Prenatal Diagnosis of Congenital Heart Disease: The Crucial Role of Perinatal and Delivery Planning.

Although most congenital heart defects (CHDs) are asymptomatic at birth, certain CHD lesions are at significant risk of severe hemodynamic instability and death if emergent cardiac interventions are not performed in a timely fashion. Therefore, accurate identification of at-risk fetuses and appropriate delivery resource planning according to the degree of anticipated hemodynamic instability is crucial. Fetal echocardiography has increased prenatal CHD detection in recent years due to advancements in ultrasound techniques and improved obstetrical cardiac screening protocols, enabling the prediction of newborns' hemodynamic status. This assessment can guide multidisciplinary resource planning for postnatal care, including selection of delivery site, delivery room management, and transport to a cardiac center based on CHD risk severity. This review will discuss fetal cardiovascular physiology and the circulatory changes that occur at the time of and immediately following birth, outline fetal echocardiographic findings used to risk-stratify newborns with CHDs, and outline principles for neonatal resuscitation and initial transitional care in neonates with these complex CHD lesions.

Prevalence of pulmonary hypertension in obstructive sleep apnea and relation to disease severity.

STUDY OBJECTIVES: The purpose of this study is to examine the prevalence of pulmonary hypertension (PHTN) in children with obstructive sleep apnea (OSA) using echocardiographic (ECHO) parameters and to examine ECHO findings as they relate to severity of OSA. METHODS: A retrospective cohort study of subjects with OSA undergoing polysomnogram (PSG) and ECHO within 30 days of each other, between 01/01/15 - 12/31/20 was performed, excluding cardiac disease. ECHO evidence of PHTN was defined as ≥ 2 of the following: tricuspid regurgitation (TR) velocity > 3.0 m/sec, pulmonary acceleration/ejection time (AT/ET) ratio < 0.3, left ventricular eccentricity index (EI) > 1.5, right ventricular (RV) dysfunction or abnormal geometry. ECHO parameters were compared to OSA severity using obstructive apnea-hypopnea index (AHI), % time with oxygen saturation < 90%, and % time with end-tidal carbon dioxide > 50 mmHg. Odds ratios were calculated for each comorbidity to evaluate for risk factors. RESULTS: Of 509 subjects, 4.3% were found to have echocardiographic evidence of PHTN. Neither oAHI severity, nor worsening hypoxemia or hypercarbia correlated with worsening ECHO parameters. Comorbidities including bronchopulmonary dysplasia (OR 5.22, 2.01 - 13.53), prematurity (OR 3.10, 1.28 - 7.47), and autism (OR 3.69, 1.01 - 13.49) were associated with increased odds of PHTN. CONCLUSIONS: Significant echocardiographic evidence of PHTN was seen in 4.3% of children with OSA. ECHO findings of PHTN did not correlate with PSG parameters. Comorbidities, particularly bronchopulmonary dysplasia, prematurity, and autism, appear to be a risk factor for developing PHTN in patients with OSA.

Congenitally Corrected Transposition of the Great Arteries: Fetal Diagnosis, Associations, and Postnatal Outcome: A Fetal Heart Society Research Collaborative Study.

Background Fetal diagnosis of congenitally corrected transposition of the great arteries (ccTGA) has been increasingly reported; however, predictors of clinical outcomes remain underexplored. We undertook a multicenter, retrospective study to investigate natural history, associated anomalies, and outcomes of fetal ccTGA. Methods and Results Fetuses with ccTGA diagnosed from January 2004 to July 2020 within 20 North American programs were included. Fetuses with severe ventricular hypoplasia thought to definitively preclude biventricular repair were excluded. We included 205 fetuses diagnosed with ccTGA at a median gestational age of 23 (interquartile range, 21-27) weeks. Genetic abnormalities were found in 5.9% tested, with extracardiac anomalies in 6.3%. Associated cardiac defects were diagnosed in 161 (78.5%), with atrioventricular block in 23 (11.3%). On serial fetal echocardiogram, 39% demonstrated a functional or anatomic change, most commonly increased tricuspid regurgitation (6.7%) or pulmonary outflow obstruction (11.1%). Of 194 fetuses with follow-up, 26 were terminated, 3 experienced fetal death (2 with atrioventricular block), and 165 were live-born. Of 158 with postnatal data (median follow-up 3.7 years), 10 (6.6%) had death/transplant before 1 year. On univariable analysis, fetal factors associated with fetal death or death/transplant by 1 year included ≥ mild tricuspid regurgitation, pulmonary atresia, aortic obstruction, fetal arrhythmia, and worsening hemodynamics on serial fetal echocardiogram (defined as worse right ventricular function, tricuspid regurgitation, or effusion). Conclusions Associated cardiac lesions and arrhythmias are common in fetal ccTGA, and functional changes commonly occur through gestation. Worse outcomes are associated with fetal tricuspid regurgitation (≥mild), any arrhythmia, pulmonary atresia, aortic obstruction, and worsening hemodynamics on serial echocardiograms. These findings can inform prenatal counseling and perinatal management planning.

Contemporary Outcomes in Fetuses Diagnosed with Vascular Rings.

Vascular rings are increasingly identified on fetal echocardiography. The purpose of this study is to analyze clinical outcomes and patterns of diagnostic testing in fetuses with vascular rings diagnosed by echocardiography. A retrospective cohort study was performed of fetuses with postnatally confirmed vascular rings from 2017 to 2022. Clinical outcomes included type and timing of symptoms, and timing of surgical intervention. Freedom from symptoms and/or surgery was assessed by Kaplan-Meier analysis. Frequency of genetic and diagnostic testing (barium esophagogram, CT/MRI angiogram, and bronchoscopy) was also assessed. Overall, 46 patients were evaluated (91% with a right aortic arch/left ductus and 4% with a double aortic arch). A vascular ring was isolated in 59%, associated with structural heart lesions in 33%, and associated with noncardiac anomalies in 8%. Prenatal diagnoses increased over time. Symptoms developed in 24% (11/46); 82% (9/11) had respiratory and 45% (5/11) had gastroesophageal complaints. Surgery was performed in 17% (11/46). Symptoms presented bimodally, prior to 100 or after 400 days of life. There was no difference in the type of symptoms for early (< 100 days) or late (> 400 days) presenters. Symptomatic patients received more diagnostic testing. Genetic testing was obtained in 46% and positive in 33%, with 22q11 deletion and Trisomy 21 being identified. Prenatal diagnoses of vascular rings increased over time, with subjects developing symptoms bimodally in early or late infancy. The frequency of genetic testing was suboptimal given the prevalence of genetic abnormalities seen in this population.

Evaluation of Left Ventricular Outflow Gradients During Staged Exercise Stress Echocardiography Helps Differentiate Pediatric Patients With Hypertrophic Cardiomyopathy From Athletes and Normal Subjects.

BACKGROUND: Elevated left ventricular outflow tract (LVOT) gradients during exercise can occur in patients with hypertrophic cardiomyopathy (HCM) as well as in athletes and normal controls. The authors' staged exercise protocol calls for imaging at rest and during each stage of exercise to evaluate the mechanism of LVOT obstruction at each stage. They investigated whether this staged approach helps differentiate HCM from athletes and normal controls. METHODS: They reviewed pediatric exercise stress echocardiograms completed between January 2009 and October 2017 at their center and identified those with gene-positive HCM, athlete's heart, and normal controls. Children with inducible obstruction (those with no LVOT gradient at rest who developed a LVOT peak gradient > 25 mm Hg during exercise) were included. LVOT peak gradient, velocity time integral, acceleration time, and deceleration time were measured at rest, submaximal stages, and peak exercise. RESULTS: Compared with athletes, HCM patients had significantly higher LVOT peak gradients at rest (P = .019), stage 1 of exercise (P = .002), and peak exercise (P = .051), as well as a significantly higher change in LVOT peak gradient from rest to stage 1 (P = .016) and from rest to peak (P = .038). The acceleration time/deceleration time ratio of the LVOT Doppler was significantly lower in HCM patients compared with normal controls at peak exercise. CONCLUSIONS: The HCM patients who develop elevated LVOT gradients at peak exercise typically manifest early obstruction in the submaximal stages of exercise, which helps to differentiate them from athletes and normal controls.

Impact of Socioeconomic Status, Race and Ethnicity, and Geography on Prenatal Detection of Hypoplastic Left Heart Syndrome and Transposition of the Great Arteries.

BACKGROUND: Prenatal detection (PND) has benefits for infants with hypoplastic left heart syndrome (HLHS) and transposition of the great arteries (TGA), but associations between sociodemographic and geographic factors with PND have not been sufficiently explored. This study evaluated whether socioeconomic quartile (SEQ), public insurance, race and ethnicity, rural residence, and distance of residence (distance and driving time from a cardiac surgical center) are associated with the PND or timing of PND, with a secondary aim to analyze differences between the United States and Canada. METHODS: In this retrospective cohort study, fetuses and infants <2 months of age with HLHS or TGA admitted between 2012 and 2016 to participating Fetal Heart Society Research Collaborative institutions in the United States and Canada were included. SEQ, rural residence, and distance of residence were derived using maternal census tract from the maternal address at first visit. Subjects were assigned a SEQ z score using the neighborhood summary score or Canadian Chan index and separated into quartiles. Insurance type and self-reported race and ethnicity were obtained from medical charts. We evaluated associations among SEQ, insurance type, race and ethnicity, rural residence, and distance of residence with PND of HLHS and TGA (aggregate and individually) using bivariate analysis with adjusted associations for confounding variables and cluster analysis for centers. RESULTS: Data on 1862 subjects (HLHS: n=1171, 92% PND; TGA: n=691, 58% PND) were submitted by 21 centers (19 in the United States). In the United States, lower SEQ was associated with lower PND in HLHS and TGA, with the strongest association in the lower SEQ of pregnancies with fetal TGA (quartile 1, 0.78 [95% CI, 0.64-0.85], quartile 2, 0.77 [95% CI, 0.64-0.93], quartile 3, 0.83 [95% CI, 0.69-1.00], quartile 4, reference). Hispanic ethnicity (relative risk, 0.85 [95% CI, 0.72-0.99]) and rural residence (relative risk, 0.78 [95% CI, 0.64-0.95]) were also associated with lower PND in TGA. Lower SEQ was associated with later PND overall; in the United States, rural residence and public insurance were also associated with later PND. CONCLUSIONS: We demonstrate that lower SEQ, Hispanic ethnicity, and rural residence are associated with decreased PND for TGA, with lower SEQ also being associated with decreased PND for HLHS. Future work to increase PND should be considered in these specific populations.

Risk Factors for Mortality and Circulatory Outcome Among Neonates Prenatally Diagnosed With Ebstein Anomaly or Tricuspid Valve Dysplasia: A Multicenter Study.

Background In a recent multicenter study of perinatal outcome in fetuses with Ebstein anomaly or tricuspid valve dysplasia, we found that one third of live-born patients died before hospital discharge. We sought to further describe postnatal management strategies and to define risk factors for neonatal mortality and circulatory outcome at discharge. Methods and Results This 23-center, retrospective study from 2005 to 2011 included 243 fetuses with Ebstein anomaly or tricuspid valve dysplasia. Among live-born patients, clinical and echocardiographic factors were evaluated for association with neonatal mortality and palliated versus biventricular circulation at discharge. Of 176 live-born patients, 7 received comfort care, 11 died <24 hours after birth, and 4 had insufficient data. Among 154 remaining patients, 38 (25%) did not survive to discharge. Nearly half (46%) underwent intervention. Mortality differed by procedure; no deaths occurred in patients who underwent right ventricular exclusion. At discharge, 56% of the cohort had a biventricular circulation (13% following intervention) and 19% were palliated. Lower tricuspid regurgitation jet velocity (odds ratio [OR], 2.3 [1.1-5.0], 95% CI, per m/s; P=0.025) and lack of antegrade flow across the pulmonary valve (OR, 4.5 [1.3-14.2]; P=0.015) were associated with neonatal mortality by multivariable logistic regression. These variables, along with smaller pulmonary valve dimension, were also associated with a palliated outcome. Conclusions Among neonates with Ebstein anomaly or tricuspid valve dysplasia diagnosed in utero, a variety of management strategies were used across centers, with poor outcomes overall. High-risk patients with low tricuspid regurgitation jet velocity and no antegrade pulmonary blood flow should be considered for right ventricular exclusion to optimize their chance of survival.

Test-retest variability for quantitative two-dimensional and Doppler measurements in the fetus.

OBJECTIVES: Echocardiography is used to quantitatively characterize cardiovascular function in fetuses with cardiac abnormalities and inform decisions for fetal or perinatal interventions. It is clinically important to understand the reproducibility of these measures, particularly between testers. While studies have reported intra-observer variability and inter-observer variability, little is known about test-retest variability for these measures. We hypothesized that even in a high volume echocardiography laboratory, quantitative measurements will demonstrate higher test-retest variability compared with inter-observer variability and intra-observer variability of the same measurements. METHODS: Prospective study of uncomplicated, singleton pregnancies to evaluate fetal measures of cardiovascular function obtained by echocardiography. One sonographer obtained predefined variables, and then, a second sonographer obtained the same variables 15 minutes after the first sonographer. Separate data acquisitions were obtained by the two sonographers to evaluate test-retest variability. Intra-observer variability and inter-observer variability were also evaluated. RESULTS: Thirty fetuses between 17- and 36-week gestation were enrolled. Time-based variables had the best intra-observer agreement and inter-observer agreement (1.2%-7.4%), while 2D (7.5%-10%), M-mode (4.9%-10.1%), and velocity-time integral (VTI; 2.6%-13.8%) measurements had poorer agreement. For all variables, test-retest agreement was worse (3%-32.1%), particularly for measurement of myocardial performance index (MPI; 19.7%-21.1%), cardiac output estimation (27.2%-27.9%), and VTI-based indices (14.7%-32.1%). CONCLUSIONS: In a laboratory highly experienced in quantitative fetal echocardiography, intra-observer agreement and inter-observer agreement are good for most quantitative parameters. However, test-retest agreement is fair or poor for several variables, notably the MPI, cardiac output estimation, and VTI-based indices. Understanding how these measures vary between separate acquisitions is important for clinical interpretation and decision making.

Preoperative Aortic Arch Size and Late Outcome After Coarctation Repair by Lateral Thoracotomy.

BACKGROUND: The approach (lateral thoracotomy versus median sternotomy) to repair coarctation of the aorta is frequently based on arch dimensions from the preoperative echocardiogram. Few studies have assessed the relationship between preoperative arch dimensions and late postoperative outcome. This study aimed to define how preoperative arch dimensions relate to late outcomes and identify long-term predictors of a successful operation. METHODS: We performed a retrospective review of 102 neonates and infants undergoing isolated coarctation repair by lateral thoracotomy between 2003 and 2012. Long-term surgical success was defined based on the following five factors: corrected arch gradient below 20 mm Hg, blood pressure cuff gradient below 15 mm Hg, systolic blood pressure below the 95th percentile during the clinic visit, no antihypertensive medication use, and freedom from reintervention. Regression analysis was performed to identify factors that would predict the need for reintervention and long-term success. RESULTS: At a median of 6 years of follow-up, long-term success was achieved in 63% (56 of 89) of patients, and 94% (96 of 102) were free of reintervention. Bivariate analysis showed that patients requiring reintervention had smaller absolute isthmus dimension (p = 0.04). No significant predictors for reintervention or long-term success could be identified, although a larger distal transverse arch dimension may play a role in long-term success (hazard ratio, 0.7; 95% confidence interval, 0.05 to 1.0; p = 0.06). CONCLUSIONS: Aortic arches of various dimensions were successfully repaired by lateral thoracotomy. No significant predictors for reintervention or long-term success could be identified, although the distal transverse arch dimension may play a role in long-term success.

Factors Influencing Pediatric Outpatient Transthoracic Echocardiography Utilization Before Appropriate Use Criteria Release: A Multicenter Study.

BACKGROUND: Although pediatric appropriate use criteria (AUC) for outpatient transthoracic echocardiography (TTE) are available, little is known about TTE utilization patterns before their release. The aims of this study were to determine the relation between AUC and TTE utilization and to identify patient and physician factors associated with discordance between the AUC and clinical practice. METHODS: A retrospective review of 3,000 initial outpatient pediatric cardiology encounters at six centers was performed. Investigator-determined indications were classified using AUC definitions. Concordance between AUC and TTE utilization was determined. Multivariate analysis was performed to identify patient and physician factors associated with TTE's being performed for rarely appropriate and TTE's not being performed for appropriate indications. RESULTS: Concordance between AUC and TTE utilization was 88%. TTE was performed for rarely appropriate indications in 9% and was associated with patient age < 3 months, indications of murmur, noninvasive imaging physician subspecialty, and physician volume. No TTE was ordered for appropriate indications in 3% and was associated with indications including prior test result (primarily abnormal electrocardiographic findings), older patients, and physician subspecialty other than generalist or imaging. There was high variability in TTE utilization among centers. CONCLUSIONS: There was a reasonable degree of concordance between AUC and clinical practice before AUC publication. Several patient and physician factors were associated with discordance with the AUC. These findings should be considered in efforts to disseminate the AUC and in the development of future iterations. The causes for variation among centers deserve further exploration.

Impaired cerebral autoregulation in preoperative newborn infants with congenital heart disease.

OBJECTIVES: To characterize cerebral autoregulation (CA) in preoperative newborn infants with congenital heart disease (CHD). METHODS: This was a prospective, pilot study of term newborns with CHD who required intensive care. Continuous mean arterial blood pressure (MAP), cerebral tissue oxygen saturation (SCTO2) via near-infrared spectroscopy, and arterial oxygen saturation (SaO2) were collected. Significant low-frequency coherence between MAP and SCTO2 was used to define impaired CA in 20-minute epochs. Cerebral fractional tissue oxygen extraction (FTOE) = (SaO2 - SCTO2)/SaO2 was calculated. Spearman's and rank bi-serial correlations and logistic linear models accounting for multiple measures were used to identify associations with impaired CA and coherence. RESULTS: Twenty-four term neonates were evaluated for 23.4 ± 1.8 hours starting the first day of life. Periods of SaO2 variability >5% were excluded, leaving 63 ± 10 epochs per subject, 1515 total for analysis. All subjects demonstrated periods of abnormal CA, mean 15.3% ± 12.8% of time studied. Significant associations with impaired CA per epoch included greater FTOE (P = .02) and lack of sedation (P = .02), and associations with coherence included greater FTOE (P = .03), lack of sedation (P = .03), lower MAP (P = .006), and lower hemoglobin (P = .02). CONCLUSIONS: Term newborns with CHD display time-varying CA abnormalities. Associations seen between abnormal CA and greater FTOE, lack of sedation, and lower hemoglobin suggest that impaired oxygen delivery and increased cerebral metabolic demand may overwhelm autoregulatory capacity in these infants. Further studies are needed to determine the significance of impaired CA in this population.

Utility of Echocardiography in the Assessment of Left Ventricular Diastolic Function and Restrictive Physiology in Children and Young Adults with Restrictive Cardiomyopathy: A Comparative Echocardiography-Catheterization Study.

The aim of the study is to determine the utility of echocardiography in the assessment of diastolic function in children and young adults with restrictive cardiomyopathy (RCM). RCM is a rare disease with high mortality requiring frequent surveillance. Accurate, noninvasive echocardiographic measures of diastolic function may reduce the need for invasive catheterization. Single-center, prospective, observational study of pediatric and young adult RCM patients undergoing assessment of diastolic parameters by simultaneous transthoracic echocardiogram (TTE) and invasive catheterization. Twenty-one studies in 15 subjects [median (IQR) = 13.8 years (7.0-19.2), 60% female] were acquired with median left ventricular end-diastolic pressure (LVEDP) 21 (IQR 18-25) mmHg. TTE parameters of diastolic function, including pulmonary vein A wave duration (r s  = 0.79) and indexed left atrial volume (r s  = 0.49), demonstrated significant positive correlation, while mitral valve A (r s  = -0.44), lateral e' (r s  = -0.61) and lateral a' (r s  = -0.61) velocities showed significant negative correlation with LVEDP. Lateral a' velocity (≤0.042 m/s) and pulmonary vein A wave duration (≥156 m/s) both had sensitivity and specificity ≥80% for LVEDP ≥ 20 mmHg. In pediatric and young adult patients with RCM, lateral a' velocity and pulmonary vein A wave duration predicted elevated LVEDP with high sensitivity and specificity; however, due to technical limitations the latter was reliably measured in 12/21 patients. These noninvasive parameters may have utility in identifying patients that require further assessment with invasive testing. These findings require validation in a multicenter prospective cohort prior to widespread clinical implementation.

Evaluation and Management of Fetal Cardiac Function and Heart Failure.

OPINION STATEMENT: Two-dimensional (2D) and Doppler echocardiography has become both an essential component in the assessment of anatomic anomalies of the fetal heart and an important tool in the assessment of fetal cardiac function. Various techniques for assessing fetal cardiovascular function exist and can be used to characterize systolic and diastolic ventricular function and estimate fetal cardiac output. These techniques can be utilized to assess fetuses with cardiovascular compromise due to a number of cardiac and non-cardiac conditions, including twin-twin transfusion syndrome, high-cardiac output lesions such as fetal tumors and vascular malformations, and primary fetal cardiomyopathy. As many of these conditions can now be treated by a variety of fetal therapeutic techniques, it is now important to be able to understand and identify fetal cardiac dysfunction. Characterization of fetal cardiac dysfunction now has the potential to provide clinicians with the means to better select patients for intervention, predict outcome, and perform follow-up following fetal interventional procedures.

Using Improvement Methodology to Optimize Echocardiographic Imaging of Coronary Arteries in Children.

BACKGROUND: According to the American Society of Echocardiography, coronary artery (CA) imaging is recommended in pediatric examinations to identify CA anomalies. A review of the authors' center's echocardiographic studies revealed that CA images were often nondiagnostic. The aim of this study was to utilize quality improvement methodology to increase the percentage of first-time pediatric studies with definitive CA identification from a baseline of 45% to a goal of at least 75% in 9 months. METHODS: A scoring system was developed to characterize the completeness of CA imaging. One point was scored for demonstration of each of the following: right CA origin by two-dimensional imaging, right CA origin by color flow Doppler imaging, left CA origin by two-dimensional imaging, and left CA origin by color flow Doppler imaging. A score of 4 was considered to represent definitive imaging. A baseline was obtained on 100 first-time echocardiograms with normal findings. During the intervention, 10 randomly selected first-time studies with normal findings were scored weekly for assessment of CA imaging. Interventions were focused on the following domains: excellence in image quality, shared ownership, transparency, and effective communication. Key interventions included labeling CA images, requiring two-dimensional and color Doppler images, optimization of settings, and elimination of macros for CA reporting. RESULTS: The percentage of definitive CA identification increased from 45% to 82.5% over 4 months and was sustained for 7 months. Accurate reporting of incomplete CA imaging increased from 17% to 77.5%. CONCLUSIONS: Improved pediatric CA imaging and reporting were achieved through the implementation of key interventions.

Intrauterine fetal demise after prenatal diagnosis of congenital heart disease: assessment of risk.

OBJECTIVES: Elective deliveries in fetal congenital heart disease (CHD) attempt to balance fetal and neonatal risk with the goal of optimizing overall outcome. However, the magnitude of the risk for intrauterine fetal demise (IUFD) is unclear. This study aimed to (1) determine the rate of IUFD and (2) identify fetal risk factors associated with IUFD. METHODS: Retrospective review of pregnancies complicated by CHD between 1998 and 2010. Data were collected regarding pregnancy outcome, extracardiac anomalies (ECA), genetic and cardiac diagnoses, severity of valve regurgitation, gestational age at birth and birth weight. Fisher's exact test and odds ratios were used to compare outcomes between groups. RESULTS: A total of 501 pregnancies analyzed resulted in 445 live births, 22 IUFD, 16 terminations and 18 unknown outcomes. Amongst IUFD, 27% had a genetic diagnosis, 50% had an ECA and 27% had severe valve regurgitation. IUFD odds increased threefold with ECA and sevenfold with severe valve regurgitation. IUFD occurred in 1.2% without risk factors. CONCLUSIONS: IUFD in fetuses with CHD is associated with ECA, genetic syndromes and severe valve regurgitation. In absence of these fetal characteristics, the occurrence of IUFD is low, although it remains higher than in fetuses without CHD.

Changes in Ventricular Geometry Predict Severity of Right Ventricular Hypertension.

Changes in ventricular geometry are often seen in patients with right ventricular hypertension secondary to pulmonary hypertension (PH). Progressive systolic bowing of the inter-ventricular septum occurs with increasing right ventricular pressure (RVp) and can be quantified with the left ventricular end-systolic eccentricity index (LVEI). Only limited data exist in children to evaluate the relationship between the LVEI and invasive RVp. We sought to assess the correlation between the LVEI and an invasively measured peak systolic RVp to aortic pressure (pAo) ratio. Medical records of patients undergoing echocardiography within 30 days of right and left heart catheterization for evaluation of PH between February 2009 and March 2014 were retrospectively reviewed. Forty-six studies in 29 subjects (median age 3.8 years, 46 % female), with a median time from echocardiogram to catheterization of -1.0 days, were included for analysis. The mean LVEI was 1.6 ± 0.5, and mean RVp/pAo ratio was 0.68 ± 0.26. There was a significant positive correlation (r = 0.76, p < 0.001) between LVEI and RVp/pAo ratio. ROC analysis demonstrated an area under the curve = 0.91 for prediction of RVp/pAo >0.50 by the LVEI. An LVEI >1.48 had a sensitivity of 76 % and specificity of 100 % in predicting RVp/pAo >0.50, while an LVEI >1.24 had a sensitivity of 88 % and specificity of 83 %. Echocardiographically derived LVEI is strongly correlated with invasively determined RVp/pAo ratio. In combination with other noninvasive measures of RVp, LVEI may help minimize the need for invasive patient evaluation.