Early Left Ventricular Dysfunction and Severe Pulmonary Hypertension Predict Adverse Outcomes in "Low-Risk" Congenital Diaphragmatic Hernia

"Heart of the Matter": Cardiac Dysfunction in Congenital Diaphragmatic Hernia

Despite advances in caring for neonates with congenital diaphragmatic hernia (CDH), mortality and morbidity continues to be high. Additionally, the pathophysiology of cardiac dysfunction in this condition is poorly understood. Postnatal cardiac dysfunction in neonates with CDH may be multifactorial with origins in fetal life. Mechanical obstruction, competition from herniated abdominal organs into thoracic cavity combined with redirection of ductus venosus flow away from patent foramen ovale leading to smaller left-sided structures may be a contributing factor. This shunting decreases left atrial and left ventricular blood volume, which may result in altered micro- and macrovascular aberrations affecting cardiac development in the prenatal period. Direct mass effect from herniated intra-abdominal contents restricting cardiac growth and/or reduced left ventricular preload may contribute independently to left ventricular dysfunction in the absence of right ventricular dysfunction and or pulmonary hypertension. With variable clinical phenotypes of cardiac dysfunction, pulmonary hypertension, and respiratory failure in patients with CDH, there is increased need for individualized diagnosis and tailored therapy. Routine use of therapy such as inhaled nitric oxide and sildenafil that induces significant pulmonary vasodilation may be detrimental in left ventricle dysfunction, whereas in a patient with pure right ventricle dysfunction, they may be beneficial. Targeted functional echocardiography serves as a real-time tool for defining the pathophysiology and aids optimization of vasoactive therapy in affected neonates. KEY POINTS: · Cardiac dysfunction in neonates with CDH is multifactorial.. · Postnatal cardiac dysfunction in patients with CDH has its origins in fetal life.. · Right ventricular dysfunction contributes to systemic hypotension.. · Left ventricular dysfunction contributes to systemic hypotension.. · Supportive therapy should be tailored to clinical phenotype..

Long-term follow-up of patients with congenital diaphragmatic hernia

Neonates with congenital diaphragmatic hernia encounter a number of surgical and medical morbidities that persist into adulthood. As mortality improves for this population, these survivors warrant specialized follow-up for their unique disease-specific morbidities. Multidisciplinary congenital diaphragmatic hernia clinics are best positioned to address these complex long-term morbidities, provide long-term research outcomes, and help inform standardization of best practices in this cohort of patients. This review outlines long-term morbidities experienced by congenital diaphragmatic hernia survivors that can be addressed in a comprehensive follow-up clinic.

The CDH Study Group: Past, Present, and Future

The Congenital Diaphragmatic Hernia Study Group (CDHSG) is an international consortium of medical centers actively collecting and voluntarily contributing data pertaining to live born congenital diaphragmatic hernia (CDH) patients born and/or managed at their institutions. These data are aggregated to construct a comprehensive registry that participating centers can access to address specific clinical inquiries and track patient outcomes. Since its establishment in 1995, 147 centers have taken part in this initiative, including 53 centers from 17 countries outside the United States, with 95 current active centers across the globe. The registry has amassed data on over 14,000 children, resulting in the creation of over 75 manuscripts based on registry data to date. International, multicenter consortia enable health care professionals managing uncommon, complex, and diverse diseases to formulate evidence-based hypotheses and draw meaningful and generalizable conclusions for clinical inquiries. This review will explore the formation and structure of the CDHSG and its registry, outlining their functions, center participation, and the evolution of data collection. Additionally, we will provide an overview of the evidence generated by the CDHSG, with a particular emphasis on contributions post-2014, and look ahead to the future directions the study group will take in addressing CDH.

Targeted Neonatal Echocardiography in the Management of Neonatal Pulmonary Hypertension

Pulmonary hypertension (PH) in neonates, originating from a range of disease states with heterogeneous underlying pathophysiology, is associated with significant morbidity and mortality. Although the final common pathway is a state of high right ventricular afterload leading to compromised cardiac output, multiple hemodynamic phenotypes exist in acute and chronic PH, for which cardiorespiratory treatment strategies differ. Comprehensive appraisal of pulmonary pressure, pulmonary vascular resistance, cardiac function, pulmonary and systemic blood flow, and extrapulmonary shunts facilitates delivery of individualized cardiovascular therapies in affected newborns.

Unique Cardiopulmonary Interactions in Congenital Diaphragmatic Hernia: Physiology and Therapeutic Implications

Congenital diaphragmatic hernia (CDH) results in abdominal contents entering the thoracic cavity, affecting both cardiac and pulmonary development. Maldevelopment of the pulmonary vasculature occurs within both the ipsilateral lung and the contralateral lung. The resultant bilateral pulmonary hypoplasia and associated pulmonary hypertension are important components of the pathophysiology of this disease that affect outcomes. Despite prenatal referral to specialized high-volume centers, advanced ventilation strategies, pulmonary hypertension management, and the option of extracorporeal membrane oxygenation, overall CDH mortality remains between 25% and 30%. With increasing recognition that cardiac dysfunction plays a large role in morbidity and mortality in patients with CDH, it becomes imperative to understand the different clinical phenotypes, thus allowing for individual patient-directed therapies. Further research into therapeutic interventions that address the cardiopulmonary interactions in patients with CDH may lead to improved morbidity and mortality outcomes.

Prognostic value of echocardiographic parameters in congenital diaphragmatic hernia: a systematic review and meta-analysis

BACKGROUND

Prognostication of mortality and decision to offer extracorporeal membrane oxygenation (ECMO) treatment in infants with congenital diaphragmatic hernia (CDH) can inform clinical management.

OBJECTIVE

To summarise the prognostic value of echocardiography in infants with CDH.

METHODS

Electronic databases Ovid MEDLINE, Embase, Scopus, CINAHL, the Cochrane Library and conference proceedings up to July 2022 were searched. Studies evaluating the prognostic performance of echocardiographic parameters in newborn infants were included. Risk of bias and applicability were assessed using the Quality Assessment of Prognostic Studies tool. We used a random-effect model for meta-analysis to compute mean differences (MDs) for continuous outcomes and relative risk (RR) for binary outcomes with 95% CIs. Our primary outcome was mortality; secondary outcomes were need for ECMO, duration of ventilation, length of stay, and need for oxygen and/or inhaled nitric oxide.

RESULTS

Twenty-six studies were included that were of acceptable methodological quality. Increased diameters of the right and left pulmonary arteries at birth (mm), MD 0.95 (95% CI 0.45 and 1.46) and MD 0.79 (95% CI 0.58 to 0.99), respectively) were associated with survival. Left ventricular (LV) dysfunction, RR 2.40, (95% CI 1.98 to 2.91), right ventricular (RV) dysfunction, RR 1.83 (95% CI 1.29 to 2.60) and severe pulmonary hypertension (PH), RR 1.69, (95% CI 1.53 to 1.86) were associated with mortality. Left and RV dysfunctions, RR 3.30 (95% CI 2.19 to 4.98) and RR 2.16 (95% CI 1.85 to 2.52), respectively, significantly predicted decision to offer ECMO treatment. Limitations are lack of consensus on what parameter is optimal and standardisation of echo assessments.

CONCLUSIONS

LV and RV dysfunctions, PH and pulmonary artery diameter are useful prognostic factors among patients with CDH.

Recent advances in the treatment of complex congenital diaphragmatic hernia-a narrative review

Background and Objective

Congenital diaphragmatic hernia (CDH) is an anomaly of the cardiopulmonary system maturation process that results from both a global embryopathy and concomitant mechanical compression of the cardiopulmonary system from the abdominal contents during fetal maturation. This results in pulmonary hypertension, pulmonary hypoplasia, and cardiac dysfunction, requiring intense critical care management. The patients with highest risk CDH are the most challenging, resource-intensive, and bear most of the mortality. Advances at the basic, translational, and clinical research levels are leading to novel therapies and management strategies for complex, high-risk CDH. Our objective is to review novel approaches in thinking and management for the most complex and high-risk CDH patients. These include patients with prenatal and postnatal indicators of high-risk defects, those receiving extracorporeal life support (ECLS), and those with concomitant anomalies such as complex cardiac and/or chromosomal abnormalities.

Methods

PubMed was searched in late 2022 and early 2023 to identify relevant evidence. Search terms included congenital diaphragmatic hernia (CDH)", "extracorporeal life support (ECLS)", "pulmonary hypertension", "dual-hit hypothesis", "risk reduction", "cardiac/chromosomal anomalies", and "novel therapies". We included trials, multicenter studies (prospective and retrospective), single-center reports, and review articles/expert opinion.

Key Content and Findings

CDH is a congenital anomaly of the cardiopulmonary and diaphragmatic systems that represents a spectrum of disease. High-risk or complex patients are defined by prenatal/postnatal risk stratification, receipt of ECLS, and/or having concomitant anomalies, representing the severe end of that spectrum. Overall survival of high-risk CDH is about 50% and comprises the vast majority of mortality, mandating special emphasis. The development of risk-stratification processes, best practices or guidelines of management, and novel therapies is critical to optimize the care of these infants.

Conclusions

CDH patients with high-risk disease remain a challenging subset of CDH patients. Increasing opportunities for survival are being realized with novel, investigational approaches.

A potential cause of left ventricular dysfunction after surgery in neonates with low-risk congenital diaphragmatic hernia: high-tension repair

BACKGROUND

Congenital diaphragmatic hernia (CDH) is a serious congenital malformation. Given the focus on improving survival in patients with "high-risk" CDH, it is possible that risk factors for low-risk patient with CDH may not be a concern. Left heart failure leads to adverse postoperative outcomes, including the need for extracorporeal membrane oxygenation (ECMO). The purpose of this study was to explore the causes of postoperative left heart failure in the low-risk group.

METHODS

A retrospective study was conducted on newborns with congenital diaphragmatic hernia who were surgically treated in our hospital from January 2018 to March 2022. Children at low risk were divided into three groups according to the intraoperative repair conditions. Group A was defined as grade A defects repaired by direct suture. Group B was defined as a grade B defect repaired by mesh. Group C was a grade B defect repaired by high-tension suture. The age, gender, weight, perioperative echocardiography, and follow-up of the patients were statistically analyzed. The risk factors of left ventricular dysfunction after surgery in neonates with low-risk congenital diaphragmatic hernia were analyzed.

RESULTS

A total of 52 low-risk children were included in the study. For children in the low-risk group, there was no significant difference between the low-tension repair group and the high-tension repair group in terms of operation time, thoracic tube drainage time, hospital stay, and long-term survival rate. Group A and group B showed good left ventricular function, while group C showed more decreased left ventricular EF and LVFS (LVEF 54.06 ± 10.28, LVFS 26.94 ± 5.83, p < 0.001). On the comparison of measures of left ventricular size, the mean values of left ventricular end-diastolic diameters(LVDD) and left ventricular end-systolic diameters (LVDS) were significantly difference in group C. Univariate analysis showed that LHR, o/e LHR, operation time, and high-tension repair were the influencing factors of left ventricular dysfunction. Multivariate logistic regression analysis identified risk factors for high-tension repair. Severe left heart dysfunction occurred in 2 patients with ECMO requirement in the high-tension repair group, although the difference was not significant.

CONCLUSIONS

High-tension repair is a potential cause of left ventricular dysfunction in neonates with low-risk CDH.

Successful extracorporeal membrane oxygenation for postoperative cardiopulmonary failure in newborns with congenital diaphragmatic hernia: case reports and literature reviews

Introduction

Congenital diaphragmatic hernia (CDH) is a structural defect caused by inadequate fusion of the pleuroperitoneal membrane that forms the diaphragm, allowing peritoneal viscera to protrude into the pleural cavity. Up to 30% of newborns with CDH require extracorporeal membrane oxygenation (ECMO) support. As with all interventions, the risks and benefits of ECMO must be carefully considered in these patients. Cardiopulmonary function has been shown to worsen rather than improve after surgical CDH repair. Even after a detailed perioperative assessment, sudden cardiopulmonary failure after surgery is dangerous and requires timely and effective treatments.

Method

Three cases of cardiopulmonary failure after surgical CDH treatment in newborns have been reported. ECMO support was needed for these three patients and was successfully discontinued. We report our treatment experience.

Conclusion

ECMO is feasible for the treatment of postoperative cardiopulmonary failure in newborns with CDH.

A Tracheal Aspirate-derived Airway Basal Cell Model Reveals a Proinflammatory Epithelial Defect in Congenital Diaphragmatic Hernia

Rationale: Congenital diaphragmatic hernia (CDH) is characterized by incomplete closure of the diaphragm and lung hypoplasia. The pathophysiology of lung defects in CDH is poorly understood. Objectives: To establish a translational model of human airway epithelium in CDH for pathogenic investigation and therapeutic testing. Methods: We developed a robust methodology of epithelial progenitor derivation from tracheal aspirates of newborns. Basal stem cells (BSCs) from patients with CDH and preterm and term non-CDH control subjects were derived and analyzed by bulk RNA sequencing, assay for transposase accessible chromatin with sequencing, and air-liquid interface differentiation. Lung sections from fetal human CDH samples and the nitrofen rat model of CDH were subjected to histological assessment of epithelial defects. Therapeutics to restore epithelial differentiation were evaluated in human epithelial cell culture and the nitrofen rat model of CDH. Measurements and Main Results: Transcriptomic and epigenetic profiling of CDH and control BSCs reveals a proinflammatory signature that is manifested by hyperactive nuclear factor kappa B and independent of severity and hernia size. In addition, CDH BSCs exhibit defective epithelial differentiation in vitro that recapitulates epithelial phenotypes found in fetal human CDH lung samples and fetal tracheas of the nitrofen rat model of CDH. Furthermore, blockade of nuclear factor kappa B hyperactivity normalizes epithelial differentiation phenotypes of human CDH BSCs in vitro and in nitrofen rat tracheas in vivo. Conclusions: Our findings have identified an underlying proinflammatory signature and BSC differentiation defects as a potential therapeutic target for airway epithelial defects in CDH.

Congenital Diaphragmatic Hernia: Perinatal Prognostic Factors and Short-Term Outcomes in a Single-Center Series

Background: Many prognostic factors for CDH patients are described and validated in the current literature: the size of diaphragmatic defects, need for patch repair, pulmonary hypertension and left ventricular dysfunction are recognized as the most influencing outcomes. The aim of this study is to analyze the influence of these parameters in the outcome of CDH patients in our department and identify any further prognostic factors. Methods: An observational retrospective single-center study was conducted including all patients treated at our centre with posterolateral CDH between 01.01.1997 and 12.31.2019. The main outcomes evaluated were mortality and length of hospital stay. A univariate and multivariate analysis was performed. Results: We identified 140 patients with posterolateral CDH; 34.8% died before discharge. The overall median length of stay was 24 days. A univariate analysis confirmed that both outcomes are associated with the size of diaphragmatic defects, need for patch repair and presence of spleen-up (p < 0.05). A multivariate analysis identified that the need for patch repair and maximum dopamine dose used for cardiac dysfunction are independent parameters associated with the length of stay only (p < 0.001). Conclusions: In our series, the duration of hospitalization is longer for newborns with CDH treated with higher doses of dopamine for left ventricular dysfunction or needing patch repair in large diaphragmatic defects.

The myocardial capillary network is altered in congenital diaphragmatic hernia in the fetal rabbit model

Congenital diaphragmatic hernia (CDH) is associated with thoracic compression of the lungs and heart caused by the herniated abdominal content, leading to cardiac modifications including pressure and vascular changes. Our aim was to investigate the experimental immunoexpression of the capillary proliferation, activation, and density of Ki-67, VEGFR2, and lectin in the myocardium after surgical creation of a diaphragmatic defect. Pregnant New Zealand rabbits were operated on the 25th gestational day in order to create left-sided CDH (LCDH, n=9), right-sided CDH (RCDH, n=9), and Control (n=9), for a total of 27 fetuses in 19 pregnant rabbits. Five days after the procedure, animals were sacrificed, and histology and immunohistochemistry studies of the harvested hearts were performed. Total body weight and heart weight were not significantly different among groups (P=0.702 and 0.165, respectively). VEGFR2 expression was increased in both ventricles in the RCDH group (P<0.0001), and Ki-67 immunoexpression was increased in the left ventricle in the LCDH group compared to Control and RCDH groups (P<0.0001). In contrast, capillary density was reduced in the left ventricle in the LCDH compared to the Control and RCDH groups (P=0.002). Left and right ventricles responded differently to CDH in this model depending on the laterality of the diaphragmatic defect. This surgical model of diaphragmatic hernia was associated with different expression patterns of capillary proliferation, activation, and density in the myocardium of the ventricles of newborn rabbits.

Hemodynamic Characterization of Neonates With Congenital Diaphragmatic Hernia-Associated Pulmonary Hypertension by Cardiac Catheterization

We examined the results of cardiac catheterization in infants with congenital diaphragmatic hernia (CDH) from 2009 to 2020. Catheterization confirmed pulmonary arterial hypertension in all cases (n =  17) and identified left ventricular (LV) diastolic dysfunction (LVDD) in 53%. LVDD was associated with greater respiratory morbidity. Preprocedural noninvasive assessment showed inconsistent agreement with catheterization results.

Diagnosis & management of pulmonary hypertension in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) contributes to neonatal morbidity and mortality worldwide. Pulmonary hypertension (PH) is a key component of CDH pathophysiology and critical consideration for management and therapeutic options. PH associated with CDH has traditionally been attributed to pulmonary vascular maldevelopment and associated lung parenchymal hypoplasia, leading to pre-capillary increase in pulmonary vascular resistance (PVR). However, there is increasing recognition that left ventricular hypoplasia, dysfunction and elevated end diastolic pressure may contribute to post-capillary pulmonary hypertension in CDH patients. The interplay of these mechanisms and associated dysfunction in the right and left ventricles results in variable hemodynamic phenotypes in CDH. Clinical assessment of individual phenotype may help guide personalized management strategies, including effective use of pulmonary vasodilators and extra-corporeal membrane oxygenation. Ongoing investigation of the underlying mechanisms of PH in CDH, and efficacy of physiology-based treatment approaches may support improvement in outcomes in this challenging condition.

Supraventricular Tachycardia in Infants With Congenital Diaphragmatic Hernia: Prevalence, Associations, and Outcomes

OBJECTIVES

To characterize the prevalence, associations, management, and outcomes of supraventricular tachycardia (SVT) in neonates with congenital diaphragmatic hernia (CDH).

DESIGN

Retrospective chart and cardiology code review within a cohort of patients with CDH was used to define a subpopulation with atrial arrhythmia. SVT mechanisms were confirmed by electrocardiogram analysis. Cox proportional hazard regression identified risk factors for SVT and association with clinical outcomes.

SETTING

Medical Surgical ICU in a single, tertiary center, Boston Children's Hospital.

PATIENTS

Eligible patients included neonates presenting with classic Bochdalek posterolateral CDH between 2005 and 2017, excluding newborns with Morgagni hernia or late diagnoses of CDH (>28 d).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

SVT arose in 25 of 232 neonates with CDH, (11%); 14 of 25 infants (56%) had recurrent SVT; atrioventricular node-dependent tachycardia was the most frequent mechanism (32%). The majority (71%) of SVT episodes received intervention. Nine patients (36%) received preventative antiarrhythmic medications. SVT was associated with lower Apgar score at 1 min, structural heart disease, larger defect size, extracorporeal membrane oxygenation (ECMO) support, and prostaglandin therapy for ductal patency as well as hospital stay greater than or equal to 8 weeks and use of supplemental oxygen at discharge.

CONCLUSIONS

SVT can occur in neonates with CDH and frequently requires treatment. Odds of occurrence are increased with greater CDH disease severity, ECMO, and prostaglandin use. In unadjusted logistic regression analysis, SVT was associated with adverse hospital outcomes, underscoring the importance of recognition and management in this vulnerable population.

Congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a rare birth defect characterized by incomplete closure of the diaphragm and herniation of fetal abdominal organs into the chest that results in pulmonary hypoplasia, postnatal pulmonary hypertension owing to vascular remodelling and cardiac dysfunction. The high mortality and morbidity rates associated with CDH are directly related to the severity of cardiopulmonary pathophysiology. Although the aetiology remains unknown, CDH has a polygenic origin in approximately one-third of cases. CDH is typically diagnosed with antenatal ultrasonography, which also aids in risk stratification, alongside fetal MRI and echocardiography. At specialized centres, prenatal management includes fetal endoscopic tracheal occlusion, which is a surgical intervention aimed at promoting lung growth in utero. Postnatal management focuses on cardiopulmonary stabilization and, in severe cases, can involve extracorporeal life support. Clinical practice guidelines continue to evolve owing to the rapidly changing landscape of therapeutic options, which include pulmonary hypertension management, ventilation strategies and surgical approaches. Survivors often have long-term, multisystem morbidities, including pulmonary dysfunction, gastroesophageal reflux, musculoskeletal deformities and neurodevelopmental impairment. Emerging research focuses on small RNA species as biomarkers of severity and regenerative medicine approaches to improve fetal lung development.

Ventricular function in congenital diaphragmatic hernia: a systematic review and meta-analysis

There is emerging evidence supporting ventricular function as a prognostic factor in congenital diaphragmatic hernia (CDH). The present systematic review and meta-analysis aimed to determine the predictive value of early ventricular function for survival and extracorporeal membrane oxygenation (ECMO) requirement in newborns with CDH. PubMed, Google Scholar, Cochrane Central Register, Clinical Trial Registry, and Opengrey were accessed. Studies evaluating associations between echocardiographic ventricular function measured ≤ 48 h after birth and survival or ECMO requirement were included. Two independent authors extracted the following data: study and participant characteristics, prognostic factors, and outcome-related data. Eleven studies met the inclusion criteria. Five studies reported on survival, two on ECMO, and four on both outcomes. A moderate risk of bias was found in most of the studies, mainly because of selection, prognostic factors, and confounding biases. For survival (899 participants), pooled sensitivity and specificity were 86% (95% confidence interval [CI], 77-92%) and 44% (95% CI, 25-65%), respectively, in normal left ventricular function. For ECMO need (815 participants), pooled sensitivity and specificity were 39.8% (95% CI, 27-52%) and 88% (95% CI, 80-96%), respectively, in left ventricular dysfunction. Overall certainty of the evidence was graded very low for survival and low for ECMO. Inconsistent reporting of echocardiographic measurements and lack of adjustment for confounding factors were major limitations.Conclusion: Early ventricular dysfunction is a potential prognostic factor in CDH. Standardized echocardiographic measurement reporting and high-quality studies are needed to further elucidate its prognostic significance. What is Known: • Evidence supports the predictive value of echocardiographic measurements in CDH ≤ 24-48 h post-birth. • Ventricular dysfunction has been proposed as a prognostic risk factor. What is New: • Right and left ventricular functions were promising predictors of survival and ECMO requirement in neonates with CDH. • Test characteristics of ventricular function were determined as predictors of survival or need for ECMO. Specific echocardiographic markers of ventricular function can be valuable in determining prognosis.

Predicting treatment of pulmonary hypertension at discharge in infants with congenital diaphragmatic hernia

OBJECTIVE

To predict pulmonary hypertension (PH) therapy at discharge in a large multicenter cohort of infants with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

Six-year linked records from Children's Hospitals Neonatal Database and Pediatric Health Information System were used; patients whose diaphragmatic hernia was repaired before admission or referral, who were previously home before admission or referral, and non-survivors were excluded. The primary outcome was the use of PH medications at discharge and the secondary outcome was an inter-center variation of therapies during inpatient utilization. Clinical factors were used to develop a multivariable equation randomly applied to 80% cohort; validated in the remaining 20% infants.

RESULTS

A total of 831 infants with CDH from 23 centers were analyzed. Overall, 11.6% of survivors were discharged on PH medication. Center, duration of mechanical ventilation, and duration of inhaled nitric oxide were associated with the use of PH medication at discharge. This model performed well in the validation cohort area under the receiver operating characteristic curve of 0.9, goodness-of-fit χ², p = 0.17.

CONCLUSIONS

Clinical variables can predict the need for long-term PH medication after NICU hospitalization in surviving infants with CDH. This information may be useful to educate families and guide the development of clinical guidelines.

The heart in congenital diaphragmatic hernia: Knowns, unknowns, and future priorities

There is growing recognition that the heart is a key contributor to the pathophysiology of congenital diaphragmatic hernia (CDH), in conjunction with developmental abnormalities of the lung and pulmonary vasculature. Investigations to date have demonstrated altered fetal cardiac morphology, notably relative hypoplasia of the fetal left heart, as well as early postnatal right and left ventricular dysfunction which appears to be independently associated with adverse outcomes. However, many more unknowns remain, not least an understanding of the genetic and cellular basis for cardiac dysplasia and dysfunction in CDH, the relationship between fetal, postnatal and long-term cardiac function, and the impact on other parts of the body especially the developing brain. Consensus on how to measure and classify cardiac function and pulmonary hypertension in CDH is also required, potentially using both non-invasive imaging and biomarkers. This may allow routine assessment of the relative contribution of cardiac dysfunction to individual patient pathophysiological phenotype and enable better, individualized therapeutic strategies incorporating targeted use of fetal therapies, cardiac pharmacotherapies, and extra-corporeal membrane oxygenation (ECMO). Collaborative, multi-model approaches are now required to explore these unknowns and fully appreciate the role of the heart in CDH.

Fetal cardiac dimensions in congenital diaphragmatic hernia: relationship with gestational age and postnatal outcomes

OBJECTIVE

To serially assess fetal cardiac dimensions in congenital diaphragmatic hernia (CDH) and their relation to disease severity.

STUDY DESIGN

Retrospective analysis of CDH cases and matched controls. Mitral (MVd) and tricuspid (TVd) valve diameters, left (LV) and right (RV) ventricular length and area, Z-scores, were serially assessed at 24-26, 30-32, and 35-37 weeks gestational age (GA).

RESULTS

In CDH cases MVd, MVd Z-score, and LV area were significantly reduced at 24-26 and 35-37 weeks GA. TVd, TVd Z-score, and RV area were significantly reduced at 24-26 weeks. RV area Z-score increased with advancing GA. MVd and MVd Z-score were significantly lower at 24-26 weeks GA in CDH who had a combined outcome of death and/or ECMO.

CONCLUSIONS

LV hypoplasia in CDH is characterized by reduced MVd from 24 weeks GA. MVd, and the ratio of mitral and tricuspid valve diameters at later gestations, may be potential predictors of disease severity.

Early, Postnatal Pulmonary Hypertension Severity Predicts Inpatient Outcomes in Congenital Diaphragmatic Hernia

INTRODUCTION

Pulmonary hypertension (PH) is the major pathophysiologic consequence of congenital diaphragmatic hernia (CDH). We aimed to evaluate the association between early CDH-associated PH (CDH-PH) and inpatient outcomes.

METHODS

The CDH Study Group registry was queried for infants born 2015-2019 with echocardiograms before 48h of life. PH was categorized using echocardiographic findings: none, mild (right ventricular systolic pressure <2/3 systemic), moderate (between 2/3 systemic and systemic), or severe (supra-systemic). Univariate and multivariate analyses were performed. Adjusted Poisson regression was used to assess the primary composite outcome of mortality or oxygen support at 30 days.

RESULTS

Of 1,472 patients, 86.5% had CDH-PH: 13.9% mild (n = 193), 44.4% moderate (n = 631), and 33.2% severe (n = 468). On adjusted analysis, the primary outcome of mortality or oxygen support at 30 days occurred more frequently in infants with moderate (incidence rate ratio [IRR] 1.8, 95% confidence interval [CI], 1.2-2.6) and severe CDH-PH (IRR 2.0, 95% CI, 1.3-2.9). Extracorporeal life support (ECLS) utilization was associated only with severe CDH-PH after adjustment (IRR 1.8, 95% CI, 1.0-3.3).

DISCUSSION/CONCLUSION

Early, postnatal CDH-PH is independently associated with increased risk for mortality or oxygen support at 30 days and utilization of ECLS. Early echocardiogram is a valuable prognostic tool for early, inpatient outcomes in neonates with CDH.