The Use of Virtual Reality Echocardiography in Medical Education.

Virtual reality (VR) is a relatively new technology that allows an individual to experience a virtual world. This new immersive video type may be of particular usefulness in procedure-based healthcare settings. We hypothesized that VR echocardiography was non-inferior to live demonstration. Our aim was to assess the usefulness of a VR echocardiographic approach in teaching echocardiography to pediatric trainees compared to live demonstration. This was a single center, cross-sectional observational design. We used a Garmin VIRB® 360 and a head-mount display to record live echocardiography exams in a pediatric population. An Oculus Go™ was used to view the 360° immersive/VR videos. Trainees responded to a written questionnaire afterwards. Fifteen trainees participated in the study, each of whom had previously seen echocardiography through live demonstration teaching. Eleven respondents had previous hands-on echocardiography experience. All 15 participants confirmed that VR echocardiography is a useful teaching tool with 87% (n = 13) rating it as good or very good on a 5-point Likert scale. When asked to compare VR to live demonstration, 67% (n = 10) rated VR echocardiography as the same or better than live demonstration. One of the participants reported a side effect, namely mild and self-resolving dizziness. VR echocardiography is a safe, inexpensive and practical way for trainees to learn echocardiography. The addition of VR echocardiography to the arsenal of teaching tools may enrich the learning experience for trainees.

Inter-observer and Inter-vendor Variability in Strain Measurements in Patients with Single Right Ventricular Anatomy.

Myocardial strain offers new insights into ventricular performance, There are software packages from several different companies used to ascertain this, and little data is available in patients with single right ventricle (sRV) physiology. We aimed to compare the analysis of two strain software applications using a cohort of patients with sRV for both inter-vendor and inter-observer variability. Echocardiograms from 85 patients with sRV (122 separate studies) were prospectively evaluated. All had Glenn and/or Fontan palliation. Longitudinal 4-chamber (4LS), inflow/outflow (IO), circumferential, and radial strain were assessed using Velocity Vector Imaging (VVI, Seimens, Munich) and Automated Functional Imaging (AFI, General Electric, Boston) software. In a subset of 45 patients (61 separate studies), strain measurements were obtained by two sonographers so a paired "inter-observer" analysis could be performed. A moderate correlation between measurements made by the two systems was observed. Circumferential strain assessment had the highest R value (0.77) with all others having R values < 0.6. Both software packages showed modest inter-observer reproducibility for longitudinal and circumferential strain. VVI intraclass correlation coefficients (ICC) for 4LS and average circumferential strain (ACS) were 0.6 and 0.58, compared to 0.68 and 0.59 for AFI. Other than radial strain and VVI IO inferior strain, mean strain differences between AFI and VVI were ≤ 1%. Inter-observer variability is modest, however, mean differences are minimal suggesting reasonable clinical reliability. Inter-vendor variability is greater and not as clinically reliable. In patients with sRV, serial assessments with strain should be performed using the same software.

Application of the Pediatric Appropriate Use Criteria for Chest Pain.

OBJECTIVES: To characterize the subgroup of outpatient pediatric patients presenting with chest pain and to determine the effectiveness of published pediatric appropriate use criteria (PAUC) to detect pathology. STUDY DESIGN: The Pediatric Appropriate Use of Echocardiography study evaluated the use and yield of transthoracic echocardiography (TTE) before and after PAUC release. Data were reviewed on patients ?18 years of age who underwent TTE for chest pain. Indications were classified as appropriate (A), may be appropriate (M), and rarely appropriate (R) based on PAUC ratings, and findings were normal, incidental, or abnormal. RESULTS: Chest pain was the primary indication in 772 of 4562 outpatient TTE studies (17%) (median age 14 years, IQR 10-16) ordered during the study period: 458 of 772 before (59%) and 314 of 772 after (41 %) the release of PAUC with no change in appropriateness. In A indications (n?=?654), 642 (98%) were normal, 5 (1%) had incidental findings, and 7 (1%) were abnormal. A and M detected 100% of all abnormal findings (A: n?=?7; M: n?=?6; R: n?=?0), with an association between ratings and findings (P?<.001). There was no association between R rating and any pathology. CONCLUSIONS: There was no change in ordering patterns with publication of the PAUC. Despite the high rate of TTEs ordered for indications rated A, most studies were normal. Studies that detected pathology were performed for indications rated A or M, but not R. This study supports PAUC as a useful tool in pediatric chest pain evaluation that may subsequently improve the use of TTE.

Application of pediatric appropriate use criteria for initial outpatient evaluation of syncope.

BACKGROUND: Syncope is a common reason for outpatient transthoracic echocardiography (TTE). We studied the applicability of pediatric appropriate use criteria (AUC) on initial outpatient evaluation of children (≤18 years) with syncope. METHODS: Data were obtained before (Phase I, April-September 2014) and after (Phase II, January-April 2015) the release of the AUC document from six participating pediatric cardiology centers. Site investigators determined the indication for TTE and assigned appropriateness rating based on the AUC document: Appropriate (A), May Be Appropriate (M), Rarely Appropriate (R), or "unclassifiable" (U) if it did not fit any scenario in the AUC document. RESULTS: Of the total 4562 TTEs, 310 (6.8%) were performed for syncope: 174/2655 (6.6%) Phase I and 136/1907 (7.1%) Phase II, P=.44. Overall, 168 (50.5%) were for indications rated A, 63 (18.9%) for M, 79 (23.7%) for R, and 23 (6.9%) for U. Release of AUC did not change the appropriateness of TTEs [A=51.6% vs 49.0%, P=.63, R=20.2% vs 28.3%, P=.09]. Overall syncope-related R indications formed 15.7% of R indications for all the echocardiograms performed in the entire Pediatric Appropriate Use (PAUSE) study (11.9% Phase I and 22.4% Phase II, P=.002). TTEs were normal in majority of the patients except 7 that had incidental findings. CONCLUSIONS: In conclusion, syncope is a common reason for indications rated R and release of the AUC document did not improve appropriate utilization of TTE in syncope. Targeted educational interventions are needed to reduce unnecessary TTEs in children with syncope.

Electrocardiographic abnormalities in elite high school athletes: comparison to adolescent hypertrophic cardiomyopathy.

BACKGROUND: In athletes, ECG changes from physiological cardiac remodelling are common but can overlap with findings from a pathological disorder. We compared ECG findings in a group of elite high school athletes to a cohort of adolescents with hypertrophic cardiomyopathy (HCM). METHODS/RESULTS: We prospectively performed 15-lead ECGs and echocardiograms in 147 elite high school athletes. Student-athlete ECGs were compared in blinded fashion to ECGs of 148 adolescents with HCM of similar age and ethnicity. Standard ECG hypertrophy criteria and established expert opinion guidelines (European Society of Cardiology, ESC and Seattle criteria) were analysed. All student-athletes had normal echocardiograms. Overall, 77/147 (52%) of student-athletes met standard ECG criteria for ventricular hypertrophy compared to 126/148 (85%) adolescents with HCM (p<0.0001). There were 112/148 (76%) adolescents with HCM who had pathological Q-waves, T-wave inversion and/or ST-segment depression compared to 1/147 (1%) athletes (p<0.0001). Most patients with HCM (84%, 124/148) had ≥1 abnormal ECG finding(s) according to Seattle criteria, compared to 1% of student-athletes (2/147). Similarly, 130/148 (88%) patients with HCM met group-2 ESC criteria (abnormal), compared to 36/147 (24%) student-athletes (p<0.0001). CONCLUSIONS: Over 50% of elite high school athletes with echocardiographically confirmed normal hearts satisfied standard voltage criteria for ventricular hypertrophy. Pathological Q-waves, T-wave inversion or ST-segment depression were most helpful in distinguishing adolescents with HCM from normals. Both ESC and Seattle criteria successfully stratified the student-athlete and HCM cohorts, however each had a false-negative rate >10% for the HCM cohort. The Seattle criteria demonstrated a significantly lower false-positive rate (1%) than the ESC criteria (24%).

Two-dimensional measurement of tricuspid annular plane systolic excursion in children: can it substitute for an m-mode assessment?

BACKGROUND: Tricuspid annular plane systolic excursion measured by M-mode (MM-TAPSE) has been validated as a marker of right ventricular systolic performance. A similar measurement by 2D imaging (2D-TAPSE) can be obtained. We sought to determine the correlation and strength of agreement between MM-TAPSE and 2D-TAPSE in children. METHODS: Echocardiographic studies performed for clinical indications were reviewed retrospectively. All consecutive subjects ≤18 years of age were included. The cohort was divided into those with normal echocardiographic findings and those with disorders affecting the right ventricle. Digitally recorded images were analyzed for both MM-TAPSE and 2D-TAPSE. Measurements of 2D-TAPSE were made in an apical four-chamber view, from the tricuspid valve annulus to a consistent point at the apex of the imaging sector at end-diastole and end-systole, with the difference representing the 2D-TAPSE value. RESULTS: A total of 329 subjects (mean age 9.0 ± 6.1 years) met entry criteria. Correlation coefficient between MM-TAPSE and 2D-TAPSE was 0.90. Bland-Altman analysis showed agreement between the two methods to be within 1.2 ± 2.6 mm (mean percentage difference of 6.5%). About 1 mm difference between MM-TAPSE and 2D-TAPSE was consistently observed in all diagnostic subgroups, and across all age categories. CONCLUSION: MM-TAPSE and 2D-TAPSE correlate strongly, with 2D-TAPSE being consistently about 1 mm less than values obtained by the M-mode technique. We conclude that 2D-TAPSE can provide a reliable alternative to MM-TAPSE to quantitatively measure right ventricular systolic function and may be especially useful in situations where retrospective comparisons are sought.

Pediatric sex estimation using AI-enabled ECG analysis: influence of pubertal development.

AI-enabled ECGs have previously been shown to accurately predict patient sex in adults and correlate with sex hormone levels. We aimed to test the ability of AI-enabled ECGs to predict sex in the pediatric population and study the influence of pubertal development. AI-enabled ECG models were created using a convolutional neural network trained on pediatric 10-second, 12-lead ECGs. The first model was trained de novo using pediatric data. The second model used transfer learning from a previously validated adult data-derived algorithm. We analyzed the first ECG from 90,133 unique pediatric patients (aged ≤18 years) recorded between 1987-2022, and divided the cohort into training, validation, and testing datasets. Subgroup analysis was performed on prepubertal (0-7 years), peripubertal (8-14 years), and postpubertal (15-18 years) patients. The cohort was 46.7% male, with 21,678 prepubertal, 26,740 peripubertal, and 41,715 postpubertal children. The de novo pediatric model demonstrated 81% accuracy and an area under the curve (AUC) of 0.91. Model sensitivity was 0.79, specificity was 0.83, positive predicted value was 0.84, and the negative predicted value was 0.78, for the entire test cohort. The model's discriminatory ability was highest in postpubertal (AUC = 0.98), lower in the peripubertal age group (AUC = 0.91), and poor in the prepubertal age group (AUC = 0.67). There was no significant performance difference observed between the transfer learning and de novo models. AI-enabled interpretation of ECG can estimate sex in peripubertal and postpubertal children with high accuracy.

Effect of percutaneous atrial septal defect and patent foramen ovale device closure on degree of aortic regurgitation.

BACKGROUND: In recent years, percutaneous device closure has become commonplace for treatment of atrial septal defect (ASD) and patent foramen ovale (PFO). However, the effect of device closure on aortic valve regurgitation (AR) has been questioned. OBJECTIVE: The purpose of this study was to define changes in AR using echocardiography, before and after device closure of ASD or PFO. METHODS: We retrospectively reviewed all patients who had percutaneous device closure of ASD or PFO at our institution between 2005 and 2009. We compared the preprocedure echocardiogram to the most recent follow-up study. All investigators were blinded to referral diagnosis, patient demographics, and size and type of the device placed. Aortic regurgitation was graded as none/trivial, mild, moderate, or severe. RESULTS: Overall, 322 patients qualified for inclusion; 204 with PFO and 118 with ASD. Mean age at time of closure was 48 ± 20 years (range 3-85 years). Mean duration of follow-up was 1.2 years (range 2 months to 5 years). Only two patients (0.6%) demonstrated any appreciable increase in AR severity. However, both of these patients manifested a clinically insignificant change from a trivial to mild grade of aortic regurgitation. CONCLUSIONS: Percutaneous device closure of PFO or ASD does not increase the incidence or severity of AR over medium-term follow-up.

Unnatural history of the right ventricle in patients with congenitally malformed hearts.

The long-term outcome of patients with congenitally malformed hearts involving abnormal right ventricular morphology and haemodynamics is variable. In most instances, the patients are at risk for right ventricular failure, in part due to morphological differences between the right and left ventricles and their response to chronic volume and pressure overload. In patients after repair of tetralogy of Fallot, and after balloon valvotomy for valvar pulmonary stenosis, pulmonary regurgitation is the most significant risk factor for right ventricular dysfunction. In patients with a dominant right ventricle after Fontan palliation, and in those with systemic right ventricles in association with surgically or congenitally corrected transposition, the right ventricle is not morphologically capable of dealing with chronic exposure to the high afterload of the systemic circulation. In patients with Ebstein's malformation of the tricuspid valve, the degree of atrialisation of the right ventricle determines how well the right ventricle will function as the pump for the pulmonary vascular bed.

Echocardiography-Guided Risk Stratification for Long QT Syndrome.

BACKGROUND: The ability to identify those patients at the highest phenotypic risk for long QT syndrome (LQTS)-associated life-threatening cardiac events remains suboptimal. OBJECTIVES: This study sought to validate the association between electromechanical window (EMW) negativity, as derived from echocardiography, and symptomatic versus asymptomatic status in patients with LQTS. METHODS: We analyzed a cohort of 651 patients with LQTS (age 26 ± 17 years; 60% females; 158 symptomatic; 51% LQTS type 1; 33% LQTS type 2; 11% LQTS type 3; 5% multiple mutations) and 50 healthy controls. EMW was calculated as the difference between the interval from QRS onset to aortic valve closure midline, as derived for continuous-wave Doppler, and the electrocardiogram-derived QT interval for the same beat. RESULTS: A negative EMW was found among nearly all patients with LQTS compared to controls, with more profound EMW negativity in patients with symptomatic LQTS compared to those with asymptomatic LQTS (-52 ± 38 ms vs. -18 ± 29 ms; p < 0.0001). Logistic regression identified EMW, heart rate-corrected QT interval (QTc), female sex, and LQTS genotype as univariate predictors of symptomatic status. After multivariate analysis, EMW remained an independent predictor of symptomatic status (odds ratio for each 10-ms decrease in EMW: 1.37; 95% confidence interval: 1.27 to 1.48; p < 0.0001). EMW outperformed QTc in predicting symptomatic patients (area under the curve: 0.78 vs. 0.70; p = 0.01). After training and implementation, EMW correlation from echocardiographic sonographers showed excellent reliability (intraclass correlation coefficient: 0.93; 95% confidence interval: 0.89 to 0.96). CONCLUSIONS: In this validation study, patients with a history of LQTS-associated life-threatening cardiac events had a more profoundly negative EMW. EMW outperformed heart rate-corrected QT interval as a predictor of symptomatic status. EMW is now a clinically validated risk factor. In December 2019, our institution's echocardiography clinical practice committee approved use of EMW for patients with LQTS, making it a routinely reported echocardiographic finding.

Left ventricular diastolic dysfunction in HIV-uninfected infants exposed in utero to antiretroviral therapy.

OBJECTIVES: To longitudinally measure LV diastolic function in HIV-exposed but uninfected (HEU) children perinatally exposed to ART. DESIGN: HEU children who were perinatally exposed to antiretroviral therapy (ART) may be at risk for adverse cardiac effects. We have previously reported that those children have decreased left ventricular (LV) mass, dimension, and septal thickness with increased contractility. METHODS: Serial echocardiograms were obtained at specific times from birth to 48 months from two groups of HIV-uninfected children: 148 HIV-negative children who were perinatally exposed to ART and 130 non-ART-exposed HIV-unexposed healthy controls. The following LV diastolic indices were obtained: mitral valve early and late diastolic velocity (E and A), tissue Doppler-derived LV-free wall and septal early diastolic velocity (LV e' and sep e'). RESULTS: All echocardiographic indices were significantly different in ART-exposed children compared with ART-unexposed healthy controls. Both E and A were overall lower at all ages by 8.28 cm/s (P = 0.0002) and 13.46 cm/s (P < 0.0001) respectively. E/A ratio was higher by 0.27, 0.46, and 0.28 units at birth, 1 year and 2 years of age, respectively (all P ≤ 0.01). Moreover, LV e' and sep e' were overall lower at all ages by 0.84 cm/s (P = 0.01) and 0.47 cm/s (P = 0.02), respectively. CONCLUSION: Children who were exposed to ART in utero have subclinical yet significant differences in specific LV diastolic indices. Follow-up with serial echocardiograms are recommended in this population to further assess the potential cardiac toxicity of perinatal exposure to ART.

Noninvasive evaluation of left ventricular noncompaction: what's new in 2009?

Significant interest in clinical practice as well as the medical literature exists regarding the presentation and outcome of children and adults with left-ventricular noncompaction (LVNC). The mainstay in the diagnosis of LVNC has been the anatomic definition of the ventricular myocardium by two-dimensional echocardiographic imaging. Although helpful, this approach lacks diagnostic precision and fails to evaluate the functional impact of this abnormal myocardial architecture on global and regional myocardial performance. This review will focus on the use of novel echocardiographic modalities of tissue Doppler, strain, and strain rate imaging to identify and characterize abnormalities of regional myocardial function in patients with LVNC.

Myocardial deformation abnormalities in pediatric hypertrophic cardiomyopathy: are all etiologies identical?

AIMS: Hypertrophic cardiomyopathy (HCM) is a disease with a heterogeneous clinical and morphological presentation. It can be secondary to mutations in genes encoding for sarcomeric and non-sarcomeric proteins. The pattern of ventricular hypertrophy can vary from isolated basal septal to concentric hypertrophy. We investigated if there are differences in regional myocardial function in different forms of HCM. METHODS AND RESULTS: We performed echocardiograms on children with (i) isolated asymmetric septal HCM, (ii) isolated concentric HCM, (iii) Friedreich's ataxia associated with concentric HCM, and (iv) healthy controls. Wall thickness, left ventricular dimensions, ejection fraction, and mitral inflow were measured. Peak early diastolic myocardial velocities, peak systolic myocardial velocities, peak systolic strain rate (SR), peak systolic strain (epsilon), post-systolic shortening and time to maximal epsilon were measured in the basal and mid-septum and basal lateral wall to evaluate longitudinal myocardial function. Similar data were acquired and analysed in the anterior septum and infero-lateral wall to evaluate the radial myocardial function. All three groups with HCM had had increased wall thickness, reduced left ventricular dimensions, and evidence of impaired diastolic filling compared to controls. All forms of HCM had reduced early diastolic and systolic myocardial velocities and peak systolic SR and peak systolic epsilon compared with controls in all myocardial segments investigated. Children with asymmetric septal HCM had reduced systolic deformation, increased post-systolic shortening, and prolonged time to maximal epsilon in the basal septum compared with the other two groups with HCM. There were no differences in any echocardiographic variable between patients with isolated concentric HCM and Friedreich's ataxia and resulting HCM. CONCLUSION: Myocardial deformation is abnormal in all forms of paediatric HCM. Myocardial deformation is more reduced and associated with post-systolic shortening in the more hypertrophied basal septum in patients with asymmetric septal HCM. In contrast, this reduction is uniformly distributed in all myocardial segments in patients with concentric HCM irrespective of whether HCM results from isolated or secondary HCM. Our findings suggest the pattern of hypertrophy influences myocardial deformation more than the underlying cause of HCM.