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.

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.

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.

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.

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.

Progression of left ventricular diastolic function in the neonate and early childhood from transmitral color M-mode filling analysis.

BACKGROUND: We implemented sophisticated color M-mode analysis to assess age-dependent progression of left ventricular (LV) diastolic function. METHODS: Normal infants were prospectively enrolled for serial echocardiograms at 1 week, 1 month, 6 months, 1 year, and 2 years. From color M-mode scans, propagation velocity (VP), strength of filling (VS), and intraventricular pressure difference (IVPD) in 3 segments along apex-to-mitral valve scan line were measured. RESULTS: Age-wise comparisons of diastolic filling from 121 echocardiograms in 31 infants showed VP (cm/s), VS (cm2/s), and E-wave IVPD (mmHg) at 1 week to be 66.2 ± 11.9, 75.3 ± 19.9, and 1.5 ± 0.4, respectively, while VP, VS, and E-wave IVPD at 1 month were 80.3 ± 14.4, 101.2 ± 28.3, and 2.42 ± 1.1, respectively. There were significant differences in VP and segmental IVPD between first week and first month (p < 0.005) and IVPD between the age groups (p < 0.001). CONCLUSIONS: Comprehensive analysis of transmitral color M-mode data is feasible in infants, enabling calculation of pressure drop between the LV base and apex and strength of propagation from two distinct slopes. Profound changes very early followed by relatively constant filling mechanics in later infancy indicate significant LV maturation occurring during the first month of life. IMPACT: We implemented sophisticated analytic methods for color M-mode echocardiography in infants to assess age- and dimension-dependent changes in left ventricular diastolic function. Comprehensive characterization of transmitral color M-mode flow was feasible, enabling calculation of pressure drop between left ventricular base and apex and strength of propagation. Left ventricular diastolic filling function has predictable maturational progression, with significant differences in the intraventricular pressure between infants from birth to 2 years. This study forms the basis for future studies to examine alteration of early diastolic filling in congenital heart disease.

Can Abbreviated Cardiac Magnetic Resonance Imaging Adequately Support Clinical Decision Making After Repair of Tetralogy of Fallot?

Quantification of pulmonary regurgitation (PR), pulmonary flow distribution, and ventricular function is important for clinical surveillance in repaired Tetralogy of Fallot (TOF). Cardiovascular magnetic resonance (CMR) is the established reference, but cost, test duration, and patient discomfort are potential limitations to its serial use. We investigated whether an Abbreviated CMR protocol would alter clinical decisions in TOF from those that would have been made using a full protocol. Patients > 7 years with repaired TOF were identified. CMR was performed according to standard complete imaging protocol. CMRs were prepared in two ways, Full and Abbreviated and submitted for review by two imaging specialists. In conjunction with clinical information and case-specific quantitative CMR data (PR fraction, ventricular volumes, ejection fraction, branch pulmonary artery flow), Full and Abbreviated image sets were anonymized and uploaded for review. For the first half, Imager 1 received Abbreviated, and Imager 2 Full and for the remaining, Imager 1 received Full and Imager 2 received Abbreviated. Blinded to the other's choices, Imagers provided clinical decisions. Inter-rater agreement for each decision was measured. In all, 124 studies from 80 patients (mean 17.8 years) were analyzed. For 'intervention versus no-intervention' decision, the inter-rater agreement was strong [κ 0.75, p < 0.0001, 95% CI (0.630, 0.869)]. Agreement for recommended timing of follow-up imaging was good (κ 0.64, p < 0.0001, 95% CI (0.474, 0.811)] in the 'no-intervention' group. When raters were asked whether or not further imaging was necessary, agreement was modest [κ 0.363 (p < 0.0001), 95% CI (0.038, 0.687)]. In conclusion, Abbreviated CMR yield decisions for clinical care similar to those made using the standard full protocol. These results suggest a potential enhancement of clinical practice in which efficiency and cost saving might be achieved using Abbreviated CMR for routine follow-up surveillance of TOF.

Utility of expert focused cardiac ultrasound in paediatric cardiology outreach clinics.

OBJECTIVE: This prospective observational study evaluates the utility of expert focused cardiac ultrasound (eFCU) with spectral Doppler to inform decision making in established patients with specific, selected congenital cardiac defects in outreach clinics. Secondary objectives include determining if the addition of eFCU expands capacity in paediatric cardiology outreach clinics and if it improves the patient experience. METHODS: Patients aged 2 months to 19 years old with a diagnosis of ventricular septal defect, atrial septal defect, atrioventricular septal defect, patent ductus arteriosus, aortic valve stenosis, or pulmonary valve stenosis with the need for follow-up echocardiography in an outreach clinic from August 2017 to June 2018 were studied. A novel assessment tool was used to determine the success of eFCU. RESULTS: Forty-two patients from 11 clinics underwent eFCU with one unsuccessful exam making the failure rate 2.3% (95% CI 0.0006-0.1256). Addition of eFCU led to a significant increase in volume of patients able to be seen 19 versus 15.5 (p < 0.01). A majority of parents/patients reported a positive experience with eFCU. CONCLUSION: Expert focused cardiac ultrasound with spectral Doppler can be used successfully for follow-up in patients with select CHD and the addition of eFCU permits increased patient capacity in outreach clinics and has the potential to improve the patient experience.

Myocardial deformation assessed by longitudinal strain: Chamber specific normative data for CMR-feature tracking from the German competence network for congenital heart defects.

PURPOSE: Left ventricular two-dimensional global longitudinal strain (LS) is superior to ejection fraction (EF) as predictor of outcome. We provide reference data for atrial and ventricular global LS during childhood and adolescence by CMR feature tracking (FT). METHODS: We prospectively enrolled 115 healthy subjects (56 male, mean age 12.4 ± 4.1 years) at a single institution. CMR consisted of standard two-dimensional steady-state free-precession acquisitions. CMR-FT was performed on ventricular horizontal long-axis images for derivation of right and left atrial (RA, LA) and right and left ventricular (RV, LV) peak global LS. End-diastolic volumes (EDVs) and EF were measured. Correlations were explored for LS with age, EDV and EF of each chamber. RESULTS: Mean±SD of LS (%) for RA, RV, LA and LV were 26.56±10.2, -17.96±5.4, 26.45±10.6 and -17.47±5, respectively. There was a positive correlation of LS in LA, LV, RA and RV with corresponding EF (all P<0.05); correlations with age were weak. Gender-wise differences were not significant for atrial and ventricular LS, strain rate and displacement. Inter- and intra-observer comparisons showed moderate agreements. CONCLUSIONS: Chamber-specific nomograms for paediatric atrial and ventricular LS are provided to serve as clinical reference, and to facilitate CMR-based deformation research. KEY POINTS: • No normative data exist for CMR-derived global longitudinal strain in the young. • This prospective study provides reference data for atrial and ventricular longitudinal strain. • The data will serve as reference for CMR-based clinical and research use.

Assessment of ventriculo-vascular properties in repaired coarctation using cardiac magnetic resonance-derived aortic, left atrial and left ventricular strain.

OBJECTIVES: In patients with repaired coarctation of aorta (CoA), we assessed ventriculo-vascular characteristics using CMR-derived aortic area strain (AAS), left atrial (LA) and left ventricular (LV) longitudinal and circumferential strain (LS, CS). METHODS: Seventy-five subjects including 50 with repaired CoA divided into hypertensive (n = 25), normotensive (n = 25) and 25 controls were studied. AAS was measured at 3 levels: ascending aorta, proximal descending and descending aorta. LA and LV LS were measured using CMR-feature tracking. LA and LV end-diastolic volumes, ejection fraction (EF) and mass were measured. RESULTS: Mean patient age was 19.7 ± 6.7 and controls 23 ± 15 (years). All strains (LA, LV, ascending and descending aortic) were lower in CoA subgroups compared to controls except the AAS at diaphragm, which was not different. Comparisons between hypertensive and normotensive CoA showed no differences in LV mass, LV volumetric indices, and LA and LV strain indices; however, ascending AAS was lower in hypertensive subgroup (p = 0.02). Ascending AAS was correlated with LV mass (r = -0.4, p = 0.005), LVEF (r = -0.4, p = 0.004), systolic blood pressure (r = -0.5, p = 0.0001) and LVLS (r = 0.5, p = 0.001). CONCLUSIONS: Ascending AAS correlated with LV mass, EF and LVLS. In hypertensive CoA, ascending AAS was reduced compared to normotensive CoA and controls, indicating vascular remodelling differences influenced by ongoing hypertension. KEY POINTS: • Impaired arterial strain is a measure of increased stiffness in arteries • Ascending aorta strain correlates with left ventricular mass and longitudinal strain • Ascending aorta strain is significantly lower in hypertensive coarctation patients • Hypertension may be a consequence of vascular pathology persisting despite repair.

Traditional Long-Term Central Venous Catheters Versus Transhepatic Venous Catheters in Infants and Young Children.

OBJECTIVES: Children with congenital heart disease may require long-term central venous access for intensive care management; however, central venous access must also be preserved for future surgical and catheterization procedures. Transhepatic venous catheters may be an useful alternative. The objective of this study was to compare transhepatic venous catheters with traditional central venous catheters regarding complication rate and duration of catheter service. DESIGN: Retrospective review of 12 congenital heart disease patients from September 2013 to July 2015 who underwent placement of one or more transhepatic venous catheters. SETTING: Single freestanding pediatric hospital located in the central United States. PATIENTS: Pediatric patients with congenital heart disease who underwent placement of transhepatic venous catheter. INTERVENTIONS: Cohort's central venous catheter complication rates and duration of catheter service were compared with transhepatic venous catheter data. MEASUREMENTS AND MAIN RESULTS: Twelve patients had a total of 19 transhepatic venous lines. Transhepatic venous lines had a significantly longer duration of service than central venous lines (p = 0.001). No difference between the two groups was found in the number of documented thrombi, thrombolytic burden, or catheter sites requiring wound care consultation. A higher frequency of infection in transhepatic venous lines versus central venous lines was found, isolated to four transhepatic venous lines that had a total of nine infections. All but one was successfully managed without catheter removal. The difference in the proportion of infections to catheters in transhepatic venous lines versus central venous lines was significant (p = 0.0001), but no difference in the rate of infection-related catheter removal was found. CONCLUSIONS: Without compromising future central venous access sites, transhepatic venous lines had superior duration of service without increased thrombosis, thrombolytic use, or insertion site complications relative to central venous lines. Transhepatic venous catheters had a higher infection rate, and further investigation into the etiology is warranted.

Clinical Implications of a Multivariate Stratification Model for the Estimation of Prognosis in Ventricular Septal Defect.

OBJECTIVES: To derive and validate a multivariate stratification model for prediction of survival free from intervention (SFFI) in ventricular septal defect (VSD). A secondary aim is for this model to serve as proof of concept for derivation of a more general congenital heart disease prognostic model, of which the VSD model will be the first component. STUDY DESIGN: For 12 years, 2334 subjects with congenital heart disease were prospectively and consecutively enrolled. Of these, 675 had VSD and form the derivation cohort. One hundred seven other subjects with VSD followed in another practice formed the validation cohort. The derivation cohort was serially stratified based on clinical and demographic features correlating with SFFI. RESULTS: Six strata were defined, the most favorable predicting nearly 100% SFFI at 10 years, and the least favorable, a high likelihood of event within weeks. Strata with best SFFI had many subjects with nearly normal physiology, muscular VSD location, or prior intervention. In the validation cohort, the relation between predicted and actual SFFI at 6 months, 1 year, 2 years, and 5 years follow-up had areas under the receiver operating characteristic curves 0.800 or greater. CONCLUSIONS: A prediction model for SFFI in VSD has been derived and validated. It has potential for clinical application to the benefit of patients and families, medical trainees, and practicing physicians.

Increased hepatic stiffness as consequence of high hepatic afterload in the Fontan circulation: a vascular Doppler and elastography study.

UNLABELLED: Hepatic dysfunction is a recognized complication after Fontan palliation of congenital heart disease. We sought to quantitatively measure hepatic stiffness and vascular Doppler indices using ultrasound (US) and shear wave elastography (SWE) in a Fontan cohort. Subjects were prospectively recruited for echocardiography and real-time hepatic duplex US with SWE for hepatic stiffness (kPa). Doppler peak velocities, velocity time integral, resistive, pulsatility, acceleration indices (RI, PI, AI), and flow volume were measured in celiac artery, superior mesenteric artery, and main portal vein (MPV). A subset underwent cardiac catheterizations with liver biopsy. Correlations were explored between SWE, duplex, hemodynamic, and histopathologic data. In all, 106 subjects were studied including 41 patients with Fontan physiology (age 13.8 ± 6 years, weight 45.4 ± 23 kg) and 65 controls (age 15.0 ± 8.4 years, weight 47.9 ± 22 kg). Patients with Fontan physiology had significantly higher hepatic stiffness (15.6 versus 5.5 kPa, P < 0.0001), higher celiac RI (0.78 versus 0.73, P = 0.04) superior mesenteric artery RI (0.89 versus 0.84, P = 0.005), and celiac PI (1.87 versus 1.6, P = 0.034); while MPV flow volume (287 versus 420 mL/min in controls, P = 0.007) and SMA AI (829 versus 1100, P = 0.002) were lower. Significant correlation was seen for stiffness with ventricular end-diastolic pressure (P = 0.001) and pulmonary artery wedge pressure (P = 0.009). Greater stiffness correlated with greater degrees of histopathologic fibrosis. No significant change was seen in stiffness or other duplex indices with age, gender, time since Fontan, or ventricular morphology. CONCLUSION: Elevated hepatic afterload in Fontan, manifested by high ventricular end-diastolic pressures and pulmonary arterial wedge pressures, is associated with remarkably increased hepatic stiffness, abnormal vascular flow patterns, and fibrotic histologic changes. The MPV is dilated and carries decreased flow volume, while the celiac and superior mesenteric arterial RI is increased. SWE is feasible in this population and shows promise as a means for predicting disease severity on liver biopsy.

Fetal and neonatal imaging and strategy of primary neonatal heart transplantation in hypoplastic left heart with Ebstein's anomaly.

We present the anatomic constellation of mitral stenosis/aortic atresia variant of hypoplastic left heart syndrome, Ebstein's anomaly, and partial anomalous pulmonary venous return, an exceeding rare congenital heart defect. Prenatal echocardiography led to concern about the capacity of the right ventricle to increase cardiac output with lung expansion and pulmonary arterial runoff at birth, prompting the precaution of extracorporeal membrane oxygenator standby at delivery. Stage I palliation was not attempted, and control of pulmonary arterial blood flow was achieved with pulmonary artery banding, allowing sufficient ongoing hemodynamic stability. Orthotopic cardiac transplantation, repair of hypoplastic aortic arch, and primary sutureless repair of left pulmonary veins was performed, using dual-site arterial cannulation and continuous mild hypothermic cardiopulmonary bypass. We discuss how this unique echocardiographic anatomy influenced the surgical decision and point out how it guided therapy toward a strategy of primary transplantation rather than standard staged surgical palliation.

Transthoracic echocardiography in pediatric intensive care: impact on medical and surgical management.

OBJECTIVES: Although transthoracic echocardiography is commonly performed in the PICU, its utility is not specifically known. The purpose of this investigation was to evaluate the clinical impact of echocardiography in the PICU in terms of frequency of unanticipated findings and the frequency and nature of clinical management changes attributed to the results of echocardiography. DESIGN: Prospective cohort study. SETTING: Nineteen-bed combined medical-surgical-cardiac PICU at a tertiary care children's hospital. PATIENTS: All patients in PICU undergoing transthoracic echocardiography. INTERVENTIONS, MEASUREMENTS, AND MAIN RESULTS: Data collected included echocardiography indications, pre-echocardiography clinical assessment of anticipated echocardiography findings, height, weight, primary diagnosis, age, and urgency (stat vs routine) of echocardiography. Input of the attending care team (intensivist, cardiologist, and/or cardiovascular surgeon) allowed classification of echocardiography results as either confirming the pre-echocardiography impression, altering the pre-echocardiography clinical impression regarding the indication for which the test was performed, or altering the impression by virtue of new findings unrelated to the specific indication. The nature of the new findings were recorded and categorized. The team recorded clinical management changes made in response to the echocardiography results; the nature of these were listed and categorized. Echocardiograms (n = 416) were performed in 132 patients. Of these, 244 echocardiograms (59%) were ordered on male patients, 31% were under 30 days old, median age was 103 days, 379 (91%) had a primary cardiac diagnosis, and 92 (22%) were ordered stat. Sixty-three percent of echocardiograms confirmed and 24% altered the pre-echocardiography impression regarding the indication for the echocardiography; 13% introduced new findings unrelated to the indication. Cardiac surgical revision was the management change required in 26 patients (6.3%). Stat echocardiography was more likely to alter the pre-echocardiography assessment than routine echocardiography (p < 0.001). Management changes were more commonly associated with stat echocardiograms (p = 0.002) and those with new unexpected findings (p < 0.001) but had no demonstrable association with age less than 30 days (p = 0.332). CONCLUSIONS: Unanticipated echocardiography results are common in the PICU, and they often alter the clinical impressions that prompted the echocardiogram or introduce new findings unrelated to the reason for which the echocardiogram was recorded. Clinical management changes attributable to echocardiography findings are frequent in the PICU, including occasional surgical intervention. Echocardiography adds diagnostic value and contributes to the management approach in the PICU, accounting for its frequent use.

Subspecialty surveillance of long-term course of small and moderate muscular ventricular septal defect: heterogenous practices, low yield.

BACKGROUND: No expert consensus guides practice for intensity of ongoing pediatric cardiology surveillance of hemodynamically insignificant small and moderate muscular ventricular septal defect (mVSD). Therefore, despite the well-established benign natural history of mVSD, there is potential for widely divergent follow up practices. The purpose of this investigation was to evaluate (1) variations in follow up of mVSD within an academic children's hospital based pediatric cardiology practice, and (2) the frequency of active medical or surgical management resulting from follow up of mVSD. METHODS: We retrospectively reviewed records of 600 patients with isolated mVSD echocardiographically diagnosed between 2006 and 2012. Large mVSD were excluded (n = 4). Patient age, gender, echocardiographic findings, provider, recommendations for follow up, and medical and surgical management were tabulated at initial and follow up visits. Independent associations with follow up recommendations were sought using multivariate analysis. RESULTS: Initial echocardiography showed small single mVSD in 509 (85%), multiple small mVSD in 60 (10%), and small-to-moderate or moderate single mVSD in 31 (5%). The mean age at diagnosis was 15.9 months (0-18.5 years) and 25.7 months (0-18.5 years) at last follow up. There was slight female predominance (56.3%). Fourteen pediatric cardiology providers recommended 316 follow up visits, 259 of which were actually accomplished. There were 37 other unplanned follow up visits. No medical or surgical management changes were associated with any of the follow up visits. The proportion of patients for whom follow up was advised varied among providers from 11 to 100%. Independent associations with recommendation for follow up were limited to the identity and clinical volume of the provider, age of the patient, and the presence of multiple, small-to-moderate, or moderate mVSD. CONCLUSIONS: In this large series of moderate or smaller mVSD, pediatric cardiology follow up was commonly recommended but resulted in no active medical or surgical management. Major provider based inconsistency in intensity of follow up of mVSD was identified, but is difficult to justify.

Combination of real time three-dimensional echocardiography with diagnostic catheterization to derive left ventricular pressure-volume relations.

AIMS: The aim of this study was to investigate the left ventricular (LV) myocardial contractility index-Emax using transesophageal real time three-dimensional echocardiography (RT3DE) combined with catheterization. METHODS: Transesophageal RT3DE (single beat, X7-2 × matrix, iE33, Philips) was used to obtain real time LV volumes in pigs. Volumes were integrated with LV pressures from conductance catheterization (CC) to create RT3DE pressure-volume relations. At the same time, CC was used for measuring conventional pressure-volume relations that served as reference. The slope Emax was determined from RT3DE and CC end-systolic pressure-volume relations. All measurements were made at rest and during dobutamine infusion. RESULTS: In six pigs, the mean ± SD (mmHg/mL) values were Emax-CC 1.86 ± 1.1 and Emax-RT3DE 1.78 ± 1.2 (P = 0.502) at baseline. On dobutamine, mean Emax-CC was 3.43 ± 1.5 and Emax-RT3DE 3.60 ± 1.23 (P = 0.171). Bland-Altman analysis showed good agreements between the RT3DE- and CC-derived Emax for measurements performed at baseline and on dobutamine. CONCLUSIONS: Emax can be determined from RT3DE integrated with catheterization-derived pressures. RT3DE is a promising method for enhancing clinical applicability of pressure-volume relations for assessment of myocardial contractility.

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).

Validation of admittance computed left ventricular volumes against real-time three-dimensional echocardiography in the porcine heart.

The admittance and Wei's equation is a new technique for ventricular volumetry to determine pressure-volume relations that addresses traditional conductance-related issues of parallel conductance and field correction factor. These issues with conductance have prevented researchers from obtaining real-time absolute ventricular volumes. Moreover, the time-consuming steps involved in processing conductance catheter data warrant the need for a better catheter-based technique for ventricular volumetry. We aimed to compare the accuracy of left ventricular (LV) volumetry between the new admittance catheterization technique and transoesophageal real-time three-dimensional echocardiography (RT3DE) in a large-animal model. Eight anaesthetized pigs were used. A 7 French admittance catheter was positioned in the LV via the right carotid artery. The catheter was connected to an admittance control unit (ADVantage; Transonic Scisense Inc.), and data were recorded on a four-channel acquisition system (FA404; iWorx Systems). Admittance catheterization data and transoesophageal RT3DE (X7-2; Philips) data were simultaneously obtained with the animal ventilated, under neuromuscular blockade and monitored in baseline conditions and during dobutamine infusion. Left ventricular volumes measured from admittance catheterization (Labscribe; iWorx Systems) and RT3DE (Qlab; Philips) were compared. In a subset of four animals, admittance volumes were compared with those obtained from traditional conductance catheterization (MPVS Ultra; Millar Instruments). Of 37 sets of measurements compared, admittance- and RT3DE-derived LV volumes and ejection fractions at baseline and in the presence of dobutamine exhibited general agreement, with mean percentage intermethod differences of 10% for end-diastolic volumes, 14% for end-systolic volumes and 9% for ejection fraction; the respective intermethod differences between admittance and conductance in eight data sets compared were 11, 11 and 12%. Admittance volumes were generally higher than those obtained by RT3DE, especially among the larger ventricles. It is concluded that it is feasible to derive pressure-volume relations using admittance catheterization in large animals. This study demonstrated agreements between admittance and RT3DE to within 10-14% mean intermethod difference in the estimation of LV volumes. Further investigation will be required to examine the accuracy of volumes in largest ventricles, where intermethod divergence is greatest.