Prognostic markers in congenital diaphragmatic hernia: Left ventricular diameter and pulmonary hypertension

Patterns and Outcomes of Epoprostenol Use in Infants with Congenital Diaphragmatic Hernia Requiring Extracorporeal Life Support

OBJECTIVE

To describe our experience utilizing epoprostenol for pulmonary hypertension (PH) in infants with congenital diaphragmatic hernia (CDH) requiring extracorporeal life support (ECLS).

STUDY DESIGN

We retrospectively reviewed infants diagnosed with CDH who required ECLS at our institution from 2013-2023. Data collected included demographics, disease characteristics, medication administration patterns, and hospital outcomes. We first compared infants who received intravenous epoprostenol and those who did not. Among infants who received epoprostenol, we compared survivors and non-survivors. Chi-square/Fisher's exact and Mann-Whitney tests were used, with significance p<0.05.

RESULTS

Fifty-seven infants were included; 40 (70.2%) received epoprostenol. Infants receiving epoprostenol had lower observed/expected total fetal lung volume (O/E TFLV) on MRI (20 vs. 26.2%, p=0.042) as well as higher prenatal frequency of liver-up (90 vs 64.7%, p=0.023) and "severe" classification (67.5 vs 35.3%, p=0.007). Survival with and without epoprostenol was comparable (60% vs. 64%, p=0.23). Of those receiving epoprostenol, both survivors and non-survivors had similar prenatal indicators of disease severity. Most (80%) of hernia defects were classified as Type C/D and 68% were repaired <72 hours after ECLS cannulation. The median age at initiation of epoprostenol was day of life 6 (IQR: 4, 7) in survivors and 8 (IQR: 7, 16) in non-survivors (p=0.012). Survivors had shorter ECLS duration (11 vs 20 days, p=0.049). Of non-survivors, refractory PH was the cause of death for 13 infants (81%).

CONCLUSION

In infants with CDH requiring ECLS, addition of epoprostenol appears promising and earlier initiation may affect survival.

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.

Right to left ventricular volume ratio is associated with mortality in congenital diaphragmatic hernia

BACKGROUND

Congenital diaphragmatic hernia (CDH) is associated with high neonatal mortality. We performed this study to test the hypothesis that left ventricular (LV) and right ventricular (RV) volumes assessed by three-dimensional echocardiography may be associated with mortality in CDH.

METHODS

This study was a single-center retrospective cohort study involving 35 infants with CDH. RV and LV end-diastolic volume (RVEDV and LVEDV, respectively) were measured by three-dimensional echocardiography and were corrected by birth body weight (BBW) on day 1. RVEDV/BBW, LVEDV/BBW, and LVEDV/RVEDV were compared between CDH survivors and non-survivors. Receiver-operating characteristic curve analysis was performed to assess the predictive ability for mortality of the echocardiographic parameters.

RESULTS

Comparing CDH non-survivors (n = 6) with survivors (n = 29), respectively, RVEDV/BBW was significantly larger (2.54 ± 0.33 vs 1.86 ± 0.35 ml/kg; P < 0.01), LVEDV/BBW was significantly smaller (0.86 ± 0.21 vs 1.22 ± 0.33 ml/kg; P < 0.001), and LVEDV/RVEDV was significantly lower (0.34 ± 0.06 vs 0.66 ± 0.18; P < 0.001). The area under the curve for LVEDV/RVEDV was the largest (0.98).

CONCLUSIONS

Three-dimensional echocardiographic volume imbalance between the RV and LV was remarkable in CDH non-survivors. The LVEDV/RVEDV ratio may be associated with mortality in CDH.

IMPACT

Mortality with congenital diaphragmatic hernia (CDH) is high, and evaluating left and right ventricular structures and functions may be helpful in assessing the prognosis. Three-dimensional (3D) echocardiography indicated that the left ventricular end-diastolic volume/right ventricular end-diastolic volume ratio within 24 h after birth was associated with mortality in CDH infants. The usefulness of this ratio should be validated in prospective multicenter studies involving larger numbers of patients.

The Utility of Serial Echocardiography Parameters in Management of Newborns with Congenital Diaphragmatic Hernia (CDH) and Predictors of Mortality

Ventricular dysfunction may be found in 40% of newborns with CDH, and is not only a predictor of disease severity, but also mortality and need for ECMO. We conducted this study to assess the utility of serial echocardiography in management of newborns with CDH and their survival outcomes. This is a retrospective study, wherein the demographic, clinical and echocardiographic data from our local CDH registry and hospital clinical database were analyzed to study the correlation of timed echocardiographic findings with mortality and other outcomes. Fourty-two newborns with CDH were admitted during the study period (M/F:19/23), with median gestation of 38 weeks (IQR:36-39) and birth weight of 2.83 kg (IQR 2.45-3.17). Thirty-one were left-sided, seven right, one central, and three bilateral hernias. Twelve infants (28%) died in early infancy. Three infants were excluded from analysis due to either palliation at birth or significant cardiac anomaly. A total of 137 echos from 39 infants were analyzed. Seventy percent of newborns who died and had an echo within the first 72 h, were noted to have suffered from moderate to severe PH. Birth weight < 2.8 kg, RVSP > 45.5 in the first 72 h and postoperative VIS > 23.5 and RSS > 4.3 were good predictors of mortality. Markers of elevated pulmonary pressures and cardiac function were useful in guiding therapy. Serial timed functional echocardiography (f-Echo) monitoring allows targeted therapy of patients with CDH. Birth weight, initial severity of pulmonary hypertension and postoperative RSS and VIS may be useful in predicting mortality.

Inotropic score and vasoactive inotropic score as predictors of outcomes in congenital diaphragmatic hernia: A single center retrospective study

BACKGROUND

Neonates with congenital diaphragmatic hernia (CDH) have varying degrees of pulmonary hypoplasia, pulmonary hypertension (PH) and cardiac dysfunction. These neonates frequently require vasoactive support and are at high risk for mortality and morbidity, including prolonged ventilator support, need for extracorporeal membrane oxygenation (ECMO), prolonged length of stay, and need for tracheostomy. However, identifying which infants are at increased risk can be challenging. In this study, we sought to investigate the utility of the inotropic score (IS) and vasoactive inotropic score (VIS) as tools to predict significant clinical outcomes and overall survival in patients with CDH. Additionally, we evaluated the correlation between IS/VIS and postnatal echocardiographic variables.

METHODS

This was a retrospective chart review of 57 patients with CDH whose postnatal care was based on a standardized institutional protocol. We calculated the IS/VIS at 6-, 12-, 24-, 48 hours of life (HOL), on the day of CDH repair and 24- and 48 hours after surgical repair. The association of these scores with postnatal echocardiographic markers was analyzed using Pearson's correlation and linear regression, while logistic regression was used for binary outcomes, and Cox proportional hazards regression was used to assess associations with survival.

RESULTS

We found that every one-unit increase in IS/VIS at 6 HOL was associated with 13% increase in the odds of ECMO (p = 0.034) and 10.1% increase in risk of death (p = 0.021). An increase in IS/VIS at 12-, 24- and 48-HOL was associated with posterior septal bowing in the first postnatal echocardiogram (p < 0.05 for all). Additionally, we noted an inverse relationship between IS (r = -0.281, p = 0.036) and VIS (r = -0.288, p = 0.031) on the day of repair and left ventricle (LV) systolic function in first postnatal echocardiogram. Increase in IS (r = -0.307, p = 0.024) and VIS (r = -0.285, p = 0.037) on the day of repair was associated with decreased LV function on the post-repair echocardiogram.

CONCLUSION

This retrospective study showed a significant association between IS/VIS obtained at various time points with clinical outcomes and echocardiographic findings in CDH, which could be used to guide prognosis and management in this patient population.

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.

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.

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.

Left-sided congenital diaphragmatic hernia: can we improve survival while decreasing ECMO?

BACKGROUND

Mortality and ECMO rates for congenital diaphragmatic hernia (CDH) remain ~30%. In 2016, we changed our CDH guidelines to minimize stimulation while relying on preductal oxygen saturation, lower mean airway pressures, stricter criteria for nitric oxide (iNO), and inotrope use. We compared rates of ECMO, survival, and survival without ECMO between the two epochs.

DESIGN/METHODS

Retrospective review of left-sided CDH neonates at the University of Utah/Primary Children's Hospital NICUs during pre (2003-2015, n = 163) and post (2016-2019, n = 53) epochs was conducted. Regression analysis controlled for defect size and intra-thoracic liver.

RESULTS

Following guideline changes, we identified a decrease in ECMO (37 to 13%; p = 0.001) and an increase in survival without ECMO (53 to 79%, p = 0.0001). Overall survival increased from 74 to 89% (p = 0.035).

CONCLUSION(S)

CDH management guideline changes focusing on minimizing stimulation, using preductal saturation and less aggressive ventilator/inotrope support were associated with decreased ECMO use and improved survival.

Congenital diaphragmatic hernia-associated cardiac dysfunction

There is increasing evidence that cardiac dysfunction is a key contributor to CDH pathophysiology. Dysfunction in both right and left ventricles is common in the early neonatal period, contributes to clinical disease severity, and is associated with adverse outcomes including death and ECMO use. Early and routine assessment of ventricular function and pulmonary artery pressure may guide individualized clinical decision-making, including use of pulmonary vasodilators, cardiotropes, ECMO, and timing of surgical repair. Minimizing cardiac dysfunction, whether by prenatal, postnatal or perinatal treatment strategies, may lead to improved outcome in CDH.