Three-Patch Reconstruction of Hourglass Supravalvar Pulmonary Artery Stenosis Mid-Term Results.

BACKGROUND: Some patients with pulmonary stenosis present with a complex multilevel disease that involves the valve, the leaflets, and the sinotubular junction (STJ) forming an hourglass appearance. We herein report the mid-term results of our experience with the reconstruction of the supravalvar narrowing using three pericardial patches. MATERIAL AND METHODS: Retrospective analysis of patient charts and echocardiography studies of patients who underwent three-patch reconstruction of the pulmonary valve (PV) from 2013 to 2022. After PV transection distal to STJ, vertical incisions into the sinuses were performed, and leaflets were trimmed and thinned. The three sinuses were augmented using three pericardial patches. RESULTS: Nineteen patients underwent repair of hourglass supravalvar pulmonary stenosis. Mean weight at surgery was 9.4 kg (median 7.2, range 4.7-35); 16 patients underwent previous catheterization with unsuccessful balloon dilatation of the PV (13 pts.). Preoperative aortic/pulmonary annulus ratio was 1.02 (median 1, range 0.89-1.25). After surgery, gradients across the PV were significantly reduced (94 ± 26 vs 29 ± 9 mm Hg, P = .02). Postoperatively, 14 patients had mild or no pulmonary insufficiency (PI) and five had mild to moderate PI. At a mean follow-up of 71 months (median 78 months, range 8-137), gradients continued to decrease (29 ± 9 vs 15 ± 5 mm Hg, P < .001). CONCLUSION: The three-patch technique for the repair of supravalvar pulmonary stenosis is simple, reproducible, and achieves excellent and long-standing relief of the right ventricular outflow tract gradient.

Pediatric Mechanical Circulatory Support: Introduction and Schneider's Experience.

BACKGROUND: Ventricular assist devices (VADs) play a critical and increasing role in treating end-stage heart failure in pediatric patients. A growing number of patients are supported by VADs as a bridge to heart transplantation. Experience with VADs in the pediatric population is limited, and experience in Israel has not been published. OBJECTIVES: To describe this life-saving technology and our experience with VAD implantation in children with heart failure, including characteristics and outcomes. METHODS: We conducted a retrospective chart review of all patients who underwent VAD implantation at Schneider Children's Medical Center from 2018 to 2023. RESULTS: We analyzed results of 15 children who underwent VAD implantation. The youngest was 2.5 years old and weighed 11 kg at implantation. In eight patients, HeartMate 3, a continuous-flow device, was implanted. Seven patients received Berlin Heart, a pulsatile-flow device. Three children required biventricular support; 11 underwent heart transplants after a median duration of 169 days. Two patients died due to complications while awaiting a transplant; two were still on VAD support at the time of submission of this article. Successful VAD support was achieved in 86.6% of patients. In the last 5 years,79% of our heart transplant patients received VAD support prior to transplant. CONCLUSIONS: Circulatory assist devices are an excellent bridge to transplantation for pediatric patients reaching end-stage heart failure. VADs should be carefully selected, and implantation techniques tailored to patient's weight and diagnosis at a centralized pediatric cardiac transplantation center. Israeli healthcare providers should be cognizant of this therapeutic alternative.

Low Risk of Inappropriate Shock Among Pediatric Patients With an Implantable Cardioverter Defibrillator: A Single Center Experience.

Implantable cardioverter-defibrillators (ICD) are increasingly being used among the pediatric population for indications of both primary and secondary prevention. There is limited long-term data on the outcomes of pediatric patients following ICD implantation. The aim of this study was to investigate the characteristics of this population, burden of appropriate and inappropriate shock and complication rate in a large tertiary pediatric medical center. Included were children under the age of 18 years who underwent ICD implantation and had clinical follow up at our center. Data were retrospectively collected between study period 2005-2020. Primary outcome was the incidence of ICD shock appropriate and inappropriate. Secondary outcome was defining our patient population characteristics. Our cohort included 51 patients who underwent ICD implantation. Mean age at implantation was 10.9 ± 4.7 years and average follow-up time was 67 months. Diagnoses of implanted patients were: 28 (55%) patients with syndromes with risk for sudden death, cardiomyopathy in 14 patients (27%) and congenital heart disease (CHD) in 9 patients (18%). Forty-two (82%) patients had an ICD implanted for secondary prevention after experiencing a life-threatening arrhythmia and 9 (18%) for primary prevention. An endocardial system was implanted in 39 (76%) patients and an epicardial systems in 12 (24%) patients. A total of 20 (39%) patients received appropriate shocks for ventricular fibrillation(VF). 5 patients received inappropriate shocks, 4 due to sinus tachycardia and 1 due to rapidly conducted atrial fibrillation. Those who received an inappropriate shock had a significantly shorter ICD-programmed VF detection cycle length compared to those who did not receive an inappropriate shock (320 ms versus 270 ms, p = 0.062). This single center study demonstrates a high rate of appropriate ICD shocks (39%) and a low rate of inappropriate ICD shocks. Accurate programming of ICD devices in the pediatric population is paramount to avoid inappropriate ICD shocks.

The Amplatzer duct occluder (ADOII) and Piccolo devices for patent ductus arteriosus closure: a large single institution series.

Purpose: Evaluate Piccolo and ADOII devices for transcatheter patent ductus arteriosus (PDA) closure. Piccolo has smaller retention discs reducing risk of flow disturbance but residual leak and embolization risk may increase. Methods: Retrospective review of all patients undergoing PDA closure with an Amplatzer device between January 2008 and April 2022 in our institution. Data from the procedure and 6 months follow-up were collected. Results: 762 patients, median age 2.6 years (range 0-46.7) years and median weight 13 kg (range 3.5-92) were referred for PDA closure. Overall, 758 (99.5%) had successful implantation: 296 (38.8%) with ADOII, 418 (54.8%) with Piccolo, and 44 (5.8%) with AVPII. The ADOII patients were smaller than the Piccolo patients (15.8 vs. 20.5 kg, p < 0.001) and with larger PDA diameters (2.3 vs. 1.9 mm, p < 0.001). Mean device diameter was similar for both groups. Closure rate at follow-up was similar for all devices ADOII 295/296 (99.6%), Piccolo 417/418 (99.7%), and AVPII 44/44 (100%). Four intraprocedural embolizations occurred during the study time period: two ADOII and two Piccolo. Following retrieval the PDA was closed with an AVPII in two cases, ADOI in one case and with surgery in the fourth case. Mild stenosis of the left pulmonary artery (LPA) occurred in three patients with ADOII devices (1%) and one patient with Piccolo device (0.2%). Severe LPA stenosis occurred in one patient with ADOII (0.3%) and one with AVPII device (2.2%). Conclusions: ADOII and Piccolo are safe and effective for PDA closure with a tendency to less LPA stenosis with Piccolo. There were no cases of aortic coarctation related to a PDA device in this study.

Vigilance in the Decision-Making Process Regarding Termination of Pregnancy Following Prenatal Diagnosis of Congenital Heart Disease-Application of the 'Conflict Decision-Making Model'.

The decision-making process regarding termination of pregnancy following prenatal diagnosis of congenital heart disease is a stressful experience for future parents. Janis and Mann's conflict decision-making model describes seven ideal stages that comprise vigilant information-gathering as an expression of the qualitative decision-making process. In our study, we attempted to determine whether parents who face the decision regarding termination of pregnancy undertake a qualitative decision-making process. Data were collected over 2-year period using structural questionnaires. The sample consisted of two hundred forty participants; sixty-nine (28.75%) declared that their decision was to terminate the pregnancy. A significant difference in the quality of the decision-making score was noted between parents who decided to continue with the pregnancy vs. parents who opted for termination (mean score of 10.15 (5.6) vs. 18.51 (3.9), respectively, p < 0.001). Sixty-two (90%) participants within the termination of pregnancy group went through all seven stages of vigilant decision-making process and utilized additional sources for information and consultation. Parents who decided to continue with the pregnancy made swift decisions, often without considering the negative and positive outcomes; this decision-making pattern is considered non-vigilant and ineffective. Identification of future parents at risk of going through an ineffective decision-making process may help health professionals to determine the best way to provide them with information and support.

Transthoracic intracardiac lines-A double edged sword.

OBJECTIVE: Routine use of central venous access is needed in children undergoing open heart surgery for pressure monitoring and inotrope infusion. We sought to evaluate the efficiency and safety of routine use of transthoracic intracardiac lines (ICLs) in patients undergoing cardiac surgery and to compare them to patients who have been previously treated with traditional central venous lines (non-ICLs). METHODS: Retrospective review of charts of all patients who underwent cardiac surgery and had an ICL inserted in the operating room. Case control matching was done with similar patient in which ICL was not inserted. Patients characteristics, diagnosis, operative, and intensive care data were collected for each patient and analyzed. RESULTS: A total number of 376 patient records were reviewed (198 ICL patients and 178 non-ICL patients). Umbilical line and non-ICL durations were longer in the non-ICL group. ICL duration was the longest of all lines, averaging 12.87 ± 10.82 days. The necessity for multiple line insertions (˃2 insertions) was significantly higher in the non-ICL group, with a relative risk ratio of 3.24 (95% confidence interval: 1.617-6.428). There was no statistical difference of infections rate and line complications between the two groups. CONCLUSION: ICLs are safe in infants undergoing cardiac surgery and can be kept in place for a long period of time with a low rate of line complications and infection. Routine use of ICLs reduces the number of central venous catheter placement in this complex patient population.

Autoantibodies against interleukin-1 receptor antagonist in multisystem inflammatory syndrome in children: a multicentre, retrospective, cohort study.

Background: Multisystem inflammatory syndrome in children (MIS-C) is a rare but serious complication of infection with SARS-CoV-2. A possible involvement of pathogenetically relevant autoantibodies has been discussed. Recently, neutralising autoantibodies against inflammatory receptor antagonists progranulin and interleukin-1 receptor antagonist (IL-1Ra) were found in adult patients with critical COVID-19. The aim of this study was to investigate the role of such autoantibodies in MIS-C. Methods: In this multicentre, retrospective, cohort study, plasma and serum samples were collected from patients (0-18 years) with MIS-C (as per WHO criteria) treated at five clinical centres in Germany and Spain. As controls, we included plasma or serum samples from children with Kawasaki disease, children with inactive systemic juvenile idiopathic arthritis, and children with suspected growth retardation (non-inflammatory control) across four clinical centres in Germany and Spain (all aged ≤18 years). Serum samples from the CoKiBa trial were used as two further control groups, from healthy children (negative for SARS-CoV-2 antibodies) and children with previous mild or asymptomatic COVID-19 (aged ≤17 years). MIS-C and control samples were analysed for autoantibodies against IL-1Ra and progranulin, and for IL-1Ra concentrations, by ELISA. Biochemical analysis of plasma IL-1Ra was performed with native Western blots and isoelectric focusing. Functional activity of the autoantibodies was examined by an in vitro IL-1ß-signalling reporter assay. Findings: Serum and plasma samples were collected between March 6, 2011, and June 2, 2021. Autoantibodies against IL-1Ra could be detected in 13 (62%) of 21 patients with MIS-C (11 girls and ten boys), but not in children with Kawasaki disease (n=24; nine girls and 15 boys), asymptomatic or mild COVID-19 (n=146; 72 girls and 74 boys), inactive systemic juvenile idiopathic arthritis (n=10; five girls and five boys), suspected growth retardation (n=33; 13 girls and 20 boys), or in healthy controls (n=462; 230 girls and 232 boys). Anti-IL-1Ra antibodies in patients with MIS-C belonged exclusively to the IgG1 subclass, except in one patient who had additional IL-1Ra-specific IgM antibodies. Autoantibodies against progranulin were only detected in one (5%) patient with MIS-C. In patients with MIS-C who were positive for anti-IL-1Ra antibodies, free plasma IL-1Ra concentrations were reduced, and immune-complexes of IL-1Ra were detected. Notably, an additional, hyperphosphorylated, transiently occurring atypical isoform of IL-1Ra was observed in all patients with MIS-C who were positive for anti-IL-1Ra antibodies. Anti-IL-1Ra antibodies impaired IL-1Ra function in reporter cell assays, resulting in amplified IL-1ß signalling. Interpretation: Anti-IL-1Ra autoantibodies were observed in a high proportion of patients with MIS-C and were specific to these patients. Generation of these autoantibodies might be triggered by an atypical, hyperphosphorylated isoform of IL-1Ra. These autoantibodies impair IL-1Ra bioactivity and might thus contribute to increased IL-1ß-signalling in MIS-C. Funding: NanoBioMed fund of the University of Saarland, José Carreras Center for Immuno and Gene Therapy, Dr Rolf M Schwiete Stiftung, Staatskanzlei Saarland, German Heart Foundation, Charity of the Blue Sisters, Bavarian Ministry of Health, the Center for Interdisciplinary Clinical Research at University Hospital Münster, EU Horizon 2020.

CMR Imaging 6 Months After Myocarditis Associated with the BNT162b2 mRNA COVID-19 Vaccine.

Temporal association between BNT162b2 mRNA COVID-19 vaccine and myocarditis (PCVM) has been reported. We herein present early and 6-month clinical follow-up and cardiac magnetic resonance imaging (CMR) of patients with PVCM. A retrospective collection of data from 15 patients with PCVM and abnormal CMR was performed. Clinical manifestation, laboratory data, hospitalizations, treatment protocols, and imaging studies were collected early (up to 2 months) and later. In nine patients, an additional CMR evaluation was performed 6 months after diagnosis. PCVM was diagnosed in 15 patients, mean age 17 ± 1 (median 17.2, range 14.9-19 years) years, predominantly in males. Mean time from vaccination to onset of symptoms was 4.4 ± 6.7 (median 3, range 0-28) days. All patients had CMR post diagnosis at 4 ± 3 (median 3, range 1-9) weeks, 4/5 patients had hyper enhancement on the T2 sequences representing edemaQuery, and 12 pathological Late glandolinium enhancement. A repeat scan performed after 5-6 months was positive for scar formation in 7/9 patients. PCVM is a rare complication, affecting predominantly males and appearing usually within the first week after administration of the second dose of the vaccine. It usually is a mild disease, with clinical resolution with anti-inflammatory treatment. Late CMR follow up demonstrated resolution of the edema in all patients, while some had evidence of residual myocardial scarring.

Large diameter Advanta V12 covered stent trial for coarctation of the aorta: COARC Study

BACKGROUND: Covered stent implantation for treatment of coarctation of the aorta (CoA) is effective and can prevent aortic wall injury. Prospective studies with long-term follow-up, including imaging, are lacking. We report the acute and long-term outcomes for use of the Large Diameter Advanta V12 covered stent for treatment of native and recurrent CoA. METHODS: A prospective, multicenter, nonrandomized study was performed including 70 patients (43 male), median age 17 years, median weight 57.4 kg with CoA who underwent implantation of the Large Diameter Advanta V12 covered stent. Annual follow-up for 5 years included Doppler echocardiography to calculate diastolic velocity: systolic velocity ratio. RESULTS: CoA diameter increased from 5.6±3.6 to 14.9±3.9 mm (P<0.0001) and the pressure gradient decreased from 35.8±16.2 to 5.6±7.9 mm Hg (P<0.0001). Preimplantation diastolic velocity: systolic velocity of 0.6±0.16 dropped to 0.34±0.13 (P<0.0001) and was maintained at 5 years. Computed tomography angiograms at 12 months post implantation demonstrated the stent: transverse arch diameter to be similar, 0.91±0.09 to post procedure 0.86±0.14. Major adverse vascular events at 30 days and 12 months were 1.4% and 4.3%, respectively. Significant adverse events included three patients who required stent implantation to treat infolding. There were no mortalities. CONCLUSIONS: The Large Diameter Advanta V12 covered stent is safe and effective for the treatment of CoA with an immediate and sustained reduction of the pressure gradient over 12 months and 5 years as assessed by preimplantation and post implantation Doppler echocardiography and 12-month computed tomography angiography.

Large Diameter Advanta V12 Covered Stent Trial for Coarctation of the Aorta: COARC Study.

BACKGROUND: Covered stent implantation for treatment of coarctation of the aorta (CoA) is effective and can prevent aortic wall injury. Prospective studies with long-term follow-up, including imaging, are lacking. We report the acute and long-term outcomes for use of the Large Diameter Advanta V12 covered stent for treatment of native and recurrent CoA. METHODS: A prospective, multicenter, nonrandomized study was performed including 70 patients (43 male), median age 17 years, median weight 57.4 kg with CoA who underwent implantation of the Large Diameter Advanta V12 covered stent. Annual follow-up for 5 years included Doppler echocardiography to calculate diastolic velocity: systolic velocity ratio. RESULTS: CoA diameter increased from 5.6±3.6 to 14.9±3.9 mm (P<0.0001) and the pressure gradient decreased from 35.8±16.2 to 5.6±7.9 mm Hg (P<0.0001). Preimplantation diastolic velocity:systolic velocity of 0.6±0.16 dropped to 0.34±0.13 (P<0.0001) and was maintained at 5 years. Computed tomography angiograms at 12 months postimplantation demonstrated the stent:transverse arch diameter to be similar, 0.91±0.09 to postprocedure 0.86±0.14. Major adverse vascular events at 30 days and 12 months were 1.4% and 4.3%, respectively. Significant adverse events included three patients who required stent implantation to treat infolding. There were no mortalities. CONCLUSIONS: The Large Diameter Advanta V12 covered stent is safe and effective for the treatment of CoA with an immediate and sustained reduction of the pressure gradient over 12 months and 5 years as assessed by preimplantation and postimplantation Doppler echocardiography and 12-month computed tomography angiography. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00978952. URL: http://www.anzctr.org.au; Unique identifier: ACTRN12612000013864.

Mid-term results of vascular ring surgery.

BACKGROUND: Vascular rings cause respiratory symptoms in children. Treatment consists of surgical division; however, data regarding mid-term results are scarce. The purpose of this study was to evaluate clinical results of vascular ring surgery. METHODS: Retrospective chart review of consecutive patients who underwent vascular ring surgery. Mid-term follow-up consisted of clinic visits and telephone questionnaire over a 1-year period sampling at five points in time. RESULTS: Follow-up of 85 patients who underwent vascular rings surgery revealed significant symptomatic improvement within 6 months. In total, 50% were symptomatic to some degree at their last documented clinic visit complaining of stridor (36.8%), cough (34.2%), wheezing (10.5%), dyspnoea on exertion (10.5%), or recurrent respiratory infections (23.7%). By telephone questionnaires, 83% described a significant improvement in respiratory symptoms, 63.4% had some residual symptoms, 36.6% stridor, 38.8% chronic cough, 32.4% bronchodilator use,18.3% had at least one episode of pneumonia per year, 31% of children had dyspnoea or respiratory limitation, and 12.7% while doing physical activities. We found no association between the age at surgery or anatomic variant to the presence of symptoms at mid-term follow-up. CONCLUSIONS: Surgical division of vascular rings results in significant clinical improvement within 1 year; nevertheless, some patients remain symptomatic to some degree. We found no association between the age at surgery or anatomic variant to the presence of symptoms at mid-term follow-up. Further evaluation is warranted to assess the nature of residual symptoms and explore whether anatomical causes can be identified leading to surgical modifications.

Long COVID in Children: Observations From a Designated Pediatric Clinic.

Systematic data are lacking on pediatric long COVID. This study prospectively assessed 90 children with persistent symptoms who presented to a designated multidisciplinary clinic for long COVID. In nearly 60%, symptoms were associated with functional impairment at 1-7 months after the onset of infection. A comprehensive structured evaluation revealed mild abnormal findings in approximately half the patients, mainly in the respiratory aspect.

Complex Catheter-Based Structural Heart Reconstruction in a Patient With Tricuspid Atresia and Björk Palliative Conduit.

Björk conduit failure is a common reason for reintervention after a Björk modification of the Fontan procedure. We describe a first performed in human percutaneous procedure for the treatment of a failing Björk circuit in an adult with congenital heart disease and complex anatomic features. (Level of Difficulty: Advanced.).

Factors That Influence Parents' Decision-Making Regarding Termination of Pregnancy After Prenatal Diagnosis of Fetal Congenital Heart Disease.

OBJECTIVE: To explore factors that influence parents' decisions regarding the termination of pregnancy after the detection of fetal congenital heart disease (CHD). DESIGN: A prospective descriptive study. SETTING: The Institute of Pediatric Cardiology in the Schneider Children's Medical Center. PARTICIPANTS: One hundred twenty couples (240 participants) with fetuses prenatally diagnosed with CHD, which was defined as conditions requiring surgical treatment. METHODS: We obtained data from a structured questionnaire for the pediatric cardiologist, the medical records, and structured self-report questionnaires for the participants. RESULTS: Thirty-six of 120 couples (30%) decided to terminate the pregnancy after a prenatal diagnosis of fetal CHD. The main factors associated with the decision to terminate were low gestational age (OR = 0.83 per week, 95% confidence interval [CI] [0.75, 0.96]), severe cardiac malformation (OR = 2.23, 95% CI [1.40, 3.53]), religious affiliation (OR = 10.0 for secular participants vs. others, 95% CI [4.61, 22.46], population group (OR = 2.96 for Jewish participants vs. others, 95% CI [1.63, 11.3]), and education (OR = 1.34 per year of education, 95% CI [1.15, 1.55]). CONCLUSIONS: Our findings describe the profiles of couples who decided to terminate their pregnancies after a prenatal diagnosis of fetal CHD. Early identification of the couple's decision can help health care providers provide adequate support, counseling, and guidance. Future research is needed to understand parents' needs for support through the process of decision-making, with attention to their religious and cultural values and contexts.

Clinical Features and Comparison of Kingella and Non-Kingella Endocarditis in Children, Israel.

Kingella spp. have emerged as an important cause of invasive pediatric diseases. Data on Kingella infective endocarditis (KIE) in children are scarce. We compared the clinical features of pediatric KIE cases with those of Streptococcus species IE (StIE) and Staphylococcus aureus IE (SaIE). A total of 60 patients were included in the study. Throughout the study period, a rise in incidence of KIE was noted. KIE patients were significantly younger than those with StIE and SaIE, were predominately boys, and had higher temperature at admission, history of oral aphthae before IE diagnosis, and higher lymphocyte count (p<0.05). Pediatric KIE exhibits unique features compared with StIE and SaIE. Therefore, in young healthy children <36 months of age, especially boys, with or without a congenital heart defect, with a recent history of oral aphthae, and experiencing signs and symptoms compatible with endocarditis, Kingella should be suspected as the causative pathogen.

Extracorporeal Membrane Oxygenation as a Rescue Therapy for Postoperative Diastolic Dysfunction and Refractory Chylothorax.

This is the first published case, as far as we know, of a term neonate with refractory chylothorax secondary to diastolic dysfunction in the cardiac postoperative period, where extracorporeal membrane oxygenation (ECMO) was used to improve the physiologic derangements, thus allowing resolution of the chylous effusion. The infant was prenatally diagnosed with d-transposition of the great arteries. He was started on prostaglandin infusion and underwent balloon atrial septostomy followed by arterial switch operation. After surgery, he developed anasarca and high-volume chylothorax that did not respond to medical management and fasting. Cardiac catheterization demonstrated severe diastolic dysfunction and pulmonary hypertension. On postoperative day 19, he was placed on veno-arterial (VA) ECMO and had gradual regression of the chylothorax and edema. After 13 days on ECMO support, he was decannulated with small, self-limiting, reaccumulation of chylous effusion. He was discharged home on postoperative day 57, and has since been thriving with no evidence of reaccumulation of the chylous effusion. In summary, VA ECMO support could be considered as a rescue modality for patients with uncontrollable refractory high-volume chylous effusion, after other treatment options have been pursued.

Ultrasound Cardiac Output Monitor (USCOM™) Measurements Prove Unreliable Compared to Cardiac Magnetic Resonance Imaging in Adolescents with Cardiac Disease.

The purpose of this stuy is to prospectively assess the reliability of the ultrasound cardiac output monitor (USCOM™) for measuring stroke volume index and predicting left ventricular outflow tract diameter in adolescents with heart disease. Sixty consecutive adolescents with heart disease attending a tertiary medical center underwent USCOM™ assessment immediately after cardiac magnetic resonance imaging. USCOM™ measured stroke volume index and predicted left ventricular outflow tract diameter were compared to cardiac magnetic resonance imaging-derived values using Bland-Altman analysis. Ten patients with an abnormal left ventricular outflow tract were excluded from the analysis. An adequate USCOM™ signal was obtained in 49/50 patients. Mean stroke volume index was 46.1 ml/m2 by the USCOM™ (range 22-66.9 ml/m2) and 42.9 ml/m2 by cardiac magnetic resonance imaging (range 24.7-59.9 ml/m2). The bias (mean difference) was 3.2 ml/m2; precision (± 2SD of differences), 17 ml/m2; and mean percentage error, 38%. The mean (± 2SD) left ventricular outflow tract diameter was 0.445 ± 0.536 cm smaller by the USCOM™ algorithm prediction than by cardiac magnetic resonance imaging. Attempted adjustment of USCOM™ stroke volume index using cardiac magnetic resonance imaging left ventricular outflow tract diameter failed to improve agreement between the two modalities (bias 28.4 ml/m2, precision 44.1 ml/m2, percentage error 77.3%). Our study raises concerns regarding the reliability of USCOM™ for stroke volume index measurement in adolescents with cardiac disease, which did not improve even after adjusting for its inaccurate left ventricular outflow tract diameter prediction.