Neoaortic Regurgitation Detected by Echocardiography After Arterial Switch Operation: A Systematic Review and Meta-Analysis.

Background: Neoaortic root dilatation (NeoARD) and neoaortic regurgitation (NeoAR) are common sequelae following the arterial switch operation (ASO) for transposition of the great arteries. Objectives: The authors aimed to estimate the cumulative incidence of NeoAR, assess whether larger neoaortic root dimensions were associated with NeoAR, and evaluate factors associated with the development of NeoAR during long-term follow-up. Methods: Electronic databases were systematically searched for articles that assessed NeoAR and NeoARD after ASO, published before November 2022. The primary outcome was NeoAR, classified based on severity categories (trace, mild, moderate, and severe). Cumulative incidence was estimated from Kaplan-Meier curves, neoaortic root dimensions using Z-scores, and risk factors were evaluated using random-effects meta-analysis. Results: Thirty publications, comprising a total of 6,169 patients, were included in this review. Pooled estimated cumulative incidence of ≥mild NeoAR and ≥moderate NeoAR at 30-year follow-up were 67.5% and 21.4%, respectively. At last follow-up, neoaortic Z-scores were larger at the annulus (mean difference [MD]: 1.17, 95% CI: 0.52-1.82, P < 0.001; MD: 1.38, 95% CI: 0.46-2.30, P = 0.003) and root (MD: 1.83, 95% CI: 1.16-2.49, P < 0.001; MD: 1.84, 95% CI: 1.07-2.60, P < 0.001) in patients with ≥mild and ≥moderate NeoAR, respectively, compared to those without NeoAR. Risk factors for the development of any NeoAR included prior pulmonary artery banding, presence of a ventricular septal defect, aorto-pulmonary mismatch, a bicuspid pulmonary valve, and NeoAR at discharge. Conclusions: The risks of NeoARD and NeoAR increase over time following ASO surgery. Identified risk factors for NeoAR may alert the clinician that closer follow-up is needed. (Risk factors for neoaortic valve regurgitation after arterial switch operation: a meta-analysis; CRD42022373214).

Impact of Phlebotomy Volume Knowledge on Provider Laboratory Ordering and Transfusion Practices in the Pediatric Cardiac ICU.

OBJECTIVES: Phlebotomy can account for significant blood loss in post-surgical pediatric cardiac patients. We investigated the effectiveness of a phlebotomy volume display in the electronic medical record (EMR) to decrease laboratory sampling and blood transfusions. Cost analysis was performed. DESIGN: This is a prospective interrupted time series quality improvement study. Cross-sectional surveys were administered to medical personnel pre- and post-intervention. SETTING: The study was conducted in a 19-bed cardiac ICU (CICU) at a Children's hospital. PATIENTS: One hundred nine post-surgical pediatric cardiac patients weighing 10 kg or less with an ICU stay of 30 days or less were included. INTERVENTIONS: We implemented a phlebotomy volume display in the intake and output section of the EMR along with a calculated maximal phlebotomy volume display based on 3% of patient total blood volume as a reference. MEASUREMENTS AND MAIN RESULTS: Providers poorly estimated phlebotomy volume regardless of role, practice setting, or years in practice. Only 12% of providers reported the availability of laboratory sampling volume. After implementation of the phlebotomy display, there was a reduction in mean laboratories drawn per patient per day from 9.5 to 2.5 ( p = 0.005) and single electrolytes draw per patient over the CICU stay from 6.1 to 1.6 ( p = 0.016). After implementation of the reference display, mean phlebotomy volume per patient over the CICU stay decreased from 30.9 to 14.4 mL ( p = 0.038). Blood transfusion volume did not decrease. CICU length of stay, intubation time, number of reintubations, and infections rates did not increase. Nearly all CICU personnel supported the use of the display. The financial cost of laboratory studies per patient has a downward trend and decreased for hemoglobin studies and electrolytes per patient after the intervention. CONCLUSIONS: Providers may not readily have access to phlebotomy volume requirements for laboratories, and most estimate phlebotomy volumes inaccurately. A well-designed phlebotomy display in the EMR can reduce laboratory sampling and associated costs in the pediatric CICU without an increase in adverse patient outcomes.

Derivation and Validation of a General Predictive Model for Long Term Risks for Mortality and Invasive Interventions in Congenital and Acquired Cardiac Conditions Encountered in the Young.

Accurate prognostic assessment is a key driver of clinical decision making in heart disease in the young (HDY). This investigation aims to derive, validate, and calibrate multivariable predictive models for time to surgical or catheter-mediated intervention (INT) and for time to death in HDY. 4108 unique subjects were prospectively and consecutively enrolled, and randomized to derivation and validation cohorts. Total follow-up was 26,578 patient-years, with 102 deaths and 868 INTs. Accelerated failure time multivariable predictive models for the outcomes, based on primary and secondary diagnoses, pathophysiologic severity, age, sex, genetic comorbidities, and prior interventional history, were derived using piecewise exponential methodology. Model predictions were validated, calibrated, and evaluated for sensitivity to changes in the independent variables. Model validity was excellent for predicting mortality and INT at 4 months, 1, 5, 10, and 22 years (areas under receiver operating characteristic curves 0.813-0.915). Model calibration was better for INT than for mortality. Age, sex, and genetic comorbidities were significant independent factors, but predicted outcomes were most sensitive to variations in composite predictors incorporating primary diagnosis, pathophysiologic severity, secondary diagnosis, and prior intervention. Despite 22 years of data acquisition, no significant cohort effects were identified in which predicted mortality and intervention varied by study entry date. A piecewise exponential model predicting survival and freedom from INT is derived which demonstrates excellent validity, and performs well on a clinical sample of HDY outpatients. Objective model-based predictions could educate both patient and provider, and inform clinical decision making in HDY.

Intramyocardial cell-based therapy with Lomecel-B during bidirectional cavopulmonary anastomosis for hypoplastic left heart syndrome: the ELPIS phase I trial.

Aims: Hypoplastic left heart syndrome (HLHS) survival relies on surgical reconstruction of the right ventricle (RV) to provide systemic circulation. This substantially increases the RV load, wall stress, maladaptive remodelling, and dysfunction, which in turn increases the risk of death or transplantation. Methods and results: We conducted a phase 1 open-label multicentre trial to assess the safety and feasibility of Lomecel-B as an adjunct to second-stage HLHS surgical palliation. Lomecel-B, an investigational cell therapy consisting of allogeneic medicinal signalling cells (MSCs), was delivered via intramyocardial injections. The primary endpoint was safety, and measures of RV function for potential efficacy were obtained. Ten patients were treated. None experienced major adverse cardiac events. All were alive and transplant-free at 1-year post-treatment, and experienced growth comparable to healthy historical data. Cardiac magnetic resonance imaging (CMR) suggested improved tricuspid regurgitant fraction (TR RF) via qualitative rater assessment, and via significant quantitative improvements from baseline at 6 and 12 months post-treatment (P < 0.05). Global longitudinal strain (GLS) and RV ejection fraction (EF) showed no declines. To understand potential mechanisms of action, circulating exosomes from intramyocardially transplanted MSCs were examined. Computational modelling identified 54 MSC-specific exosome ribonucleic acids (RNAs) corresponding to changes in TR RF, including miR-215-3p, miR-374b-3p, and RNAs related to cell metabolism and MAPK signalling. Conclusion: Intramyocardially delivered Lomecel-B appears safe in HLHS patients and may favourably affect RV performance. Circulating exosomes of transplanted MSC-specific provide novel insight into bioactivity. Conduct of a controlled phase trial is warranted and is underway.Trial registration number NCT03525418.

Evaluation of Regional Myocardial Work Indices in Pediatric Essential and Renal or Renovascular Hypertension.

BACKGROUND: Myocardial work (MW) is an index of LV function based on pressure-strain loops and brachial cuff pressure measurement. MW has been proposed as more sensitive than conventional functional parameters, as it accounts for afterload and myocardial deformation. However, many studies have been limited to assessment of global MW indices, neglecting regional differences in cardiac associated with hypertension and consequent cardiac remodeling. We aimed to quantify regional MW in pediatric hypertension and compare the findings in renal or renovascular hypertension (RHTN) with essential hypertension (EHTN). METHODS: We retrospectively assessed conventional markers of LV function, and both global and regional MW indices in 78 patients (49 males, 15.4 ± 2.94 years) with EHTN and RHTN. RESULTS: Peak systolic strain (PSS) in the basal septal segment was significantly impaired in patients with RHTN compared to EHTN (-13.00% [-15.50%; -13.00%] vs. -15.00% [-17.50%; -13.50%], P = 0.034). Similarly, basal septal MW indices were significantly elevated in patients with EHTN compared to RHTN, including MW efficiency (MWE) (95.0% [93.0%; 98.0%] vs. 94.0% [89.0%; 95.0%], P = 0.004) and constructive work (CW) (1700 mm Hg% (409 mm Hg%) vs. 1520 mm Hg% (336 mm Hg%), P = 0.037). Wasted work (WW) was significantly elevated in the RHTN group (79.0 mm Hg% [28.5 mm Hg%; 104 mm Hg%] vs. 105 mm Hg% [62.0 mm Hg%; 164 mm Hg%], P = 0.010). CONCLUSION: Significant differences in basal septal PSS and MW indices were observed between EHTN and RHTN. These findings highlight the usefulness of regional MW indices in assessing disease and may help differentiate between etiologies of pediatric hypertension.

Deterioration in myocardial work indices precedes changes in global longitudinal strain following anthracycline chemotherapy.

BACKGROUND: Left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) have conventionally been used for surveillance of cardiac function after cancer therapy, but indices of myocardial work (MW) are potentially superior for this purpose because they take into account both myocardial deformation and loading conditions. OBJECTIVES: We aimed to investigate the usefulness of MW in the follow-up of children and young adults following anthracycline chemotherapy. METHODS: Conventional markers of LV function (LV fractional shortening [LVFS], LVEF, GLS) and MW indices (global work index [GWI], global constructive work [GCW], global wasted work [GWW], and global work efficiency [GWE]) were obtained from 2342 echocardiographic examinations in 598 patients (354 male, 12.2 [4.7-17.3] years at initiation of chemotherapy). RESULTS: GWI, GCW, GLS, LVFS, and LVEF all deteriorated significantly during and after anthracycline chemotherapy, while GWW decreased and GWE was preserved. On multivariable analysis, MW indices were correlated with conventional markers of LV function and with clinical information relating to underlying malignancy and chemotherapy. Cox regression analysis revealed that similar levels of deterioration in GWW, GWI, and GCW preceded those in GLS, LFS, and LVEF. CONCLUSIONS: Non-invasive MW indices correlate well with conventional markers of LV function. Indices of MW appear to provide an earlier and more sensitive marker of progression towards chemotherapy-related cardiac dysfunction. Future studies are warranted to validate whether the incorporation of non-invasive MW into the routine clinical surveillance in patients after chemotherapy would improve outcomes.

Fetal Echocardiographic Predictors of Postnatal Surgical Strategies in Critical Pulmonary Stenosis or Atresia with Intact Ventricular Septum: A Meta-Analysis.

BACKGROUND: Critical pulmonary stenosis or atresia with intact ventricular septum (PSAIVS) may be managed either by biventricular repair or univentricular palliation. This systematic review and meta-analysis aimed to synthesize the evidence for the role of fetal echocardiography in predicting the postnatal treatment pathway. METHODS: PubMed/MEDLINE, CINHAL, Cochrane Library, Academic Search Complete, Web of Science, and Trip Pro were searched for observational studies published before July 2021. Random-effects meta-analysis was performed to identify factors associated with biventricular repair. RESULTS: Eleven individual studies published between 2006 and 2021, including a total of 285 participants (159 biventricular repair; 126 univentricular palliation), met our eligibility criteria. The pooled estimated prevalence of biventricular repair among patients with PSAIVS was 55.6% (95% confidence interval 48.5-62.5%). Those who underwent biventricular repair had greater right to left ventricle and tricuspid to mitral valve dimension ratios, greater TV z score, and longer TV inflow duration/cardiac cycle length by fetal echocardiography. They were also more likely to have significant tricuspid regurgitation and less likely to have ventriculo-coronary connections (VCCs). CONCLUSIONS: Commonly obtained fetal echocardiographic measurements have strong associations with treatment pathway choice for patients with PSAIVS. Greater RV growth appears to favor biventricular repair, whereas patients with VCC almost invariably undergo univentricular palliation. Future studies should aim to establish how these fetal echocardiographic parameters might predict outcomes for the two treatment pathways.

Left ventricular myocardial work indices in pediatric hypertension: correlations with conventional echocardiographic assessment and subphenotyping.

Myocardial work (MW) is a novel parameter that incorporates non-invasive estimates of left ventricular (LV) systolic pressure into the interpretation of strain, thus overcoming the limitations of load dependency traditionally encountered with LV fractional shortening (LVFS), ejection fraction (LVEF), and global longitudinal strain (GLS). However, data on MW in the pediatric population with hypertension are lacking. Conventional markers of LV function and MW indices were obtained from 88 echocardiographic examinations in 76 children with hypertension (47 males, 15.5 ± 2.96 years). When compared with a previously published cohort of 52 healthy controls, global work index (GWI) and global constructive work (GCW) were both significantly elevated while LVEF and GLS were not impaired but rather mildly increased. On multivariable analysis, GWI was correlated with systolic blood pressure (slope = + 16, p < 0.001) and GLS (slope = -100, p < 0.001), while GCW was correlated with systolic blood pressure (slope = + 18, p < 0.001), GLS (slope = -101, p < 0.001), male sex (slope = -75, p = 0.016), and LV mass (slope = -0.93, p < 0.001). Global wasted work (GWW) was correlated with age at echo visit (slope = -4.5, p = 0.005) and GLS (slope = + 5.5, p < 0.001). The opposite occurred for global work efficiency (GWE; slope = + 0.20, p = 0.011, and slope = -0.48, p < 0.001, respectively). Principal component analysis and k-means clustering revealed 4 subphenotypes which differed in terms of etiology, afterload, and compensation stage of the disease.    Conclusion: Non-invasive MW shows a good correlation with conventional markers of LV function and may help refine the assessment of hypertensive heart disease in children. What is Known: • Myocardial work (MW) is a novel parameter that incorporates non-invasive estimates of left ventricular (LV) systolic pressure into the interpretation of strain, thereby accounting for both deformation and afterload. • Although the usefulness of MW in the assessment of myocardial function beyond conventional markers has been demonstrated in various clinical populations, data in the pediatric population with hypertension are currently lacking. What is New: • Compared to normal values in healthy children, global work index and global constructive work were increased in those with hypertension, while LV ejection fraction and global longitudinal strain were not impaired. • Machine learning identified 4 subphenotypes which differed in terms of etiology, afterload, and compensation stage of the disease.

UNOS listing status-related changes in mechanical circulatory support utilization and outcomes in adult congenital heart disease patients.

BACKGROUND: The aim of this study was to investigate the impact of the new United Network for Organ Sharing (UNOS) listing criteria on mechanical circulatory support (MCS) utilization and outcomes in adult congenital heart disease (ACHD) patients. METHODS: We identified all ACHD and non-ACHD heart transplant candidates in the Scientific Registry of Transplant Recipients database listed during the 590 days prior to (historical cohort) or following (recent cohort) the UNOS allocation revision on October 18, 2018. Patients were grouped based on whether they received central temporary MCS (tMCS), peripheral tMCS, durable MCS, or no MCS. RESULTS: A total of 535 ACHD (242 historical, 293 recent) and 12,188 non-ACHD (6,258 historical, 5,930 recent) patients were included in our study. For ACHD patients, we found no differences in the historical versus recent cohort in utilization of central tMCS (3.31% vs 3.07%, p = .88) or durable MCS (3.31% vs 3.41%, p = .95), whereas the rate of peripheral tMCS increased (2.07% historical vs 6.83% recent, p = .009). Across both cohorts, ACHD patients supported with peripheral tMCS had shorter time-to-transplant than non-supported patients (25.7 vs 121.7 days, p = .002). ACHD patients supported with central tMCS had greater rates of post-transplant mortality relative to other ACHD patients (40.0% vs 12.6%, p = .006), while those supported with durable or peripheral temporary MCS had no differences in waitlist or post-transplant mortality compared to non-supported ACHD patients. CONCLUSIONS: The 2018 UNOS allocation changes increased utilization of peripheral temporary MCS in ACHD patients, decreasing waitlist time without impact on post-transplant outcomes.

End-Diastolic Forward Flow and Restrictive Physiology in Repaired Tetralogy of Fallot: A Systematic Review and Meta-Analysis.

Background Pulmonary arterial end-diastolic forward flow (EDFF) following repaired tetralogy of Fallot has been thought to represent right ventricular (RV) restrictive physiology, but is not fully understood. This systematic review and meta-analysis sought to clarify its physiological and clinical correlates, and to define a framework for understanding EDFF and RV restrictive physiology. Methods and Results PubMed/MEDLINE, Embase, Scopus, and reference lists of relevant articles were searched for observational studies published before March 2021. Random-effects meta-analysis was performed to identify factors associated with EDFF. Forty-two individual studies published between 1995 and 2021, including a total of 2651 participants (1132 with EDFF; 1519 with no EDFF), met eligibility criteria. The pooled estimated prevalence of EDFF among patients with repaired tetralogy of Fallot was 46.5% (95% CI, 41.6%-51.3%). Among patients with EDFF, the use of a transannular patch was significantly more common, and their stay in the intensive care unit was longer. EDFF was associated with greater RV indexed volumes and mass, as well as smaller E-wave velocity at the tricuspid valve. Finally, pulmonary regurgitation fraction was greater in patients with EDFF, and moderate to severe pulmonary regurgitation was more common in this population. Conclusions EDFF is associated with dilated, hypertrophied RVs and longstanding pulmonary regurgitation. Although several studies have defined RV restrictive physiology as the presence of EDFF, our study found no clear indicators of poor RV compliance in patients with EDFF, suggesting that EDFF may have multiple causes and might not be the precise equivalent of RV restrictive physiology.

Oxygen Uptake Efficiency Slope Predicts Adverse Outcome Following Atrial Switch Procedure.

Prior to the 1990s, d-TGA was palliated with the atrial switch procedure resulting in a systemic right ventricle associated with significant long-term morbidity and mortality. Determining the optimal timing of heart transplantation (HT) in these patients has been difficult. While cardiopulmonary exercise testing (CPET) is commonly used to try and risk stratify these patients, traditional exercise parameters have lacked the sensitivity and specificity to assess long-term risk. We sought to assess changes in exercise parameters over time in order to determine if any CPET parameter or combination of parameters could reliably identify risk for adverse outcome in this patient group. A retrospective review of serial CPET for 40 patients over 17 years was completed. Patients with adverse event within 6 months prior to CPET were noted. CPET parameters were compared and linear mixed model regression with repeated measures was performed on serial tests for longitudinal assessment. The linear mixed model regression identified OUES indexed to BSA to be the most sensitive parameter in identifying patients at risk of adverse event and became a stronger predictor of adverse event when combined with peak heart rate. CPET is useful in identifying patients with atrial switch at increased risk of adverse outcome. Indexed OUES and peak heart rate are better prognostic indicators than VO2 and VE/VCO2.

Artificial intelligence in pediatric cardiology: taking baby steps in the big world of data.

PURPOSE OF REVIEW: Artificial intelligence (AI) has changed virtually every aspect of modern life, and medicine is no exception. Pediatric cardiology is both a perceptual and a cognitive subspecialty that involves complex decision-making, so AI is a particularly attractive tool for this medical discipline. This review summarizes the foundational work and incremental progress made as AI applications have emerged in pediatric cardiology since 2020. RECENT FINDINGS: AI-based algorithms can be useful for pediatric cardiology in many areas, including: (1) clinical examination and diagnosis, (2) image processing, (3) planning and management of cardiac interventions, (4) prognosis and risk stratification, (5) omics and precision medicine, and (6) fetal cardiology. Most AI initiatives showcased in medical journals seem to work well in silico, but progress toward implementation in actual clinical practice has been more limited. Several barriers to implementation are identified, some encountered throughout medicine generally, and others specific to pediatric cardiology. SUMMARY: Despite barriers to acceptance in clinical practice, AI is already establishing a durable role in pediatric cardiology. Its potential remains great, but to fully realize its benefits, substantial investment to develop and refine AI for pediatric cardiology applications will be necessary to overcome the challenges of implementation.

Donor Characteristics and Recipient Outcomes After Heart Transplantation in Adult Congenital Heart Disease.

Background Patients with adult congenital heart disease (ACHD) experience long waitlist times for heart transplantation (HTx) while a large proportion of donor hearts are refused. The goal of this study was to inform optimal donor selection for patients with ACHD listed for HTx by examining the impact of donor characteristics on post-HTx outcomes. Methods and Results Using the Scientific Registry of Transplant Recipients, we conducted a retrospective analysis of patients aged ≥18 years listed for HTx in the United States between 2000 and 2016. We compared waitlist times between patients with ACHD and patients with noncongenital heart disease and constructed multivariate hazard models to identify donor characteristics associated with increased waitlist time. We then compared post-HTx survival between patients with ACHD and patients with noncongenital heart disease and constructed multivariate hazard models to identify donor characteristics associated with mortality. There were very few differences in donor characteristics between HTx recipients with ACHD and those with noncongenital heart disease. Status 1A-listed patients with ACHD experienced longer waitlist times compared with patients with noncongenital heart disease. Increased wait times were associated with some donor characteristics. Post-HTx outcomes varied over time, with patients with ACHD having inferior early mortality (0 to 30 days), similar intermediate mortality (31 days to 4 years), and superior late mortality (>4 years). We identified no donor characteristics associated with mortality to justify the observed differences in donor selection or waitlist time. Conclusions HTx candidates with ACHD wait longer for transplant but do not require unique donor selection criteria. HTx teams should consider liberalizing donor criteria and focusing only on evidence-based selection to improve waitlist outcomes and reduce the recipient-donor disparity.

Assessment of mitral valve function in children and young adults with hypertrophic cardiomyopathy using three-dimensional echocardiography.

OBJECTIVE: The objective of this study was to assess papillary muscle (PM) and mitral valve (MV) structure and function in children and young adults with mild and moderate hypertrophic cardiomyopathy (HCM) using real-time three-dimensional echocardiography (3DE) and to correlate them with HCM related adverse outcomes. METHODS: Transthoracic research 3DE was performed in HCM patients and controls matched for age and gender. Anterolateral and posteromedial PM mass, apical displacement of anterolateral PM, and left ventricular (LV) mass were measured and indexed to body surface area. The MV annulus and leaflet structure and function were analyzed. Individual PMs were manually planimetered by tracing the endocardial borders on each mid systole frame, taking care to distinguish PMs as distinct from the LV wall. Apical PM displacement was expressed as ratio of the distance between the apex and the base of the anterolateral PM to the entire length of the LV lateral wall (APL index). All 3DE measurements were correlated to adverse outcomes. RESULTS: Forty subjects were studied, including 20 HCM patients (age 18.1 ± 9.6 years, 16 male and 4 female), and 20 controls (18.2 ± 9.6 years, 16 male and 4 female). The indexed LV mass in HCM was 74.8 ± 25.8 g/m2 compared to 50.8 ± 12.4 g/m2 in controls (p = 0.001). The anterolateral, posteromedial and combined PM mass were 3.1 ± 2.2 g/m2, 1.7 ± 1.2 g/m2 and 4.9 ± 2.7 g/m2 in HCM, in contrast to respective measurements of 1.1 ± 0.6 g/m2, 1.2 ± 0.6 g/m2 and 2.3 ± 0.8 g/m2 in controls (p < 0.001, p = 0.062, and p < 0.001, respectively). The mitral valve annular parameters (annulus circumference, height and area) in HCM were not significantly different from controls. The APL index in HCM was less than in controls (0.44 ± 0.07 vs. 0.55 ± 0.04, p < 0.001). The LV lateral wall length and LV mass correlated with adverse HCM outcomes, while the APL index and PM total mass were not associated with adverse events. CONCLUSION: It is feasible to evaluate PM muscles and MV annulus geometry in children and young adults with HCM using 3DE. The morphologic and functional changes of anterolateral PM may occur in the absence of MV annulus changes. Prospective validation will be required to determine if LV lateral wall length and LV mass may be used as predictors of adverse events.

Dynamic Systolic Changes in Tricuspid Regurgitation Vena Contracta Size and Proximal Isovelocity Surface Area in Hypoplastic Left Heart Syndrome: A Three-Dimensional Color Doppler Echocardiographic Study.

BACKGROUND: The aims of this study were to investigate the dynamic changes in the vena contracta (VC) and proximal isovelocity surface area (PISA) through systole in patients with hypoplastic left heart syndrome and tricuspid regurgitation and to identify the stage of systole (early, mid, or late) in which VC and PISA radius are optimal. METHODS: Twenty-eight patients with hypoplastic left heart syndrome were prospectively studied using continuous two-dimensional (2D) and three-dimensional (3D) echocardiography. Two-dimensional VC width, 3D VC area, and PISA radii (2D and 3D) were measured frame by frame throughout systole. The maximal 2D VC width, 3D VC area, and PISA radii in the first, middle, and last thirds of systole were compared, and correlations were explored with 3D tricuspid annular areas, right atrial volumes, and right ventricular volumes. RESULTS: In all, 35 data sets that met inclusion criteria were analyzed. On frame-by-frame analysis, maximal 2D VC width and 3D VC area were found in the first third of systole in 17% and 20% of studies, in the second third in 34% and 31%, and in the final third in 49% and 49%. Similarly, the maximal 2D and 3D PISA radii were found in the first third of systole in 26% and 17% of studies, in the second third in 28% and 34%, and in the final third in 46% and 49%. CONCLUSIONS: In hypoplastic left heart syndrome, detailed temporal analysis of tricuspid regurgitation-associated VC and PISA by 2D and 3D echocardiography reveals no reliable pattern predicting when in systole these parameters peak. Frame-by-frame measurement is necessary for identification of maximal VC and PISA radius on 2D and 3D color Doppler echocardiography because the severity of tricuspid regurgitation could be underestimated because of temporal variability in VC and PISA.

Characterization of left ventricular cavity flow, wall stress and energy loss by color doppler vector flow mapping in children and adolescents with cardiomyopathy.

BACKGROUND: Vector flow mapping is an emerging echocardiographic method allowing for investigation of intracardiac blood flow mechanics, wall shear stress (WSS), and energy loss (EL). We hypothesized that alterations in EL and WSS will differ among subjects with hypertrophic (HCM), dilated (DCM) cardiomyopathy, and normal controls. METHODS: Echocardiograms were prospectively performed with the ProSound F75CV (Hitachi HealthCare., Tokyo, Japan) on all subjects. 2D color Doppler cine loop images were obtained from apical 5 and the apical long axis views and stored digitally. Measurements were averaged over three cardiac cycles using VFM software to derive flow patterns, WSS, and EL. Standard left ventricular (LV) systolic and diastolic functional parameters were also obtained. RESULTS: A total of 85 subjects, 22 with HCM (age 18 ± 9 yrs.), 18 DCM (age 18 ± 9 yrs.), and 45 age and gender matched controls were included in the study. Diastolic wall shear stress was found significantly different in HCM (0.004 ± 0.185 N/m2) compared with DCM (0.397 ± 0.301 N/m2, P < 0.001), and controls (0.175 ± 0.255 N/m2, P = 0.027). Furthermore, indexed systolic EL was found to be significantly elevated in HCM (13.91 ± 13.17 mW/m2/m3) compared with DCM (8.17 ± 9.77 mW/m2/m3, P < 0.001), but not controls (6.45 ± 7.47 mW/m2/m3). CONCLUSION: Differences in abnormal ventricular mechanics observed in HCM and DCM are reflected in both EL and WSS, and are suggestive that changes in energetic parameters may represent novel indices of ventricular dysfunction.

The discerning ear: cardiac auscultation in the era of artificial intelligence and telemedicine.

Heart murmur, a thoracic auscultatory finding of cardiovascular origin, is extremely common in childhood and can appear at any age from premature newborn to late adolescence. The objective of this review is to provide a modern examination and update of cardiac murmur auscultation in this new era of artificial intelligence (AI) and telemedicine. First, we provide a comprehensive review of the causes and differential diagnosis, clinical features, evaluation, and long-term management of paediatric heart murmurs. Next, we provide a brief history of computer-assisted auscultation and murmur analysis, along with insight into the engineering design of the digital stethoscope. We conclude with a discussion of the paradigm shifting impact of deep learning on murmur analysis, AI-assisted auscultation, and the implications of these technologies on telemedicine in paediatric cardiology. It is our hope that this article provides an updated perspective on the impact of AI on cardiac auscultation for the modern paediatric cardiologist.

The QT Interval in Patients With the Turner Syndrome.

Patients with the Turner syndrome (TS) often have longer QT intervals compared with age-matched peers although the significance of this remains unknown. We sought to determine the degree, frequency and impact of QTc prolongation in patients with TS. A chart review of all patients with an electrocardiogram (ECG) and genetically proven TS was performed. Medications at the time of the ECG were reviewed and QTc calculated. Medications were classified according to QTc risk using www.crediblemeds.com. ECG parameters were compared with an age, gender, and cardiac lesion-matched control group. Over the 10-year period of review, 112 TS patients with a mean age of 34 ± 25 years underwent 226 ECGs. At least 1 QTc prolonging medication was prescribed in 81 (74%) patients. Longer QTc interval correlated with absence of y chromosomal material (p = 0.01), older age (p <0.0001), increased number of QTc prolonging and nonprolonging medications (p <0.0001 each). During the 7.0 ± 5.1 years of follow-up, no patient had ventricular arrhythmia or unexplained sudden death. QTc was significantly shorter in matched controls using either Bazett or Hodges formula (424 ± 16 ms vs 448 ± 28 ms, p <0.0001; and 414.8 ± 16 ms vs 424.2 ± 20 ms; p = 0.0002, respectively). However, there was no difference in the frequency of QTc prolongation >460 msec (2.8% vs 2.6%, p = 0.9). In conclusion, despite frequent use of QT-prolonging medications, ventricular arrhythmias are rare in TS.