Importance:Bronchopulmonary dysplasia (BPD) and pulmonary hypertension (PH) are leading causes of morbidity and mortality in premature infants. Objective:To determine whether images obtained as part of retinopathy of prematurity (ROP) screening might contain features associated with BPD and PH in infants and whether a multimodal model integrating imaging features with demographic risk factors might outperform a model based on demographic risk alone. Design, Setting, and Participants:A deep learning model was used to study retinal images collected from patients enrolled in the multi-institutional Imaging and Informatics in Retinopathy of Prematurity (i-ROP) study. The analysis included infants at risk for ROP undergoing routine ROP screening examinations from 2012 to 2020. Infants were recruited from 7 neonatal intensive care units. Images were limited to 34 weeks' or less postmenstrual age (PMA) so as to precede the clinical diagnosis of BPD or PH. The dataset included the period from June 2015 to April 2020. Data were analyzed from April to June 2025. Exposures:BPD was diagnosed by the presence of an oxygen requirement at 36 weeks' PMA, and PH was diagnosed by echocardiogram at 34 weeks. A support vector machine model was trained to predict BPD or PH diagnosis using (1) image features alone (extracted using ResNet18), (2) demographics alone, or (3) image features concatenated with demographics. To reduce the possibility of confounding with ROP, secondary models were trained using only images without clinical signs of ROP. Main Outcomes and Measures:For both BPD and PH, performance was reported on a held-out test set and assessed by the area under receiver operating characteristic curve (AUROC). Results:A total of 493 infants (mean [SD] gestational age, BPD, 25.7 [1.8] weeks; normal, 27.3 [1.8] weeks; 267 male [54.2%]) were included in this analysis. Performance was reported on a held-out test set (99 patients from the BPD cohort and 37 patients from the PH cohort). For BPD, the multimodal model showed higher accuracy (AUC, 0.82; 95% CI, 0.72-0.90) than demographics-only (0.72; ∆AUC, 0.1; 95% CI, -0.008 to 0.21; P = .07) or imaging-only (0.72; ∆AUC, 0.1; 95% CI, 0.04-0.16; P = .002) models. For PH, multimodal AUC was 0.91 vs the demographics-only 0.68 (∆AUC, 0.14; 95% CI, 0.006-0.27; P = .04) and imaging-only 0.91 (∆AUC, -0.09; 95% CI, -0.3 to 0.12; P = .40) models. Results persisted when trained on images lacking clinical ROP signs. Conclusions and Relevance:Results suggest that retinal images obtained during ROP screening may be used to predict the diagnosis of BPD and PH in preterm infants, which may lead to earlier diagnosis and avoid the need for invasive diagnostic testing in the future.

OBJECTIVE:To quantify the impact of nonhemodynamically significant patent ductus arteriosus (non-hsPDA) on pulmonary function in neonates. STUDY DESIGN:We analyzed a retrospective cohort of very low birthweight (<1500 g) infants born <32 weeks' gestation admitted to a single tertiary neonatal intensive care unit between 2019 and 2023 who underwent both echocardiography and pulmonary function testing at approximately 34 weeks postmenstrual age. Infants with ventricular or atrial septal defects were excluded. Passive respiratory compliance (Crs) was compared among infants with hsPDA, non-hsPDA, and age-matched controls without PDA using one-sided t-tests and ANOVA, with multivariable regression controlling for birth weight and length. RESULTS:Twenty-four infants were analyzed (8 hsPDA, 8 non-hsPDA, 8 controls). Mean Crs was significantly reduced in both hsPDA (0.83 ± 0.34 mL/cmH2O/kg) and non-hsPDA (0.92 ± 0.21) groups compared with controls (1.23 ± 0.34; P < .05). The presence of PDA demonstrated a stepwise inverse relationship with Crs that persisted after adjustment for covariates. CONCLUSIONS:Even non-hsPDAs are associated with measurable reductions in pulmonary compliance among preterm infants. These findings suggest that current binary classifications of PDA significance may underestimate pulmonary impact and support re-evaluation of management thresholds for "non-significant" shunts.

BACKGROUND:Maternal hypertension has a complex and not fully understood impact on the fetal heart. OBJECTIVE:The study investigated the impact of various forms of maternal hypertension on fetal heart function and ventricular remodeling and follows up postnatal outcomes. METHODS:The research involved 45 pregnant women with hypertension and 15 with normal pregnancies. Fetal echocardiograms were conducted between 24 and 34 weeks of pregnancy using various methods to evaluate cardiac function. The study measured ventricular transverse and longitudinal diameters, along with the sphericity index. Follow-up postnatal echocardiograms were also conducted. RESULTS:The study included 15 cases each of gestational hypertension, chronic hypertension, and preeclampsia, with 15 control subjects. The E/A ratio of the tricuspid valve was significantly lower in fetuses in all groups compared to the control group. The E wave was significantly reduced in the chronic hypertension and preeclampsia groups (p < 0.001) compared to the control group. The Tei Doppler index for the left and right ventricles was significantly higher in both chronic hypertension and preeclampsia groups, affecting both fetuses and neonates. However, there was no statistically significant difference in gestational hypertension for either fetuses or neonates. In fetuses, the left ventricle had a decreased transverse dimension in both the chronic hypertension and preeclampsia groups (p < 0.001 and 0.002). In neonates, the transverse diameter decreased significantly in all groups (p < 0.037, 0.005, and 0.012 respectively). The right ventricle showed a significant increase in transverse diameter in the chronic hypertension and preeclampsia groups in fetuses and only in the chronic group in neonates. The E' wave was also significantly different in both the preeclampsia and chronic hypertension groups. The E/ E' of the left ventricle in preeclampsia was statistically significant in both fetuses and neonates. CONCLUSION:Hypertensive pregnancies can affect fetal cardiac function and structure, which may persist into the early days of life.

BACKGROUND:Pediatric patients with heart failure/cardiomyopathy (HF/CM) require longitudinal cardiology clinic visits and are at risk for experiencing emergency room visits/hospitalizations. The purpose of this study was to examine continuity in care (COC) of cardiology visits and related outcomes of pediatric HF/CM patients prior to and after institution of a HF/CM nurse-coordinator. COC was measured as a HF/CM office visit within three months of the date that the patient was due for follow-up care. METHODS:We examined differences in COC between patients in the program compared with COC in the preceding pediatric cardiology care model. We also compared HF/CM-related emergency room visits/hospitalizations. RESULTS:A total of 98 patients were enrolled in the pediatric HF/CM program. Of the 98 patients, 38 received preceding cardiology care at our institution. Of these 38 patients, once in the program they had significantly higher COC (log-rank 3.95, p = 0.046) and significantly fewer emergency room visits/hospitalizations than those under previous pediatric cardiology care model (U = 65, p = 0.001). The rank-biserial correlation coefficient was 0.28, indicating a medium effect size. CONCLUSIONS:There were significant increases in COC and significant decreases in HF/CM emergency room visits/hospitalizations after institution of a pediatric HF/CM nurse coordinator.

The impact of maternal diabetes on the fetal heart is complex and not fully understood. The study aimed to investigate how different types and stages of maternal diabetes affect fetal heart function and ventricular remodeling during prenatal and postnatal periods. The study included 45 pregnant women with diabetes and 15 with uncomplicated pregnancies. Fetal echocardiograms were performed between 28 and 32 weeks of gestation using different techniques to assess cardiac function. Measurements of ventricular transverse and longitudinal diameters, as well as the sphericity index, were determined. Postnatal follow-up echocardiograms were also performed. The diabetic pregnant group was divided into three subgroups: 15 with GDM and 30 with PGD, including 15 wellcontrolled and 15 uncontrolled cases. The E and E/A ratio values for the mitral and tricuspid valves were significantly lower in fetuses and neonates affected by diabetes compared to the healthy group. The Tei-Doppler index for the left ventricle was significantly higher in pregnancies affected by diabetes, affecting both fetuses and neonates. The right ventricle exhibited significant differences in all groups of diabetic pregnancies in fetuses and postnatally in cases of pregestational diabetes. The sphericity index differed significantly in all fetal diabetic groups and in neonates compared to controls, except for the LV in the GDM cohort. Postnatally, the sphericity index of the RV increased compared to fetal values, while the LV sphericity index remained unchanged. Maternal diabetes mellitus affects fetal cardiac function and structure, which may continue into the early days of life.

BACKGROUND:International organisations recommend that patients with CHD undergo a structured transition process to prepare for lifelong cardiac care. However, there is a limited understanding of current transition practices in the United States (U.S.) from the perspective of adult CHD programs. The purpose of this study was to characterise adult CHD transition practices across the U.S. METHOD:We conducted a descriptive, cross-sectional survey of adult CHD programs in the U.S., inquiring about transition practices (preparation, transfer, and integration), resources, specialists, and barriers. We used descriptive statistics to analyse the data. RESULTS:We analysed responses from 38 adult CHD programs (37% response rate). Among these, 25 (66%) of adult CHD programs reported formal transition programs and 26 (68%) reported having a transfer process to receive patients from paediatric cardiology. Reported transition program specialists were interdisciplinary. Few programs reported having psychologists or psychiatrists on their teams or offered support for patients with intellectual disability. The main barriers affecting transition were insurance and health care costs. CONCLUSION:Around two-thirds of respondent adult CHD programs reported the presence of formal transition programs. More resources may be needed within these programmes to support patient psychological well-being and those with intellectual disability and to address barriers related to insurance and health care costs.

Background American Indians face significant barriers to diagnosis and management of cardiovascular disease. We sought to develop a real‐world implementation model for improving access to echocardiography within the Indian Health Service, the American Indian Structural Heart Disease Partnership. Methods and Results The American Indian Structural Heart Disease Partnership was implemented and evaluated via a 4‐step process of characterizing the system where it would be instituted, building point‐of‐care echocardiography capacity, deploying active case finding for structural heart disease, and evaluating the approach from the perspective of the clinician and patient. Data were collected and analyzed using a parallel convergent mixed methods approach. Twelve health care providers successfully completed training in point‐of‐care echocardiography. While there was perceived usefulness of echocardiography, providers found it difficult to integrate screening point‐of‐care echocardiography into their workday given competing demands. By the end of 12 months, 6 providers continued to actively utilize point‐of‐care echocardiography. Patients who participated in the study felt it was an acceptable and effective approach. They also identified access to transportation as a notable challenge to accessing echocardiograms. Over the 12‐month period, a total of 639 patients were screened, of which 36 (5.6%) had a new clinically significant abnormal finding. Conclusions The American Indian Structural Heart Disease Partnership model exhibited several promising strategies to improve access to screening echocardiography for American Indian populations. However, competing priorities for Indian Health Service providers' time limited the amount of integration of screening echocardiography into outpatient practice. Future endeavors should explore community‐based solutions to develop a more sustainable model with greater impact on case detection, disease management, and improved outcomes.

BACKGROUND:Very low birth weight (VLBW) infants demonstrate altered alveolar and pulmonary vascular development and carry an increased risk of developing bronchopulmonary dysplasia (BPD) and pulmonary hypertension (PH). Risk stratification for BPD-associated PH (BPD-PH) in at-risk infants may help tailor management, improve outcomes, and optimize resource utilization. METHODS:VLBW infants were screened for PH with blood gas measurements, serum NT-proBNP and bicarbonate (HCO3) levels, and echocardiograms if they remained on respiratory support at 34 weeks corrected gestational age. We then tested 11 models using different cutoffs for NT-proBNP and HCO3 to predict infants at low risk of BPD-PH. RESULTS:We identified PH in 34 of 192 (17.6%) VLBW infants. The median NT-proBNP in VLBWs with PH was 2769 pg/mL versus 917 pg/mL in those without PH (p < 0.0001). A model with NT-proBNP < 950 pg/mL and HCO3 < 32 mmol/L had a sensitivity of 100%, specificity of 34.2%, and negative predictive value of 100%. Using this model, 54 of 192 (28%) of the patients in this study would have been categorized as low risk for PH and could have avoided a screening echocardiogram. CONCLUSION:NT-proBNP and HCO3 together may serve as sensitive and cost-effective screening tools for BPD-PH in VLBW infants. IMPACT:NT-proBNP and HCO3 concentrations obtained together may help identify very low birth weight infants at risk for bronchopulmonary dysplasia who should undergo screening for pulmonary hypertension with echocardiography. This large dataset demonstrates that NT-proBNP and HCO3 levels together are more sensitive than NT-proBNP alone in identifying VLBW infants to undergo echocardiography. The combination of NT-proBNP and HCO3 levels may identify VLBW infants at low risk for pulmonary hypertension and thus those who may be able to avoid screening echocardiography.

Sinus node dysfunction (SND) with junctional rhythm (JR) is common after the Fontan operation. Atrial pacing (AP) restores atrioventricular (AV) synchrony, but the placement of a pacemaker carries significant morbidity. To study the impact of AP on echocardiographic parameters of function in Fontan patients with SND and JR. Nine Fontan patients with AP for SND and JR were prospectively studied with echocardiography in the following conditions—baseline paced rhythm, underlying JR and, if possible, slow-paced rhythm below their baseline paced rate (~ 10 bpm faster than their JR rate). Cardiac index was significantly lower in JR (3 ± 1.1 L/min/m 2 ) vs AP (4.2 ± 1.4 L/min/m 2 ; p = 0.002). Diastolic function also significantly worsened with increased ratio of early diastolic systemic AV valve inflow velocity to early diastolic systemic AV valve annulus velocity (E/e ′ ratio) by tissue Doppler imaging (TDI) in JR (11.6 ± 4.6) vs AP (8.8 ± 2.2, p = 0.016). Pulmonary venous flow reversal was present in 7/9 patients in JR vs 0/9 in AP ( p = 0.016). There were no significant differences in these echocardiographic measurements between the paced and slow-paced conditions. When compared to AP, JR was associated with a significant reduction in cardiac output and diastolic function, and an increased prevalence of pulmonary vein flow reversal. There were no differences between paced and slow-paced conditions, suggesting that AV synchrony rather than heart rate was primarily contributing to cardiac output. Further studies are needed to understand the chronic impact of JR on Fontan outcomes.

•Conducting transition program activities in pediatric cardiology clinics can be a challenge if there are limited resources.•We tested a Medical Assistant-facilitated transition activity in this setting.•The activity increased documentation of transition discussions.•Staff were accepting and in favor of continuing this activity.

AbstractParenteral prostanoid therapy (PPT) can result in supranormal cardiac index (SCI; >4 L/min/m2) in pediatric pulmonary hypertension (PPH) patients. We evaluated the incidence, hemodynamic factors, and outcomes associated with SCI in PPH. This retrospective cohort study included 22 PPH patients on PPT from 2005 to 2020. Hemodynamic profiles were compared between the baseline and 3–6 month follow‐up catheterization in the SCI and non‐SCI cohorts. Cox regression analysis examined time to composite adverse outcome (CAO; Potts shunt, lung transplant, or death) controlling for initial disease severity. SCI developed in 17 (77%) patients, of whom 11 (65%) developed SCI within 6 months. The SCI cohort was characterized by significant augmentation of cardiac index (CI) and stroke volume (SV) as well as reductions in systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR). Conversely, the non‐SCI cohort had unchanged SV despite a modest rise in CI as well as persistent vasoconstriction. After median follow‐up of 4.3 years (range 0.2–13 years), non‐SCI patients were at significantly increased risk for the CAO (5/5: three deaths, two Potts shunts) compared with SCI patients (5/17: two deaths, three lung transplants; adjusted hazard ratio 14.0 [95% confidence interval: 2.1–91.3], p < 0.001). A majority of PPH patients developed SCI within 6–12 months of starting PPT and demonstrated lower risk of adverse outcomes compared with non‐SCI patients. These data suggest that change in SVR and SV after 3–6 months of PPT may be early markers of therapeutic response and prognosis.

OBJECTIVES: Postoperative patients after congenital cardiac surgery are at high risk of fluid overload (FO), which is known to be associated with poor outcomes. "Fluid creep," or nonresuscitation IV fluid in excess of maintenance requirement, is recognized as a modifiable factor associated with FO in the general PICU population, but has not been studied in congenital cardiac surgery patients. Our objective was to characterize fluid administration after congenital cardiac surgery, quantify fluid creep, and the association between fluid creep, FO, and outcome.DESIGN: Retrospective, observational cohort study.SETTING: Single-center urban mixed-medical and cardiac PICU.PATIENTS: Patients admitted to the PICU after cardiac surgery between January 2010 and December 2020.INTERVENTIONS: None.MEASUREMENTS AND MAIN RESULTS: There were 1,459 postoperative encounters with 1,224 unique patients. Total fluid intake was greater than maintenance requirements on 3,103 of 4,661 patient days (67%), with fluid creep present on 2,624 patient days (56%). Total nonresuscitation intake was higher in patients with FO (defined as cumulative fluid balance 10% above body weight) versus those without. Fluid creep was higher among patients with FO than those without for each of the first 5 days postoperatively. Each 10 mL/kg of fluid creep in the first 24 hours postoperatively was associated with 26% greater odds of developing FO (odds ratio [OR] 1.26; 95% CI, 1.17-1.35) and 17% greater odds of mortality (OR 1.17; 95% CI, 1.05-1.30) after adjusting for risk of mortality based on surgical procedure, age, and day 1 resuscitation volume. Increasing fluid creep in the first 24 hours postoperatively was associated with increased postoperative duration of mechanical ventilation and PICU length of stay.CONCLUSIONS: Fluid creep is present on most postoperative days for pediatric congenital cardiac surgery patients, and fluid creep is associated with higher-risk procedures. Fluid creep early in the postoperative PICU stay is associated with greater odds of FO, mortality, length of mechanical ventilation, and PICU length of stay. Fluid creep may be under-recognized in this population and thus present a modifiable target for intervention.

Sinus node dysfunction with concomitant junctional rhythm (JR) is frequently observed among Fontan patients and has been recognized as a contributor to heart failure. The impact and management of JR is unclear. A survey was mailed to all members of the Pediatric and Congenital Electrophysiology society (PACES) and members were asked to forward the questionnaire to their non-electrophysiology colleagues. Responses were received from 154 physicians (88 electrophysiologists (EP’s) and 66 non-EP’s (46 pediatric cardiologists and 20 adult congenital cardiologists). There were few differences in the response between EP’s and non-EP’s. Overall, 57% recommended an annual ambulatory ECG (AECG). A significant majority (80%) opted to continue to follow patients with significant periods of JR on AECG as long as the patients were asymptomatic, and showed no echocardiographic signs of cardiac decompensation. However, 84% would place a pacemaker in a patient with JR who was having open chest surgery for other reasons. Finally, pacemaker placement would be performed by 91% if a patient with JR showed signs of heart failure. Most congenital cardiologists would not recommend pacemaker placement in asymptomatic Fontan patients with JR. Further studies are needed on the Fontan population to determine the impact of SND and JR on longer term outcomes and to determine the role and optimal timing of pacemaker placement in these patients.

BACKGROUND:The high complexity of mitral valve anatomy and function in mitral valve prolapse (MVP) is not yet fully understood.OBJECTIVE:The purpose of this study was to analyze each part of the mitral valve apparatus in children to determine its impact on the presence of MVP and to assess the interaction between the coaptation length (CL) and mitral regurgitation severity.METHODS:We prospectively analyzed transthoracic echocardiograms of 60 patients with MVP (mean age 9.8 ± 3.1 years). We compared these patients with 60 control patients without disease. We determined length of leaflets, chordal length, tenting area, coaptation CL, the intrapapillary muscle distance (IPMD) and relation between CL and severity of mitral regurgitation (MR).RESULTS:For patients with MVP, the posterior mitral leaflet (PML) was significantly enlarged 13.9 ± 4.1 mm versus 10.7 ± 3.5 mm (p < .01), the primary chordal length was significantly decreased 15.4 ± 3.61 mm versus 17.6 ± 3.8 mm (p < .02), and IPMD was significantly greater 18.1 ± 2.7 mm versus 16.6 ± 4.3 mm (p < .03). The difference between CL for both the anterior and posterior mitral leaflets correlated positively with MR (r = .249, p < .05). A greater than 4 mm CL correlated with at least MR (sensitivity 100%, specificity 72%) and greater than 5 mm correlated with at least moderate MR (sensitivity 100%, specificity 60%).CONCLUSION:The majority of pediatric patients with mitral valve prolapse have structural abnormalities that are defined well by echocardiography. In addition to the presence of prolapse and regurgitation, routine assessment of leaflet length, thickness, chordal length and papillary muscle distance is fundamental for patients with MVP.

Background:Supraventricular tachycardia (SVT) is a common arrhythmia. Infants with SVT are often admitted to initiate antiarrhythmics. Transesophageal pacing (TEP) studies can be used to guide therapy prior to discharge. Objective:The objective of this study was to investigate the impact of TEP studies on length of stay (LOS), readmission, and cost in infants with SVT. Methods:This was a 2-site retrospective review of infants with SVT. One site (Center TEPS) utilized TEP studies in all patients. The other (Center NOTEP) did not. Patients with structural heart disease, patients with gestational age <34 weeks, and patients diagnosed after 6 months were excluded. At Center TEPS, repeat TEP studies were performed after titration of medication until SVT was not inducible. Primary endpoints were LOS and readmission for breakthrough SVT within 31 days of discharge. Hospital reimbursement data were utilized for cost-effectiveness analysis. Results:The cohort included 131 patients, 59 in Center TEPS and 72 in Center NOTEP. One patient was readmitted in Center TEPS vs 17 in Center NOTEP (1.6% vs 23.6%; P ≤ .001). Median LOS was longer for Center TEPS at 118.0 (interquartile range [IQR] 74.0-189.5) hours vs Center NOTEP at 66.9 (IQR 45.5-118.3) hours (P = .001). Twenty-one patients had multiple TEP studies. Median length of readmission for Center NOTEP was 65 (IQR 41-101) hours. Including readmission costs, utilization of TEP studies resulted in a probability-weighted cost of $45,531 per patient compared with $31,087 per patient without TEP studies. Conclusion:Utilization of TEP studies was associated with decreased readmission rates but longer LOS and greater cost compared with SVT management without TEP studies.

Pediatric patients with moderate and great complexity congenital heart disease (CHD) may benefit from coordinated transfer to adult congenital heart disease (ACHD) centers to reduce the risk of complications; however, there are a variety of transfer practices. We examined the impact of referral order placement at the last pediatric cardiology visit on time to transfer to an ACHD center. We analyzed data collected from pediatric patients with moderate and great complexity CHD who were eligible to transfer to our tertiary center's accredited ACHD center. We examined transfer outcomes and time-to-transfer between those with a referral order placed at the last pediatric cardiology visit and those without using Cox proportional hazards modeling. The sample (n = 65) was 44.6% female and mean age at study start was 19.5 years (± 2.2). Referral orders were placed for 32.3% of patients at the last pediatric cardiology visit. Those who had a referral order placed at the last visit had significantly higher number of successful transfers to the ACHD center compared to those who did not (95% vs 25%, p < 0.001). In a Cox regression model, placement of a referral order at the last pediatric cardiology visit was associated significantly with a sooner time to transfer (HR 6.0; 95% CI 2.2-16.2, p > 0.001), adjusting for age, sex, complexity, living location, and pediatric cardiology visit location. Placement of a referral order at the last pediatric cardiology visit may improve transfer occurrence and time to transfer to accredited ACHD centers.

Objective To evaluate the cost-utility of catheterization-obligate treatment in preterm infants with pulmonary hypertension, as compared with empiric initiation of sildenafil based on echocardiographic findings alone. Study design A Markov state transition model was constructed to simulate the clinical scenario of a preterm infant with echocardiographic evidence of pulmonary hypertension associated with bronchopulmonary dysplasia (BPD) and without congenital heart disease under consideration for the initiation of pulmonary vasodilator therapy via one of two modeled treatment strategies-empiric or catheterization-obligate. Transitional probabilities, costs and utilities were extracted from the literature. Forecast quality-adjusted life-years was the metric for strategy effectiveness. Sensitivity analyses for each variable were performed. A 1000-patient Monte Carlo microsimulation was used to test the durability of our findings. Results The catheterization-obligate strategy resulted in an increased cost of $10 778 and 0.02 fewer quality-adjusted life-years compared with the empiric treatment strategy. Empiric treatment remained the more cost-effective paradigm across all scenarios modeled through one-way sensitivity analyses and the Monte Carlo microsimulation (cost-effective in 98% of cases). Conclusions Empiric treatment with sildenafil in infants with pulmonary hypertension associated with BPD is a superior strategy with both decreased costs and increased effectiveness when compared with catheterization-obligate treatment. These findings suggest that foregoing catheterization before the initiation of sildenafil is a reasonable strategy in preterm infants with uncomplicated pulmonary hypertension associated with BPD.

Upon diagnosis of pulmonary hypertension in pediatrics, standard practice often involves acute vasoreactivity testing (AVT) in the cardiac catheterization laboratory. However, the importance of repeated AVT testing in a given patient thereafter remains unclear. This study sought to describe serial AVT results in pediatric patients and understand the prognostic significance of longitudinal AVT results in pediatric pulmonary hypertension. A retrospective chart review was performed for pediatric pulmonary hypertension patients diagnosed between 2008 and 2021. Patients were included if they had two or more catheterizations with AVT. The study cohorts were patients who were AVT negative upon initial catheterization then AVT positive at any subsequent catheterization (AVT-/+) compared to those were AVT negative upon initial and all subsequent catheterizations (AVT-/-). A positive AVT was defined by Sitbon criteria. The analyzed outcome was event-free survival. The relationship between study cohorts and event-free survival was analyzed by log-rank Kaplan-Meier survival as well as Cox proportional hazard regression to control for confounders. There were 35 patients who met inclusion criteria in this time period. Patients who were AVT(-/+) had statistically significantly better event-free survival than AVT(-/-) (p = 0.002). In univariate and multivariate Cox regressions, a subsequent AVT positive result amongst those who were initially AVT negative was a positive prognostic factor, hazard ratio 0.03 (95% confidence interval: 0.02-0.35). For patients with negative AVT upon initial cardiac catheterization, this data supports that continuing AVT should be performed as any subsequent AVT positive result may indicate improved expectations for event-free survival.

Pulmonary hypertension (PHTN) is a common pathology in pediatrics, arising from a diverse array of etiologies and manifesting in equally diverse patient populations. The inpatient management of these infants and children may be complicated by dynamic and at times severe increases in pulmonary vascular resistance (PVR) and right ventricular (RV) afterload. Yet absent are cognitively accessible heuristics in the field whereby providers can reconcile the various clinical manifestations they observe with an understanding of the cardiac physiology at play, and therefore, appropriate physiology-driven interventions. Described herein is a framework for understanding the pathophysiology of four clinical phenotypes which are driven by two echocardiographic patient characteristics: the presence or absence of an atrial communication and the capacity of the right ventricle to maintain ventricular-vascular coupling. Application of this paradigm may facilitate accurate interpretation of observed clinical data, and alignment of treatment strategies with the underlying pathophysiology.