Pulmonary hypertension in extremely preterm infants: a call to standardize echocardiographic screening and follow-up policy

Longitudinal echocardiographic parameters for evaluation of pulmonary hypertension in preterm infants with very low birth weight

BACKGROUND

Echocardiography is essential for the evaluation of pulmonary hypertension. We determined the feasible quantitative parameter for screening and monitoring pulmonary hypertension in preterm infants.

METHODS

This secondary analysis of a prospective cohort single-centre study was conducted between August 2019 and September 2020. Serial echocardiography was performed 7 and 28 days after birth and at 36 weeks postmenstrual age. The data of infants who developed pulmonary hypertension at 36 weeks postmenstrual age were compared with those without pulmonary hypertension. We also modelled the parameters' trend and performed an interaction test using multi-level Gaussian regression.

RESULTS

Out of 30 infants enrolled in the study, 79 echocardiograms were analysed. Left ventricular eccentric index was obtainable in all infants, while tricuspid jet velocity was measurable in 44.1%. Left ventricular eccentric index correlated well with tricuspid regurgitation jet velocity (r = 0.77, P < 0.001). Six infants were diagnosed with newly developed or persistent pulmonary hypertension at 36 weeks postmenstrual age. Serial left ventricular eccentric index showed a significantly different increasing trend in the pulmonary hypertension group (change per day: +0.004; P = 0.090) from the decreasing trend among a non-pulmonary hypertension group (change per day: -0.001; P = 0.041) (P for interaction = 0.007). Right ventricular systolic function and right ventricular isovolumic systolic velocity revealed a reducing trend in the pulmonary hypertension group, which was different from the improving trend in non-pulmonary hypertension infants. Infants with low current weight, low postmenstrual age, and requiring high-flow oxygen therapy at day 28 of life trended to increase the risk of late pulmonary hypertension.

CONCLUSION

Left ventricular eccentric index and right ventricular isovolumic systolic velocity were feasible for assessing pulmonary hypertension and should be incorporated into pulmonary hypertension evaluation. Serial left ventricular eccentric index and right ventricular isovolumic systolic velocity may help predict late pulmonary hypertension and early detection of right ventricular dysfunction.

Long-term impact of late pulmonary hypertension requiring medication in extremely preterm infants with severe bronchopulmonary dysplasia

This study investigated whether late pulmonary hypertension (LPH) independently increases the risk of long-term mortality or neurodevelopmental delay (NDD) in extremely preterm infants (EPIs) with severe bronchopulmonary dysplasia (BPD). Using prospectively collected data from the Korean Neonatal Network, we included EPIs with severe BPD born at 22-27 weeks' gestation between 2013 and 2021. EPIs having severe BPD with LPH (LPH, n = 124) were matched 1:3 with those without pulmonary hypertension (PH) as controls (CON, n = 372), via propensity score matching. LPH was defined as PH with the initiation of medication after 36 weeks' corrected age (CA). Long-term mortality after 36 weeks' CA or NDD at 18-24 months' CA was analyzed. NDD was assessed using composite scores based on various neurodevelopmental assessment modalities. LPH had significantly higher long-term mortality or NDD (45.2% vs. 23.1%, P < 0.001), mortality (24.2% vs. 4.84%, P < 0.001), and NDD (68.4% vs. 37.8%, P = 0.001), respectively than CON, even after adjusting for different demographic factors. Multivariable regression demonstrated that LPH independently increased the risk of mortality or NDD (adjusted odds ratio, 1.95; 95% confidence intervals, 1.17-3.25). When LPH occurs in EPIs with severe BPD, special monitoring and meticulous care for long-term survival and neurodevelopment are continuously needed.

Early Pulmonary Hypertension in Preterm Infants

Pulmonary hypertension (PH) in preterm neonates has multifactorial pathogenesis with unique characteristics. Premature surfactant-deficient lungs are injured following exposure to positive pressure ventilation and high oxygen concentrations resulting in variable phenotypes of PH. The prevalence of early PH is variable and reported to be between 8% and 55% of extremely preterm infants. Disruption of the lung development and vascular signaling pathway could lead to abnormal pulmonary vascular transition. The management of early PH and the off-label use of selective pulmonary vasodilators continue to be controversial.

Bronchopulmonary dysplasia - associated pulmonary hypertension: An updated review

Bronchopulmonary dysplasia (BPD) is the leading cause of chronic lung disease in infants and the commonest complication of prematurity. Advances in respiratory and overall neonatal care have increased the survival of extremely low gestational age newborns, leading to the continued high incidence of BPD. Pulmonary hypertension (PH) represents the severe form of the pulmonary vascular disease associated with BPD, and affects almost one-third of infants with moderate to severe BPD. PH responds suboptimally to pulmonary vasodilators and increases morbidity and mortality in BPD infants. An up-to-date knowledge of the pathogenesis, pathophysiology, diagnosis, treatment, and outcomes of BPD-PH can be helpful to develop meaningful and novel strategies to improve the outcomes of infants with this disorder. Therefore, our multidisciplinary team has attempted to thoroughly review and summarize the latest advances in BPD-PH in preventing and managing this morbid lung disorder of preterm infants.

Successful treatment of pulmonary hypertension in a neonate with bronchopulmonary dysplasia: A case report and literature review

BACKGROUND

Pulmonary hypertension (PH) is a severe complication of bronchopulmonary dysplasia (BPD) in premature neonates and is closely related to prognosis. However, there is no effective and safe treatment for PH due to BPD in infants. Successful treatment for cases of BPD-associated PH with Tadalafil combined with bosentan is rare. This case may make a significant contribution to the literature because PH is difficult to manage as a serious complication of BPD in preterm infants. Mortality is high, especially when it is complicated by heart failure.

CASE SUMMARY

An extremely premature neonate with a gestational age of 26⁺⁵ wk and birth weight of 0.83 kg was diagnosed with BPD associated with PH; oral sildenafil did not improve the PH. The infant experienced sudden cardiac arrest and serious heart failure with severe PH. After a series of treatments, including cardiopulmonary resuscitation, mechanical ventilation, and inhaled nitric oxide (iNO), the respiratory and circulatory status improved but the pulmonary artery pressure remained high. Then oral sildenafil was replaced with oral tadalafil and bosentan; pulmonary artery pressure improved, and the infant recovered at our hospital. After 2 years of follow-up, she is in good condition, without any cardiovascular complications.

CONCLUSION

INO can effectively improve the respiratory and circulatory status of infants with PH associated with premature BPD. B-type natriuretic peptide should be routinely measured during hospitalization to evaluate the risk and prognosis of BPD-associated PH in preterm infants. Tadalafil combined with bosentan for the treatment of PH associated with premature BPD was better than sildenafil in this case. Further studies are needed to explore the efficacy and safety of different vasodilators in the treatment of PH associated with premature BPD.

Imaging in neonatal respiratory disease

The purpose of this review is to describe the current state of the art in clinical imaging for NICU patients, divided into major areas that correspond to likely phenotypes of neonatal respiratory disease: airway abnormalities, parenchymal disease, and pulmonary vascular disease. All common imaging modalities (ultrasound, X-ray, CT, and MRI) are discussed, with an emphasis on modalities that are most relevant to the individual underlying aspects of disease. Some promising aspects of dynamic and functional imaging are included, where there may be future clinical applicability.

The role of bedside functional echocardiography in the assessment and management of pulmonary hypertension

Pulmonary hypertension is an emergency in neonatal intensive care units with high morbidity and mortality. Its timely assessment and management is crucial for intact survival. Over the last couple of decades, there have been significant advances in management and techniques, which have resulted in improved survival. The use of neonatologist-performed echocardiography (NPE) is now increasingly utilized on neonatal intensive care units to understand the pathophysiology of the disease and to direct the treatment to the underlying cause. Its use is now established not only in cases of congenital diaphragmatic hernia and in the newborn with refractory hypoxemia, but also in other conditions such as bronchopulmonary dysplasia and the premature infant with difficulty in oxygenation. The use of NPE, however, requires the availability of trained personnel, equipment, and a close working relationship with pediatric cardiology.

[Expert consensus on the follow-up management of bronchopulmonary dysplasia in preterm infants after discharge]

Bronchopulmonary dysplasia (BPD) is a common chronic lung disease in preterm infants and seriously affects the quality of life of preterm infants. BPD is a life-threatening disease to preterm infants and may lead to serious sequelae including feeding difficulties, recurrent lower respiratory tract infection, airway hyperreactive diseases, growth retardation, and neurodevelopmental delay. In order to further standardize the follow-up management of preterm infants with BPD after discharge, based on related clinical evidence in China and overseas and practice experience, the Neonatal Evidence-Based Medicine Group, Committee of Neonatal Medicine, Cross-Strait Medical and Health Exchange Association, formulated this expert consensus from the aspects of the follow-up and management of respiratory diseases, growth and development, pulmonary hypertension, nerve dysplasia, metabolic bone disease, and vaccination of preterm infants with BPD after discharge.