attempts to evaluate, how far one can reduce the averaging area, without sacrificing the estimation accuracy that could be important from the clinical point of view.MethodsSynthetic radio frequency (RF) data of a spheroidal left ventricular (LV) model were generated using FIELD II package and meshes obtained from finite element method (FEM) simulation. The apical two chamber (A2C) view and the mid parasternal short axis view (pSAXM) were simulated. The sector encompassed the entire cross-section (full view) of the LV model or its part (partial view). The wall segments obtained according to the American Heart Association (AHA17) were divided into subsegments of area decreasing down to 3 mm2. Longitudinal, circumferential and radial strain estimates, obtained using a hierarchical block-matching method, were averaged over these subsegments. Estimation accuracy was assessed using several error measures, making most use of the prediction of the maximal relative error of the strain estimate obtained using the FEM derived reference. Three limits of this predicted maximal error were studied, namely 16.7%, 33% and 66%. The smallest averaging area resulting in the strain estimation error below one of these limits was considered the smallest allowable averaging area (SAAA) of the strain estimation.ResultsIn all AHA17 segments, using the A2C projection, the SAAA ensuring maximal longitudinal strain estimates error below 33% was below 3 mm2, except for the segment no 17 where it was above 278 mm2. The SAAA ensuring maximal circumferential strain estimates error below 33% depended on the AHA17 segment position within the imaging sector and view type and ranged from below 3–287 mm2. The SAAA ensuring maximal radial strain estimates error below 33% obtained in the pSAXM projection was not less than 287 mm2. The SAAA values obtained using other maximal error limits differ from SAAA values observed for the 33% error limit only in limited number of cases. SAAA decreased when using maximal error limit equal to 66% in these cases. The use of the partial view (narrow sector) resulted in a decrease of the SAAA.ConclusionsThe SAAA varies strongly between strain components. In a vast part of the LV model wall in the A2C view the longitudinal strain could be estimated using SAAA below 3 mm2, which is smaller than the averaging area currently used in clinic, thus with a higher resolution. The SAAA of the circumferential strain estimation strongly depends on the position of the region of interest and the parameters of the acquisition. The SAAA of the radial strain estimation takes the highest values. The use of a narrow sector could increase diagnostic capabilities of 2D STE.

Bicuspid Aortic Valve in Infants, Children, and Adolescents: A Review for Primary Care Providers.

1. Talha Niaz, MBBS* 2. Jonathan N. Johnson, MD*,† 3. Frank Cetta, MD*,† 4. Timothy M. Olson, MD*,† 5. Donald J. Hagler, MD*,† 1. *Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, and 2. †Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN * Abbreviations: AHA : : American Heart Association BAV : : bicuspid aortic valve TTE : : transthoracic echocardiography Bicuspid aortic valve is the most common congenital heart defect in children, adolescents, and adults. Primary care providers play an important role in screening, referral, and follow-up of these patients and should be aware of the family screening guidelines, sports participation recommendations, and periodic follow-up requirements for adequate surveillance of the complications that arise from bicuspid aortic valve. After reading this article, readers should be able to: 1. Describe the epidemiology and anatomy of bicuspid aortic valve (BAV). 2. Understand the clinical presentation and diagnosis of BAV in infants, children, and adolescents. 3. Identify the various complications of BAV disease. 4. Discuss the management and follow-up requirements for BAV. 5. Analyze the family screening and sports participation guidelines for patients with BAV. Bicuspid aortic valve (BAV) is the most common congenital heart defect in children, adolescents, and adults. (1) It is a heterogeneous disease that affects both the aortic valve and the aorta. It can lead to many complications, including aortic valve stenosis, regurgitation, or endocarditis. (2)(3) It also can lead to dilation of the aorta, predisposing individuals to a significantly higher risk of aortic aneurysm and dissection. (4) Although most individuals with BAV present with these long-term complications during adulthood, a considerable number of patients may also present during childhood and adolescence with early-onset disease; that may require interventions in up to 12% to 15% of the patients. (5)(6) Therefore, patients with BAV require lifelong follow-up and surveillance. BAV has multiple implications in terms of sports participation and family screening, making it an important subject for primary care providers. This article reviews the anatomy, genetics, presentation, diagnosis, …

Tricuspid valve in congenital heart disease: multimodality imaging and electrophysiological considerations.

The tricuspid valve (TV) has been neglected for many years. Only recently, new studies demonstrated the prognostic role of the tricuspid valve lesions. In addition to that, new interventional approaches offer the possibility to noninvasively treat tricuspid valve disease. In this review, our aim was to summarize the role of different imaging techniques in the assessment of tricuspid valve with particular regards to congenital heart diseases. Finally, we analyze the importance of the TV and its adjacent regions from an electrophysiological point of view, both in structurally normal hearts and in congenital heart diseases. The most relevant transthoracic echocardiography (TTE) views to visualize the TV are the "modified" parasternal long axis, the apical views and subcostal projections, such as right oblique or left oblique views. However, simultaneous visualization of the three leaflets is possible only with three-dimensional TTE or, sometimes, in parasternal short axis and subcostal short axis views in children. 3D echocardiography is promising in this field. Indeed, its unique projections, such as en-face views from the right ventricular and atrial perspectives, are able to define the spatial relationship of the tricuspid leaflets with the surrounding structures. Moreover, multimodality imaging assessment has been recently proposed for the diagnostic assessment of the TV, especially before percutaneous intervention. Cardiac computed tomography provides valuable anatomic spatial information of the TV apparatus. Cardiac magnetic resonance is able to provide, noninvasively, detailed morphological and functional information of the valve.

Methicillin-resistant Staphylococcus aureus-induced right-sided infective endocarditis detected by transthoracic echocardiography: the importance of parasternal short-axis view screening.

Methicillin-resistant Staphylococcus aureus-induced right-sided infective endocarditis detected by transthoracic echocardiography: the importance of parasternal short-axis view screening.