Hemodynamic assessment and acute pulmonary vasoreactivity testing in the evaluation of children with pulmonary vascular disease. Expert consensus statement on the diagnosis and treatment of paediatric pulmonary hypertension. The European Paediatric Pulmonary Vascular Disease Network, endorsed by ISHLT and DGPK

Delineating morbidity patterns in preterm infants at near-term age using a data-driven approach

BACKGROUND

Long-term survival after premature birth is significantly determined by development of morbidities, primarily affecting the cardio-respiratory or central nervous system. Existing studies are limited to pairwise morbidity associations, thereby lacking a holistic understanding of morbidity co-occurrence and respective risk profiles.

METHODS

Our study, for the first time, aimed at delineating and characterizing morbidity profiles at near-term age and investigated the most prevalent morbidities in preterm infants: bronchopulmonary dysplasia (BPD), pulmonary hypertension (PH), mild cardiac defects, perinatal brain pathology and retinopathy of prematurity (ROP). For analysis, we employed two independent, prospective cohorts, comprising a total of 530 very preterm infants: AIRR ("Attention to Infants at Respiratory Risks") and NEuroSIS ("Neonatal European Study of Inhaled Steroids"). Using a data-driven strategy, we successfully characterized morbidity profiles of preterm infants in a stepwise approach and (1) quantified pairwise morbidity correlations, (2) assessed the discriminatory power of BPD (complemented by imaging-based structural and functional lung phenotyping) in relation to these morbidities, (3) investigated collective co-occurrence patterns, and (4) identified infant subgroups who share similar morbidity profiles using machine learning techniques.

RESULTS

First, we showed that, in line with pathophysiologic understanding, BPD and ROP have the highest pairwise correlation, followed by BPD and PH as well as BPD and mild cardiac defects. Second, we revealed that BPD exhibits only limited capacity in discriminating morbidity occurrence, despite its prevalence and clinical indication as a driver of comorbidities. Further, we demonstrated that structural and functional lung phenotyping did not exhibit higher association with morbidity severity than BPD. Lastly, we identified patient clusters that share similar morbidity patterns using machine learning in AIRR (n=6 clusters) and NEuroSIS (n=8 clusters).

CONCLUSIONS

By capturing correlations as well as more complex morbidity relations, we provided a comprehensive characterization of morbidity profiles at discharge, linked to shared disease pathophysiology. Future studies could benefit from identifying risk profiles to thereby develop personalized monitoring strategies.

TRIAL REGISTRATION

AIRR: DRKS.de, DRKS00004600, 28/01/2013. NEuroSIS: ClinicalTrials.gov, NCT01035190, 18/12/2009.

A single institution anesthetic experience with catheterization of pediatric pulmonary hypertension patients

Cardiac catheterization remains the gold standard for the diagnosis and management of pediatric pulmonary hypertension (PH). There is lack of consensus regarding optimal anesthetic and airway regimen. This retrospective study describes the anesthetic/airway experience of our single center cohort of pediatric PH patients undergoing catheterization, in which obtaining hemodynamic data during spontaneous breathing is preferential. A total of 448 catheterizations were performed in 232 patients. Of the 379 cases that began with a natural airway, 274 (72%) completed the procedure without an invasive airway, 90 (24%) received a planned invasive airway, and 15 (4%) required an unplanned invasive airway. Median age was 3.4 years (interquartile range [IQR] 0.7-9.7); the majority were either Nice Classification Group 1 (48%) or Group 3 (42%). Vasoactive medications and cardiopulmonary resuscitation were required in 14 (3.7%) and eight (2.1%) cases, respectively; there was one death. Characteristics associated with use of an invasive airway included age <1 year, Group 3, congenital heart disease, trisomy 21, prematurity, bronchopulmonary dysplasia, WHO functional class III/IV, no PH therapy at time of case, preoperative respiratory support, and having had an intervention (p < 0.05). A composite predictor of age <1 year, Group 3, prematurity, and any preoperative respiratory support was significantly associated with unplanned airway escalation (26.7% vs. 6.9%, odds ratio: 4.9, confidence interval: 1.4-17.0). This approach appears safe, with serious adverse event rates similar to previous reports despite the predominant use of natural airways. However, research is needed to further investigate the optimal anesthetic regimen and respiratory support for pediatric PH patients undergoing cardiac catheterization.

The effects of oxygenation on acute vasodilator challenge in pulmonary arterial hypertension

Identification of long-term calcium channel blocker (CCB) responders with acute vasodilator challenge is critical in the evaluation of patients with pulmonary arterial hypertension. Currently there is no standardized approach for use of supplemental oxygen during acute vasodilator challenge. In this retrospective analysis of patients identified as acute vasoresponders, treated with CCBs, all patients had hemodynamic measurements in three steps: (1) at baseline; (2) with 100% fractional inspired oxygen; and (3) with 100% fractional inspired oxygen plus inhaled nitric oxide (iNO). Those meeting the definition of acute vasoresponsiveness only after first normalizing for the effects of oxygen in step 2 were labeled "iNO Responders." Those who met the definition of acute vasoresponsiveness from a combination of the effects of 100% FiO2 and iNO were labeled "oxygen responders." Survival, hospitalization for decompensated right heart failure, duration of CCB monotherapy, and functional data were collected. iNO responders, when compared to oxygen responders, had superior survival (100% vs. 50.1% 5-year survival, respectively), fewer hospitalizations for acute decompensated right heart failure (0% vs. 30.4% at 1 year, respectively), longer duration of CCB monotherapy (80% vs. 52% at 1 year, respectively), and superior 6-min walk distance. Current guidelines for acute vasodilator testing do not standardize oxygen coadministration with iNO. This study demonstrates that adjusting for the effects of supplemental oxygen before assessing for acute vasoresponsiveness identifies a cohort with superior functional status, tolerance of CCB monotherapy, and survival while on long-term CCB therapy.

Effect of Acute Vasodilator Testing Using Oxygen in Pulmonary Hypertension Due to Left Heart Disease

BACKGROUND

Pulmonary vasodilators, including oxygen, have not shown consistent beneficial effects on pulmonary hypertension due to valvular heart disease (PH-VHD). Therefore, the study aimed to assess the effect of 100% fractional inspiration of oxygen (FiO2) on pulmonary and systemic hemodynamics in patients with combined pre- and post-capillary pulmonary hypertension (CpcPH) and isolated post-capillary pulmonary hypertension (IpcPH) due to PH-VHD.

METHODS

This prospective study was conducted among patients with PH-VHD undergoing mitral or aortic valve replacement or repair. The study was conducted after induction of anesthesia and pulmonary artery catheterization. Cardiac output was obtained using thermodilution and all direct, and derived hemodynamic variables were obtained at 30% and 100% FiO2. The patients were stratified a priori into responders {(≥10 mmHg fall in mean pulmonary artery pressure (MPAP)} and non-responders.

RESULTS

Fifty-seven patients completed the acute vasodilator test. The mean age and body mass index of the study population was 41.8 ± 14.1 years and 21.4 ± 4.6 kg/m2, respectively. There was a significant decrease in MPAP (40.77 ± 12.07 mmHg vs 36.74 ± 13.3 mmHg; P < .001) and pulmonary vascular resistance (PVR) {(median; Interquartile range (IQR); 388; 371 vs 323; 362 dynes sec.cm-5; P < .001) at 100% FiO2. Transpulmonary gradient (TPG) and diastolic pulmonary gradient (DPG) also decreased significantly (P < .001 and P < .001). Cardiac output did not change significantly. The magnitude of decrease in MPAP, PVR, TPG, DPG, and pulmonary artery compliance (PAC) between CpcPH and IpcPH was comparable. Responders did not show a significantly greater fall in MPAP, PVR, TPG, DPG, and PAC after surgery.

CONCLUSION

Hyperoxia may lead to reduction in MPAP and PVR in both hemodynamic phenotypes of PH-VHD. A larger sample size is required to support or refute the findings of this study.

MRI pulmonary artery flow detects lung vascular pathology in preterms with lung disease

BACKGROUND

Pulmonary vascular disease (PVD) affects the majority of preterm neonates with bronchopulmonary dysplasia (BPD) and significantly determines long-term mortality through undetected progression into pulmonary hypertension. Our objectives were to associate characteristics of pulmonary artery (PA) flow and cardiac function with BPD-associated PVD near term using advanced magnetic resonance imaging (MRI) for improved risk stratification.

METHODS

Preterms <32 weeks postmenstrual age (PMA) with/without BPD were clinically monitored including standard echocardiography and prospectively enrolled for 3 T MRI in spontaneous sleep near term (AIRR (Attention to Infants at Respiratory Risks) study). Semi-manual PA flow quantification (phase-contrast MRI; no BPD n=28, mild BPD n=35 and moderate/severe BPD n=25) was complemented by cardiac function assessment (cine MRI).

RESULTS

We identified abnormalities in PA flow and cardiac function, i.e. increased net forward volume right/left ratio, decreased mean relative area change and pathological right end-diastolic volume, to sensitively detect BPD-associated PVD while correcting for PMA (leave-one-out area under the curve 0.88, sensitivity 0.80 and specificity 0.81). We linked these changes to increased right ventricular (RV) afterload (RV-arterial coupling (p=0.02), PA mid-systolic notching (t2; p=0.015) and cardiac index (p=1.67×10-8)) and correlated echocardiographic findings. Identified in moderate/severe BPD, we successfully applied the PA flow model in heterogeneous mild BPD cases, demonstrating strong correlation of PVD probability with indicators of BPD severity, i.e. duration of mechanical ventilation (rs=0.63, p=2.20×10-4) and oxygen supplementation (rs=0.60, p=6.00×10-4).

CONCLUSIONS

Abnormalities in MRI PA flow and cardiac function exhibit significant, synergistic potential to detect BPD-associated PVD, advancing the possibilities of risk-adapted monitoring.

[New aspects in pediatric pulmonary hypertension - Commented 2022ERS/ESC-PH guidelines]

Pulmonary hypertension (PH) in childhood differs from that of adulthood particularly in the specific pathophysiology of congenital heart disease-associated pulmonary arterial hypertension, the presence of developmental lung disease, and the frequent association with chromosomal, genetic, and syndromal abnormalities. Treatment of children with PH requires a modified diagnostic algorithm tailored to childhood, as well as pathophysiologically oriented therapeutic strategies. In the current 2022 ERS/ESC-PH guidelines, the specific features of PH in children are highlighted in its own chapter and commented on by the authorship group in this article.

Current diagnosis and treatment practice for pulmonary hypertension in bronchopulmonary dysplasia-A survey study in Germany (PUsH BPD)

Pulmonary hypertension (PH) is the most severe complication in preterm infants with bronchopulmonary dysplasia (BPD) and associated with significant mortality. Diagnostic and treatment strategies, however, still lack standardization. By the use of a survey study (PH in BPD), we assessed clinical practice (diagnosis, treatment, follow-up) in preterm infants with early postnatal persistent pulmonary hypertension of the newborn (PPHN) as well as at risk for or with established BPD-associated PH between 06/2018 and 10/2020 in two-thirds of all German perinatal centers with >70 very low birthweight infants/year including their cardiology departments and outpatient units. Data were analyzed descriptively by measures of locations and distributional shares. In routine postnatal care, clinical presentation and echocardiography were reported as the main diagnostic modalities to screen for PPHN in preterm infants, whereas biomarkers brain natriuretic peptide/N-terminal pro b-type natriuretic peptide were infrequently used. For PPHN treatment, inhaled nitric oxide was used in varying frequency. The majority of participants agreed to prescribe diuretics and steroids (systemic/inhaled) for infants at risk for or with established BPD-associated PH and strongly agreed on recommending respiratory syncytial virus immunization and the use of home monitoring upon discharge. Reported oxygen saturation targets, however, varied in these patients in in- and outpatient care. The survey reveals shared practices in diagnostic and therapeutic strategies for preterms with PPHN and BPD-associated PH in Germany. Future studies are needed to agree on detailed echo parameters and biomarkers to diagnose and monitor disease next to a much-needed agreement on the use of pulmonary vasodilators, steroids, and diuretics as well as target oxygen saturation levels.

Outpatient prescription of pulmonary vasodilator therapy to preterm children with bronchopulmonary dysplasia

AIM

The use of pulmonary vasodilator therapy in children born preterm is largely unknown. Our aim was to map prescription patterns in children with bronchopulmonary dysplasia in Sweden.

METHODS

This was a descriptive national registry-based study of children <7 years who had been prescribed a pulmonary vasodilator during 2007-2017, were born preterm and classified as having bronchopulmonary dysplasia. Information on prescriptions, patient characteristics and comorbidities were retrieved from the Swedish Prescribed Drug Register and linked to other national registers.

RESULTS

The study included 74 children, 54 (73%) born at 22-27 weeks' gestation and 20 (27%) at 28-36 weeks. Single therapy was most common, n = 64 (86.5%), and sildenafil was prescribed most frequently, n = 69 (93%). Bosentan, iloprost, macitentan and/or treprostinil were used mainly for combination therapies, n = 10 (13.5%). Patent ductus arteriosus or atrial septal defect were present in 29 (39%) and 25 (34%) children, respectively, and 20 (69%) versus 3 (12%) underwent closure. Cardiac catheterisation was performed in 19 (26%) patients. Median duration of therapy was 4.6 (1.9-6.8, 95% CI) months. Mortality was 9%.

CONCLUSION

Preterm children with bronchopulmonary dysplasia were prescribed pulmonary vasodilators, often without prior catheterisation. Sildenafil was most commonly used. Diagnostic tools, effects, and drug safety need further evaluation.

Long-term prognostic value of cardiac catheterization and acute vasodilator testing with inhaled iloprost in pediatric idiopathic pulmonary arterial hypertension

To assess the long-term prognostic value of cardiac catheterization and acute vasodilator testing (AVT) with inhaled iloprost in children with idiopathic pulmonary arterial hypertension (IPAH). Data on 81 consecutive children with IPAH referred to our center who underwent cardiac catheterization and AVT between June 2008 and August 2019 were collected. The correlation between the invasive hemodynamic data and transplant-free survival was analyzed. Twenty-four patients died and 1 underwent lung transplantation during a median follow-up of 3.8 years, with a 5-year transplant-free survival rate of 64.9%. Univariate analysis showed that predictors associated with improved survival included a lower pulmonary vascular resistance index (PVRI), PVRI/systemic vascular resistance index (SVRI), mean pulmonary arterial pressure (mPAP)/mean systemic arterial pressure, mean right atrial pressure, and a higher cardiac index (CI), mixed systemic venous oxygen saturations (SvO₂), and acute vasodilator response (AVR) according to the Barst criteria (decrease in mPAP and PVRI/SVRI ratio of >20% without a decrease in CI). In multivariate Cox regression analysis, Barst AVR and SvO₂ were independently related to transplant-free survival. Multiple hemodynamic variables from cardiac catheterization and AVT with inhaled iloprost have important prognostic value for long-term survival in children with IPAH, of which pulmonary vasoreactivity defined by the Barst criteria and SvO₂ are independent prognostic factors.

Safety of chronic high-dose calcium channel blockers exposure in children with pulmonary arterial hypertension

Background

Chronic calcium channel blockers (CCBs) are indicated in children with idiopathic/heritable pulmonary arterial hypertension (IPAH/HPAH) and positive response to acute vasodilator challenge. However, minimal safety data are available on the long-term high-dose exposure to CCBs in this population.

Methods

Patients aged 3 months to 18 years who were diagnosed with IPAH/HPAH and treated with CCB in the past 15 years were retrospectively reviewed. The maximum tolerated dose and the long-term safety of high-dose CCBs on the cardiovascular and noncardiovascular systems were assessed.

Results

Thirty-two eligible children were enrolled in the study, with a median age of 9 (6–11) years old. Thirty-one patients were treated with diltiazem after diagnosis. The median maximum tolerated dose was 12.9 (9.8–16.8) mg/kg/day. Children younger than 7 years used higher doses than children in the older age group, 16.4 (10.5–28.5) mg/kg/day vs. 12.7 (6.6–14.4) mg/kg/day, P < 0.05. Patients were followed up for a median period of 6.2 (2.6–10.8) years. One patient died from a traffic accident, and others showed a stable or improved WHO functional class status. Thirteen (40.6%) and 10 (31.3%) patients developed arrhythmias and hypotension. Nine (28.1%) patients had sinus bradycardia, five (21.9%) had first-degree or second-degree type II atrial-ventricular blocks, and two (6.3%) had second-degree type II atrial-ventricular blocks. Most of these arrhythmias were transient and relieved after CCB dose adjustment. The most reported noncardiovascular adverse effect was gingival hyperplasia (13, 40.6%), accompanied by different degrees of dental dysplasia. No liver or kidney dysfunction was reported.

Conclusion

Diltiazem was used in a very high dose for eligible children with IPAH/HPAH. The toxicity of long-term CCB use on the cardiovascular system is mild and controllable. Clinicians should also monitor the noncardiovascular adverse effects associated with drug therapy.

Early and long-term results of ventricular septal defect repair in children with severe pulmonary hypertension and elevated pulmonary vascular resistance by the double or traditional patch technique

OBJECTIVES

In upper-income countries, infants undergo low-risk ventricular septal defect (VSD) repair. Children in low- and middle-income countries frequently present at older ages with elevated pulmonary vascular resistance (PVR) and pulmonary arterial hypertension (PAH). Expensive interventions for pulmonary hypertensive crisis are not available, and children are often denied an operation due to the mortality risk. We report our early and late experiences with these patients who underwent VSD closure by traditional patch (TP) or double patch (DP) techniques.

METHODS

We extracted data from patients with VSD and PAH who underwent VSD closure operations from 1996 to 2016. Information regarding cardiac catheterizations, operations, time in the intensive care unit and follow-up information was found. We identified 129 children and analysed the differences between the TP (89/129) and the DP (40/129) in unidirectional groups. After 2005, the patients were pretreated with sildenafil 3 months before catheterization.

RESULTS

The TP group was younger (P  < 0.001). Hospital mortality (2.5%, DP; 10.1%,TP) was not significantly different (P  = 0.17) between the 2 groups despite significant differences in baseline PVR, PVR/systemic vascular resistance and the number of children with a saturation less than 90%. The long-term survival and regression of PAH were better in the DP group (survival over 97% vs 93% in the TP group). Moreover, 61% of children with DP and 75% of those with TP had normal to mild elevations in pulmonary artery pressures at the last follow-up examination (P  = 0.046).

CONCLUSIONS

The DP operation is a low-risk procedure. Moreover, the long-term outcome with the use of this technique in high-risk patients with VSD and high PVR and PAH is favourable with respect to survival and showed a decrease in PAH at the last follow-up.

The Clinical and Cost Utility of Cardiac Catheterizations in Infants with Bronchopulmonary Dysplasia

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.

Anesthesia in Children With Pulmonary Hypertension: Clinically Significant Serious Adverse Events Associated With Cardiac Catheterization and Noncardiac Procedures

OBJECTIVES

To determine the incidence of clinically significant serious adverse events in a contemporary population of pediatric patients with pulmonary hypertension who require anesthesia and identify factors associated with adverse outcomes.

DESIGN

A retrospective, cross-sectional study.

SETTING

A single-center quaternary-care freestanding children's hospital in the northeastern United States.

PARTICIPANTS

Pediatric patients with pulmonary hypertension based on hemodynamic criteria on cardiac catheterization during a 3-year period from 2015 to 2018.

INTERVENTIONS

Anesthesia care for cardiac catheterization, noncardiac surgery, and diagnostic imaging.

MEASUREMENTS AND MAIN RESULTS

Two hundred forty-nine children underwent 862 procedures, 592 for cardiac catheterization and 278 for noncardiac surgery and diagnostic imaging. The median age was 1.6 years, and the weight was 9.5 lbs. On index catheterization, median pulmonary artery pressure was 36 mmHg, and the pulmonary vascular resistance was 5.1 indexed Wood units. Ten percent of anesthetics were performed with a natural airway, and 80% used volatile anesthetics. Serious adverse events occurred in 26% of procedures (confidence interval [CI], 22%-30%). The rate of periprocedural cardiac arrest was 8 per 1,000 anesthetic administrations. In multivariate analysis, younger age (adjusted odds ratio [aOR], 1.4 per year; CI, 1.1-1.9; p = 0.01), location in the catheterization laboratory (aOR, 5.1; CI, 1.7-16; p = 0.004), and longer procedure duration (aOR, 1.3 per 30 minutes; CI, 1.1-1.4; p = 0.001) were associated with serious adverse events. Patients with a tracheostomy in place were less likely to experience an adverse event (aOR, 0.1; CI, 0.04-0.5; p = 0.001). The primary anesthetic technique was not associated with adverse events. Interventional cardiac catheterization was associated with an increased incidence of adverse events compared with diagnostic catheterization (42% v 21%; OR, 2.23; CI, 1.5-3.3; p < 0.001).

CONCLUSIONS

Serious adverse events were common in this cohort. Careful planning to minimize anesthesia time in young children with pulmonary hypertension should be undertaken, and these factors considered in designing risk mitigation strategies.

Vasodilator therapy for pulmonary hypertension in children: a national study of patient characteristics and current treatment strategies

Pulmonary vasodilator therapy is still often an off-label treatment for pulmonary hypertension in children. The aim of this nationwide register-based study was to assess patient characteristics and strategies for pulmonary vasodilator therapy in young Swedish children. Prescription information for all children below seven years of age at treatment initiation, between 2007 and 2017, was retrieved from the National Prescribed Drug Register, and medical information was obtained by linkage to other registers. All patients were categorized according to the WHO classification of pulmonary hypertension. In total, 233 patients had been prescribed pulmonary vasodilators. The treatment was initiated before one year of age in 61% (N = 143). Sildenafil was most common (N = 224 patients), followed by bosentan (N = 29), iloprost (N = 14), macitentan (N = 4), treprostinil (N = 2) and riociguat (N = 2). Over the study period, the prescription rate for sildenafil tripled. Monotherapy was most common, 87% (N = 203), while 13% (N = 20) had combination therapy. Bronchopulmonary dysplasia (N = 82, 35%) and/or congenital heart defects (N = 156, 67%) were the most common associated conditions. Eight percent (N = 18) of the patients had Down syndrome. Cardiac catheterization had been performed in 39% (N = 91). Overall mortality was 13% (N = 30) during the study period. This study provides an unbiased overview of national outpatient use of pulmonary vasodilator therapy in young children. Few cases of idiopathic pulmonary arterial hypertension were found, but a large proportion of pulmonary hypertension associated with congenital heart defects or bronchopulmonary dysplasia. Despite treatment, mortality was high, and additional pediatric studies are needed for a better understanding of underlying pathologies and evidence of treatment effects.

Ventricular-vascular coupling is predictive of adverse clinical outcome in paediatric pulmonary arterial hypertension

Aims

Ventricular–vascular coupling, the ratio between the right ventricle’s contractile state (E_es) and its afterload (E_a), may be a useful metric in the management of paediatric pulmonary arterial hypertension (PAH). In this study we assess the prognostic capacity of the ventricular–vascular coupling ratio (E_es/E_a) derived using right ventricular (RV) pressure alone in children with PAH.

Methods

One hundred and thirty paediatric patients who were diagnosed with PAH via right heart catheterisation were retrospectively reviewed over a 10-year period. Maximum RV isovolumic pressure and end-systolic pressure were estimated using two single-beat methods from Takeuchi et al (E_es/E_a_(Takeuchi)) and from Kind et al (E_es/E_a_(Kind)) and used with an estimate of end-systolic pressure to compute ventricular–vascular coupling from pressure alone. Patients were identified as either idiopathic/hereditary PAH or associated PAH (IPAH/HPAH and APAH, respectively). Haemodynamic data, clinical functional class and clinical worsening outcomes—separated into soft (mild) and hard (severe) event categories—were assessed. Adverse soft events included functional class worsening, syncopal event, hospitalisation due to a proportional hazard-related event and haemoptysis. Hard events included death, transplantation, initiation of prostanoid therapy and hospitalisation for atrial septostomy and Pott’s shunt. Cox proportional hazard modelling was used to assess whether E_es/E_a was predictive of time-to-event.

Results

In patients with IPAH/HPAH, E_es/E_a_(Kind) and E_es/E_a_(Takeuchi) were both independently associated with time to hard event (p=0.003 and p=0.001, respectively) and when adjusted for indexed pulmonary vascular resistance (p=0.032 and p=0.013, respectively). Neither E_es/E_a_(Kind) nor E_es/E_a_(Takeuchi) were associated with time to soft event. In patients with APAH, neither E_es/E_a_(Kind) nor E_es/E_a_(Takeuchi) were associated with time to hard event or soft event.

Conclusions

E_es/E_a derived from pressure alone is a strong independent predictor of adverse outcome and could be a potential powerful prognostic tool for paediatric PAH.

Update from the World Symposium on Pulmonary Hypertension 2018: does the new hemodynamic definition of pediatric pulmonary hypertension have an impact on treatment strategies?

Pediatric pulmonary arterial hypertension (PAH) is a progressive life-threatening disease of the pulmonary vasculature and is defined as an elevation of the mean pulmonary arterial pressure. Before the 6th World Symposium on Pulmonary Hypertension (WSPH) in 2018, pulmonary hypertension (PH) used to be defined as a mean pulmonary artery pressure (mPAP) of ≥25 mmHg. On the WSPH a revised hemodynamic definition of PH was introduced lowering the threshold for a normal mPAP from <25 to <21 mmHg. The Pediatric Task Force chose to follow this newly proposed definition of PH in order to speak a uniform language and facilitate transition to adult services. In this opinion paper we discuss the rationale behind the new PH definition and the impact on pediatric PH. We conclude, that to date, there is no evidence in children, suggesting that this decrease of threshold for PH warrants any further measures than clinical outpatient-follow-up. Hitherto, the new definition does not impact on currently applicable treatment strategies in children with PH.

Cardiac catheterization in pediatric pulmonary hypertension: a systematic and practical approach

Significant progress in the understanding of the etiology, epidemiology, pathobiology and prognosis of pulmonary hypertension (PH) has been made over the last years. Especially in the pediatric patient population the etiology of PH is very heterogeneous. Nevertheless, the most recent change of the definition of PH to a mean pulmonary artery pressure (mPAP) >20 mmHg has been accepted by pediatricians for uniformity and concordance with adult physicians. Based on the diverse underlying medical conditions leading to PH, a comprehensive and systematic approach for diagnosis and treatment is mandatory. Cardiac catheterization remains the gold standard for invasive assessment and acute vasoreactivity testing (AVT) additionally providing detailed information about nature of PH. In most patients repeat cardiac catheterization may be helpful for evaluation of response to targeted PH treatment, risk stratification and indication for lung transplantation. However, the information and results taken from cardiac catheterization should be interpreted by experienced investigators only who are familiar with confounding factors that may influence the results. Here we provide an overview of current recommendations for invasive hemodynamic evaluation in pediatric PH. We point out different patient scenarios and provide a structured approach for AVT and response interpretation.

Role of cardiovascular magnetic resonance in pediatric pulmonary hypertension-novel concepts and imaging biomarkers

Pulmonary hypertension (PH) in children is a heterogenous disease of the small pulmonary arteries characterized by a progressive increase in pulmonary vascular resistance. Despite adequate medical therapy, long-term pressure overload is frequently associated with a progressive course leading to right ventricular failure and ultimately death. Invasive hemodynamic assessment by cardiac catheterization is crucial for initial diagnosis, risk stratification and therapeutic strategy. Although echocardiography remains the most important imaging modality for the assessment of right ventricular function and pulmonary hemodynamics, cardiovascular magnetic resonance (CMR) has emerged as a valuable non-invasive imaging technique that enables comprehensive evaluation of biventricular performance, blood flow, morphology and the myocardial tissue. In this review, we summarize the principles and applications of CMR in the evaluation of pediatric PH patients and present an update about novel CMR based concepts and imaging biomarkers that may provide further diagnostic, therapeutic and prognostic information.

Hemodynamic and prognostic impact of the diastolic pulmonary arterial pressure in children with pulmonary arterial hypertension-a registry-based analysis

Background

Diastolic pulmonary arterial pressure (dPAP) is regarded to be less sensitive to flow metrics as compared to mean PAP (mPAP), and was therefore proposed for the assessment of a precapillary component in patients with postcapillary pulmonary hypertension (PH). To analyze the diagnostic and prognostic impact of dPAP in patients with pure precapillary PH, we purposed to compare the correlation between dPAP and mPAP, as well as hemodynamically-derived calculations [ratio of PAP to systemic arterial pressure (PAP/SAP), pulmonary vascular resistance index (PVRI), transpulmonary gradient (TPG)], using both dPAP and mPAP, at rest and during acute vasoreactivity testing (AVT) in children with idiopathic or heritable pulmonary arterial hypertension (IPAH/HPAH). Furthermore, we aimed to assess the association of these metrics (at baseline and changes after AVT) with transplant-free survival.

Methods

We conducted a retrospective analysis of the TOPP (Tracking Outcomes and Practice in Pediatric Pulmonary Hypertension) registry including 246 IPAH/HPAH patients. Of these, 45 children (18.3%) died, and 13 (5.3%) received lung transplantation during the observation period.

Results

dPAP and mPAP-derived variables showed almost linear relationship. Higher mPAP/mSAP, and dPAP-/mPAP-derived PVRI at rest was associated with time to death/transplantation. At maximum AVT-response, the decrease of dPAP and mPAP, diastolic pulmonary gradient (DPG) and TPG, as well as dPAP/dSAP and mPAP/mSAP was associated with time to death/transplantation, showing higher significance than corresponding baseline values. Remarkably, no predictive value was found for PVRI-reduction during AVT, neither dPAP- nor mPAP-derived.

Conclusions

There is a strong relationship between dPAP and mPAP-derived variables. According to our results, hemodynamics during AVT (irrespectively of dPAP- or mPAP-derived) may have more prognostic implications than resting hemodynamics in children with IPAH/HPAH, except for PVRI.

Systemic sclerosis-associated pulmonary arterial hypertension in children

Systemic sclerosis (SSc) is a rare disease in childhood and is characterized by a combination of vasculopathy, inflammation, autoimmunity, and fibrogenesis with individually varying expression pattern. Pulmonary arterial hypertension (PAH) is a serious complication of SSc and affects approximately 10% of SSc patients. SSc-PAH is complex and difficult to diagnose, as symptoms are non-specific and may be complicated by other SSc-associated diseases such as interstitial lung disease or left heart disease. SSc-PAH patients can deteriorate rapidly, and disease progression can occur even in patients with mild PAH symptoms at diagnosis. Therefore, interdisciplinary care of SSc patients is essential, and treating physicians must be aware of the association between SSc and PAH. In order to detect PAH early, children with SSc should be regularly screened for PAH by pediatric cardiologists. If PAH is detected, a systematic diagnostic approach by trained PH specialists including careful phenotyping of PAH is required. Relevant interstitial lung disease and left heart disease should be ruled out in the differential diagnosis of SSc-PAH before starting any targeted therapy. Due to the progressive character of SSc-PAH known from adult studies, it appears appropriate to initiate targeted PAH-therapy in juvenile SSc-PAH early. Adapted from adult treatment algorithms, combination therapy regimens (addressing at least two pathophysiological pathways) are increasingly used for pediatric PAH patients, and there is growing evidence to support this approach also in SSc-PAH patients.

Against all odds-late repair of multiple shunt lesions in a patient with Down syndrome: a case report

Background

Children with congenital heart defects (CHD) usually undergo elective surgical repair of haemodynamically relevant shunt lesions within the first year of life. Due to susceptibility for pulmonary arterial hypertension (PAH) in patients with Down syndrome, repair is usually aimed for no later than 6 months of life. However, with rising immigration from developing countries to Europe, more patients with unrepaired CHD are diagnosed at a later age. Anatomical repair may be precluded, when advanced pulmonary vascular disease has been established.

Case summary

We report a 39-month-old male patient with Down syndrome with a large non-restrictive perimembranous ventricular septal defect, a large patent ductus arteriosus, and a secundum-type atrial septal defect with a prominent left-to-right shunting. Haemodynamic assessment revealed only a mild increase of pulmonary artery pressures (mPAP) with low pulmonary vascular resistance index (PVRi). Vasodilator testing led to a further increase of the left-to-right shunt and decrease of PVRi, suggesting operability. After careful consideration, the patient underwent complete surgical repair with a good post-operative clinical outcome. Cardiac catheterization 6 months after corrective repair showed a normal mPAP. No signs of PAH have been detected in the medium-term follow-up.

Discussion

Expertise, increased physician awareness, and a thorough pre-operative multidisciplinary evaluation are paramount to determine the best treatment approach for patients, who may present late with multiple shunts, and—in our case—underlying Down syndrome. Long-term close post-surgical follow-up in an expert centre is warranted to promptly diagnose and treat a possible late presentation of PAH appropriately.

Sildenafil's Early, Late Impact on Ventricular Septal Repair: Older Children Using the Double Patch

BACKGROUND

Delayed diagnosis in children with a ventricular septal defect (VSD) is common in developing countries. Consequently, they present with elevated pulmonary vascular resistance (PVR) and pulmonary arterial hypertension (PAH). We introduced the double-flap valve VSD patch closure technique (DFV) in 1996 to reduce early post- operative risk. Long-term results are presented herein.

METHODS

This is a retrospective single-institution study on DFV patients performed between 5/1996 and 7/2015. Beginning in 2005 all candidates for DFV received sildenafil pre-and post-operatively. Pre-operative catheterization data, operative, post-operative, hospital and follow-up data were analyzed.

RESULTS

Forty patients received the DFV surgery. Patient demographics were comparable between sildenafil and non-sildenafil groups. Lost to follow up 1/39 (2.6%). Early mortality: 1/40 (2.5%), late mortality: 1/38 (2.6%). Sildenafil improved pre-op saturation, improved pre-operative hemodynamics as well as shortened prost-operative ventilation time. In both groups abnormal hemodynamic parameters improved with 100% oxygen challenge. The median age at late follow-up was 26.3 years (20.9; 29.9[25%; 75% Intra-quartile range]) and the median time since operation was 19.2 years (11.4; 22.7). Current discharge survival was 97.3%. Patients with severe PAH in late follow-up was 18%. Multi-variate analysis revealed only baseline PVR/SVR ≥ 0.8 as a significant predictor of late severe PAH.

CONCLUSIONS

Our long-term follow-up demonstrates that 60% of the patients will achieve normal or near normal PA pressures. Furthermore, we have demonstrated that sildenafil improves. pre-operative hemodynamics and post-operate management. Children with VSD, elevated PVR and PAH should not be denied operation.

Pediatric Pulmonary Hypertension: Definitions, Mechanisms, Diagnosis, and Treatment

Pediatric pulmonary hypertension (PPH) is a multifactorial disease with diverse etiologies and presenting features. Pulmonary hypertension (PH), defined as elevated pulmonary artery pressure, is the presenting feature for several pulmonary vascular diseases. It is often a hidden component of other lung diseases, such as cystic fibrosis and bronchopulmonary dysplasia. Alterations in lung development and genetic conditions are an important contributor to pediatric pulmonary hypertensive disease, which is a distinct entity from adult PH. Many of the causes of pediatric PH have prenatal onset with altered lung development due to maternal and fetal conditions. Since lung growth is altered in several conditions that lead to PPH, therapy for PPH includes both pulmonary vasodilators and strategies to restore lung growth. These strategies include optimal alveolar recruitment, maintaining physiologic blood gas tension, nutritional support, and addressing contributing factors, such as airway disease and gastroesophageal reflux. The outcome for infants and children with PH is highly variable and largely dependent on the underlying cause. The best outcomes are for neonates with persistent pulmonary hypertension (PPHN) and reversible lung diseases, while some genetic conditions such as alveolar capillary dysplasia are lethal. © 2021 American Physiological Society. Compr Physiol 11:2135-2190, 2021.

Pulmonary hypertension is an important co-morbidity in developmental lung diseases of infancy: Bronchopulmonary dysplasia and congenital diaphragmatic hernia

Bronchopulmonary dysplasia (BPD) following preterm birth and congenital diaphragmatic hernia (CDH) are both forms of developmental lung disease that may result in persistent pulmonary and pulmonary vascular morbidity in childhood. The pulmonary vascular disease (PVD) which accompanies BPD and CDH is due to developmental abnormalities and ongoing perinatal insults. This may be accompanied by evidence of elevated right heart pressures and pulmonary vascular resistance, leading to diagnosis of pulmonary hypertension (PH). The development of PH in these conditions is associated with increased morbidity and mortality in the vulnerable BPD and CDH populations. We present a review of PVD pathogenesis and evaluation in BPD and CDH and discuss management of related sequelae of PH co-morbidity for affected infants.

Focused Update on Pulmonary Hypertension in Children-Selected Topics of Interest for the Adult Cardiologist

Pulmonary hypertensive vascular disease (PHVD), and pulmonary hypertension (PH), which is a broader term, are severe conditions associated with high morbidity and mortality at all ages. Treatment guidelines in childhood are widely adopted from adult data and experience, though big differences may exist regarding aetiology, concomitant conditions and presentation. Over the past few years, paediatric aspects have been incorporated into the common guidelines, which currently address both children and adults with pulmonary hypertension (PH). There are multiple facets of PH in the context of cardiac conditions in childhood. Apart from Eisenmenger syndrome (ES), the broad spectrum of congenital heart disease (CHD) comprises PH in failing Fontan physiology, as well as segmental PH. In this review we provide current data and novel aspects on the pathophysiological background and individual management concepts of these conditions. Moreover, we focus on paediatric left heart failure with PH and its challenging issues, including end stage treatment options, such as mechanical support and paediatric transplantation. PH in the context of rare congenital disorders, such as Scimitar Syndrome and sickle cell disease is discussed. Based on current data, we provide an overview on multiple underlying mechanisms of PH involved in these conditions, and different management strategies in children and adulthood. In addition, we summarize the paediatric aspects and the pros and cons of the recently updated definitions of PH. This review provides deeper insights into some challenging conditions of paediatric PH in order to improve current knowledge and care for children and young adults.

Children and Adolescents with Pulmonary Arterial Hypertension: Baseline and Follow-Up Data from the Polish Registry of Pulmonary Hypertension (BNP-PL)

We present the results from the pediatric arm of the Polish Registry of Pulmonary Hypertension. We prospectively enrolled all pulmonary arterial hypertension (PAH) patients, between the ages of 3 months and 18 years, who had been under the care of each PAH center in Poland between 1 March 2018 and 30 September 2018. The mean prevalence of PAH was 11.6 per million, and the estimated incidence rate was 2.4 per million/year, but it was geographically heterogeneous. Among 80 enrolled children (females, n = 40; 50%), 54 (67.5%) had PAH associated with congenital heart disease (CHD-PAH), 25 (31.25%) had idiopathic PAH (IPAH), and 1 (1.25%) had portopulmonary PAH. At the time of enrolment, 31% of the patients had significant impairment of physical capacity (WHO-FC III). The most frequent comorbidities included shortage of growth (n = 20; 25%), mental retardation (n = 32; 40%), hypothyroidism (n = 19; 23.8%) and Down syndrome (n = 24; 30%). The majority of children were treated with PAH-specific medications, but only half of them with double combination therapy, which improved after changing the reimbursement policy. The underrepresentation of PAH classes other than IPAH and CHD-PAH, and the geographically heterogeneous distribution of PAH prevalence, indicate the need for building awareness of PAH among pediatricians, while a frequent coexistence of PAH with other comorbidities calls for a multidisciplinary approach to the management of PAH children.

An update on the diagnosis and treatment of pediatric pulmonary hypertension

INTRODUCTION

Pulmonary hypertension (PH) is a heterogeneous disease that mainly affects the pulmonary arterioles, leading to significant morbidity and mortality. Pulmonary hypertension in children from birth to adolescence presents important differences from that of adults. The majority of pediatric pulmonary arterial hypertension (PAH) cases are idiopathic or associated with congenital heart disease. However, the management of pediatric PAH mainly depends on the results of evidence-based adult studies and the clinical experiences of pediatric experts.

AREAS COVERED

This article briefly reviews the recent updates on the definition, classification, and diagnostic evaluation of pediatric PAH and their impact on treatment strategies. The main purpose of this review is to discuss the current pediatric therapies, as well as the prospective therapies, in terms of therapeutic targets, actions, side effects, and dosages.

EXPERT OPINION

Although there is no cure for PAH, recent advances in the form of new treatment options have improved the quality of life and survival rates of PAH patients. PAH-targeted drugs and treatment strategies for adult PAH have not been sufficiently studied in children. However, the growing scientific activity in that field will surely change the treatment option recommendations in pediatric PH from experience-based to evidence-based in the near future.

Use of Treprostinil in Pediatric Pulmonary Hypertension: Case Reports and Review of the Literature

BACKGROUND

Add-on therapy with prostacyclin in pediatric refractory pulmonary hypertension (PH) poses a challenge, especially when considering continuous intravenous administration in younger children. A search for alternate routes of drug delivery has led to the clinical investigation of stable and long-acting prostacyclin analogues, such as subcutaneous treprostinil. We reported 2 pediatric cases of PH treated with subcutaneous treprostinil and reviewed the literature on treprostinil use in children.

METHOD

The literature review used 3 electronic databases and a combination of terms (treprostinil, pediatric, PH, prostanoid, etc). We also searched for pediatric clinical trials on treprostinil registered on international clinical trial registries.

RESULTS

The reported cases highlighted the multifactorial nature of PH in pediatrics: a female child with a giant omphalocele, and intracardiac and extracardiac shunts; and a male premature child with a congenital diaphragmatic hernia and long-term PH. The literature review identified 19 studies reporting treprostinil use in 421 children with various types of PH (groups 1 and 3). Subcutaneous treprostinil was the most administered formulation, at a mean dose of 40 ng/kg/min. Overall, 12 clinical trials on treprostinil for children with PH were registered on the clinical trial registries. Most authors concluded that subcutaneous treprostinil was effective, well tolerated, and represented an alternative to intravenous epoprostenol.

CONCLUSIONS

Subcutaneous treprostinil may be a useful adjunct in the therapeutic algorithm for children with severe PH, refractory to oral drugs, and after a complete check-up for all PH etiologies.

Sex differences of hemodynamics during acute vasoreactivity testing to predict the outcomes of chronic thromboembolic pulmonary hypertension

BACKGROUND

Acute vasoreactivity testing (AVT) which reflects the compliance of the pulmonary vascular bed has been proven to be of prognostic value. The purpose of the present study is to explore the sex differences of hemodynamics during the AVT and their impact on event-free survival in patients with chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS

Eighty-six patients underwent a right heart catheterization and AVT at Shanghai Pulmonary Hospital from February 2009 to February 2018. Univariate and multiple stepwise regression analysis were performed to determine the predictors of independent event-free survival, and receiver operating characteristic curve was plotted to determine the cut-off value of independent parameters in CTEPH.

RESULTS

There were no significant differences in both demographics and hemodynamics between male and female patients with CTEPH. Except ΔPVR/PVR showed a significantly higher difference in female than male patients (P = 0.034). Male patients had higher mRAP of pre- and post-AVT than female patients in the event-free subgroup, while, female patients showed higher PVR of pre-AVT than male patients in the event subgroup (P < 0.05). The mRAP and SvO₂ were independent predictors of event-free survival in female patients both before and after the AVT, whereas ΔSvO₂ was an independent predictor of event-free survival in male patients.

CONCLUSION

Hemodynamics during the AVT varied between male and female patients with CTEPH. Both sexes displayed unique hemodynamic responses that were independently able to predict event-free survival. Therefore, better estimates of prognosis in CTEPH can be made when sex differences are also taken into consideration.

Pulmonary hypertension after shunt closure in patients with simple congenital heart defects

BACKGROUND

Patients with simple shunt lesions, such as atrial septal defect (ASD), ventricular septal defect (VSD) and persistent arterial duct (PDA) remain at risk of developing pulmonary hypertension (PH) even after correction of their cardiac defect. We aimed to assess the contemporary prevalence of PH in a well characterized nationwide group of patients based on the German National Register for Congenital Heart Defects.

METHODS AND RESULTS

We included all patients >16 years of age with an isolated diagnosis of ASD, VSD or PDA. Only patients with previous surgical or interventional closure of the defect were included. Patients with genetic syndromes were excluded. Out of 49,597 CHD patients in the register we identified 825 patients with closed, isolated simple defects (52% ASD, 41% VSD, 7% PDA). Of these, 25 (3%) developed PH after a median follow-up of 16 years from defect closure. The risk of PH increased significantly with age at follow-up (p < 0.0001) and age at repair (p < 0.0001) on logistic regression analysis Patients with PH were significantly more likely to be symptomatic (59% vs. 9% in NYHA class ≥2, p < 0.0001) and had significantly higher mortality (hazard ratio 13.4, p < 0.0001) compared to the remaining patients.

CONCLUSIONS

Based on data from the German National Register CHD Register we report a PH prevalence of 3.0% in patients with corrected, simple lesions. Patients with PH were more symptomatic and had significantly increased mortality risk. Life-long surveillance and low threshold for workup is recommended to ascertain diagnosis of PH, which has important prognostic and clinical implications.

Utility of Pulmonary Artery Acceleration Time to Estimate Systolic Pulmonary Artery Pressure in Neonates and Young Infants

Transthoracic echocardiogram (TTE) is commonly used to screen for pulmonary hypertension (PHTN) in neonates and young infants. However, in the absence of sufficient tricuspid regurgitation (TR), a ventricular septal defect (VSD), or a patent ductus arteriosus (PDA), the estimation of systolic pulmonary artery pressure (SPAP) becomes challenging. Pulmonary artery acceleration time (PAAT) is an alternate parameter that is easy to obtain in almost all patients and does not require the presence of tricuspid valvar regurgitation or an anatomical cardiac defect. We sought to examine the correlation of PAAT with estimated SPAP by TTE and create an equation to estimate the SPAP using PAAT. We performed a retrospective review of TTEs performed on neonates and young infants (4 months of age or younger) at our institution between April 2017 and December 2018, along with the corresponding medical records. We included TTEs that provided estimation for SPAP and at least one PAAT measurement. During the study period, 138 TTEs performed on 82 patients met the inclusion criteria. Strong correlation was delineated between PAAT and SPAP estimated by the maximum velocity of tricuspid valve regurgitation Doppler, correlation coefficient (r) = - 0.83. Moderate correlation was detected between PAAT and SPAP estimated by PDA Doppler, r = - 0.66. Utilizing the following equation "SPAP = 82.6 - 0.58 × PAAT + RA mean pressure", PAAT can be used to estimate SPAP in neonates and young infants. PAAT can be used as an alternative to TR jet to assess SPAP when the latter is absent or insufficient. Further studies are needed to verify the accuracy of this equation.

Neue hämodynamische Definition der pulmonalen Hypertonie

Eine pathologische Druckerhöhung im pulmonalen Gefäßsystem (pulmonale Hypertonie, PH) wurde bisher definiert durch einen invasiv gemessenen mittleren pulmonalarteriellen Druck (mPAP) ≥25 mm Hg in Ruhe. Auf dem 6th World Symposium on Pulmonary Hypertension (WSPH) in Nizza 2018 wurde eine neue Definition der PH vorgeschlagen, die die Senkung der Obergrenze des normalen mPAP von 24 auf 20 mm Hg beinhaltet.

Obwohl keine Evidenz aus pädiatrischen Studien hierfür vorliegt, wurde diese neue PH-Definition (mPAP >20 mm Hg) aus Gründen der Einheitlichkeit auch von der pädiatrischen „Task Force“ des WSPH 2018 übernommen.

Die vorliegende Stellungnahme der Arbeitsgemeinschaft Pulmonale Hypertonie (AGPH) der Deutschen Gesellschaft für Pädiatrische Kardiologie und angeborene Herzfehler e. V. (DGPK) erläutert die zugrunde liegende Rationale und mögliche Konsequenzen dieser Definitionsänderung. Insbesondere stellt sie klar, dass diese Änderung der Definition aktuell keinen Einfluss auf die Verschreibung von Medikamenten zur gezielten spezifischen Therapie der pulmonalarteriellen Hypertonie hat.

Pregnancy in adults with congenital heart disease

Congenital heart disease (CHD) is present in 0.8-0.9% of live births. Prevalence of CHD is constantly increasing during the last decades in line with the treatment options for patients ranging from the surgical as well to the interventional spectrum. Most of the women with underlying CHD reach adulthood due to excellent surgical and interventional treatment options and most of them desire pregnancy. In Western countries, maternal heart disease is the major cause of mortality during pregnancy, thus risk estimation should be therefore individualized depending on the underlying CHD, functional class and treatment options. Pre-pregnancy counselling is mandatory in all women, especially in patients with high risk but even in patients with low risk, a plan for labor and delivery should be outlined in a heart pregnancy team. This review addresses the key element of pre-counselling, planning and successful disease management in patients with CHD during pregnancy.

Pertinent clinical outcomes in pediatric survivors of pediatric acute respiratory distress syndrome (PARDS): a narrative review

The objectives of this review are to describe the limitations of commonly used clinical outcomes [e.g., mortality, ventilation parameters, need for extracorporeal membrane oxygenation (ECMO), pediatric intensive care unit (PICU) and hospital length of stay (LOS)] in pediatric acute respiratory distress syndrome (PARDS) studies; and to explore other pertinent clinical outcomes that pediatric critical care practitioners should consider in future clinical practice and research studies. These include long-term pulmonary function, risk of pulmonary hypertension (PHT), nutrition status and growth, PICU-acquired weakness, neurological outcomes and neurocognitive development, functional status, health-related quality of life (HRQOL)], health-care costs, caregiver and family stress. PubMed was searched using the following keywords or medical subject headings (MESH): "acute lung injury (ALI)", "acute respiratory distress syndrome (ARDS)", "pediatric acute respiratory distress syndrome (PARDS)", "acute hypoxemia respiratory failure", "outcomes", "pediatric intensive care unit (PICU)", "lung function", "pulmonary hypertension", "growth", "nutrition', "steroid", "PICU-acquired weakness", "functional status scale", "neurocognitive", "psychology", "health-care expenditure", and "HRQOL". The concept of contemporary measure outcomes was adapted from adult ARDS long-term outcome studies. Articles were initially searched from existing PARDS articles pool. If the relevant measure outcomes were not found, where appropriate, we considered studies from non-ARDS patients within the PICU in whom these outcomes were studied. Long-term outcomes in survivors of PARDS were not follow-up in majority of pediatric studies regardless of whether the new or old definitions of ARDS in children were used. Relevant studies were scarce, and the number of participants was small. As such, available studies were not able to provide conclusive answers to most of our clinical queries. There remains a paucity of data on contemporary clinical outcomes in PARDS studies. In addition to the current commonly used outcomes, clinical researchers and investigators should consider examining these contemporary outcome measures in PARDS studies in the future.

Chronic dosing with metformin plus bosentan decreases in vitro pulmonary artery contraction from isolated arteries in adults with pulmonary hypertension

Introduction: Pulmonary arterial hypertension (PAH) specific drug therapy using bosentan has significantly improved quality of life and survival, although PAH is still an incurable disease. Recent studies suggest metformin may have additional treatment benefits in PAH. We therefore investigated in vitro pulmonary artery reactivity after combination therapy of bosentan and metformin in PAH patients as compared with bosentan monotherapy in a prospective, randomized study.

Methods: Adult patients with PAH associated with congenital heart defects (PAH-CHD) were randomised to receive bosentan (initially at 62.5 mg twice daily for 4 weeks and then 125 mg twice daily) for 3 months with or without the combination treatment of metformin (500 mg twice daily). Vessel reactivity of isolated pulmonary arteries was examined using a wire myograph.

Results: Phenylephrine (PE)-induced contractions of arteries in patients received combination therapy were significantly attenuated at concentrations of 3 × 10^-7 M, 10^-6 M and 3 × 10^-6 M, compared to those received bosentan monotherapy. After denudation, PE-induced contractions at concentrations of 3 × 10^-6 M and 10^-5 M were significantly decreased in the combination therapy group. AMP-activated protein kinase (AMPK) inhibitor compound C abrogated the inhibitory effects of metformin on PE-induced contractility. AMPK and eNOS phosphorylation in the pulmonary arteries of patients treated with combination therapy was increased compared to monotherapy (P < 0.05).

Conclusion: Adding metformin to bosentan therapy in patients with PAH-CHD decreased in vitro pulmonary artery contraction induced by PE, which is possibly related to increased AMPK phosphorylation.

Predictors of operability in children with severe pulmonary hypertension associated with congenital heart disease

BACKGROUND

Pulmonary artery hypertension associated with congenital heart disease (PAH-CHD) occurs predominantly among patients with uncorrected CHD. Treatment of severe pediatric PAH-CHD remains a major intractability. This study evaluated the predictors and prognoses of children with PAH-CHD who underwent surgical correction.

METHODS

The data for 59 children with severe PAH-CHD who underwent surgical correction, with or without postoperative medication, between May 2011 and June 2015 at the Guangdong Provincial People's Hospital were analyzed retrospectively. A regression analysis, receiver-operating characteristic (ROC) curves, and Kaplan-Meier curves were used for survival analysis.

RESULTS

Fifty-nine children with severe PAH-CHD underwent heart catheterization and correction, with or without specific anti-PAH drugs postoperatively, were included in this study. The pulmonary pressure, heart function, and ending events were observed and median observation period was 49 ± 20 months. Twenty-eight patients (50%) received at least one additional anti-PAH drug after correction. The survival rate after 2 years was 91.5% (54/59); two patients were in a critical condition, and three were lost to follow-up. Twelve patients (29%) still received over one additional PAH-specific therapy at follow-up, whereas 42 (75%) had successfully stopped drug treatment. Two patients (3.5%) died and one underwent a second thoracotomy to remove the ventricular septal defect patch. Acute vasoreactivity test (AVT) criteria had limited efficacy in predicting pediatric PAH-CHD, whereas pulmonary vascular resistance (PVR) ≤ 6.65 Wood units (WU)/m or PVR/systemic vascular resistance (SVR) ≤ 0.39 during AVT indicated a good prognosis after surgical correction with an AUC of 98.3% (95% confidence interval [CI]: 96.0-100%), 98.4% (95% CI: 96.0-100%) sensitivity of 100%, 100% and specificity of 82.1%, 92.9%, respectively.

CONCLUSIONS

Although the criteria for positive AVT currently used are unsuitable for pediatric patients with PAH-CHD, PVR and PVR/SVR during AVT are excellent predictors of outcome in pediatric PAH-CHD. Surgery aided by anti-PAH drugs is an effective strategy and should be recommended for severe pediatric PAH-CHD with PVR ≤ 6.65 WU/m and PVR/SVR ≤ 0.39 after iloprost aerosol inhalation.

Methodology for Hemodynamic Assessment of a Three-Dimensional Printed Patient-Specific Vascular Test Device

Assessing hemodynamics in vasculature is important for the development of cardiovascular diagnostic parameters and evaluation of medical devices. Benchtop experiments are a safe and comprehensive preclinical method for testing new diagnostic endpoints and devices within a controlled environment. Recent advances in three-dimensional (3D) printing have enhanced benchtop tests by allowing generation of patient-specific and pathophysiologic conditions. We used 3D printing, coupled with image processing and computer-aided design (CAD), to develop a patient-specific vascular test device from clinical data. The proximal pulmonary artery (PA) tree including the main, left, and right pulmonary arteries, with a stenosis within the left PA was selected as a representative anatomy for developing the vascular test device. Three test devices representing clinically relevant stenosis severities, 90%, 80%, and 70% area stenosis, were evaluated at different cardiac outputs (COs). A mock circulatory loop (MCL) generating pathophysiologic pulmonary pressure and flow was used to evaluate the hemodynamics within the devices. The dimensionless pressure drop–velocity ratio characteristic curves for the three stenosis severities were obtained. At a fixed CO, the dimensionless pressure drop increased nonlinearly with an increase in (a) the velocity ratio for a fixed stenosis severity and (b) the stenosis severity at a specific velocity ratio. The dimensionless pressure drop observed in vivo was similar (within 1%) to that measured in moderate area stenosis of 70% because both flows were viscous dominated. The hemodynamics of the 3D printed test device can be used for evaluating diagnostic endpoints and medical devices in a preclinical setting under realistic conditions.

2019 updated consensus statement on the diagnosis and treatment of pediatric pulmonary hypertension: The European Pediatric Pulmonary Vascular Disease Network (EPPVDN), endorsed by AEPC, ESPR and ISHLT

The European Pediatric Pulmonary Vascular Disease Network is a registered, non-profit organization that strives to define and develop effective, innovative diagnostic methods and treatment options in all forms of pediatric pulmonary hypertensive vascular disease, including pulmonary hypertension (PH) associated with bronchopulmonary dysplasia, PH associated with congenital heart disease (CHD), persistent PH of the newborn, and related cardiac dysfunction. The executive writing group members conducted searches of the PubMed/MEDLINE bibliographic database (1990-2018) and held face-to-face and web-based meetings. Ten section task forces voted on the updated recommendations, based on the 2016 executive summary. Clinical trials, meta-analyses, guidelines, and other articles that include pediatric data were searched using the term "pulmonary hypertension" and other keywords. Class of recommendation (COR) and level of evidence (LOE) were assigned based on European Society of Cardiology/American Heart Association definitions and on pediatric data only, or on adult studies that included >10% children or studies that enrolled adults with CHD. New definitions by the World Symposium on Pulmonary Hypertension 2018 were included. We generated 10 tables with graded recommendations (COR/LOE). The topics include diagnosis/monitoring, genetics/biomarkers, cardiac catheterization, echocardiography, cardiac magnetic resonance/chest computed tomography, associated forms of PH, intensive care unit/lung transplantation, and treatment of pediatric PH. For the first time, a set of specific recommendations on the management of PH in middle- and low-income regions was developed. Taken together, these executive, up-to-date guidelines provide a specific, comprehensive, detailed but practical framework for the optimal clinical care of children and young adults with PH.

EXPRESS: Acute Vasoreactivity Testing in Pediatric Idiopathic Pulmonary Arterial Hypertension: an international Survey on Current Practice

The aim of this study was to determine practice patterns and inter-institutional variability in how acute vasoreactivity testing (AVT) is performed and interpreted in pediatrics throughout the world. A survey was offered to physicians affiliated with the Pediatric & Congenital Heart Disease Taskforce of the Pulmonary Vascular Research Institute (PVRI), the Pediatric Pulmonary Hypertension Network (PPHNET), or the Spanish Registry for Pediatric Pulmonary Hypertension (REHIPED), from February to December 2016. The survey requested data about the site-specific protocol for AVT and subsequent management of pediatric patients with idiopathic pulmonary arterial hypertension (IPAH) or heritable PAH (HPAH). Twenty-eight centers from 13 countries answered the survey. AVT is performed in most centers using inhaled nitric oxide (iNO). Sitbon criteria was used in 39% of the centers, Barst criteria in 43%, and other criteria in 18%. First-line therapy for positive AVT responders in functional class (FC) I/II was calcium channel blocker (CCB) in 89%, but only in 68% as monotherapy. Most centers (71%) re-evaluated AVT-positive patients hemodynamics after 6–12 months; 29% of centers re-evaluated based only on clinical criteria. Most centers (64%) considered a good response as remaining in FC I or II, with near normalization of pulmonary arterial pressure and pulmonary vascular resistance, but a stable FC I/II alone was sufficient criteria in 25% of sites. Protocols and diagnostic criteria for AVT, and therapeutic approaches during follow-up, were highly variable across the world. Reported clinical practice is not fully congruent with current guidelines, suggesting the need for additional studies that better define the prognostic value of AVT for pediatric IPAH patients.

Current understanding and perioperative management of pediatric pulmonary hypertension

Pediatric pulmonary hypertension is a complex disease with multiple, diverse etiologies affecting the premature neonate to the young adult. Pediatric pulmonary arterial hypertension, whether idiopathic or associated with congenital heart disease, is the most commonly discussed form of pediatric pulmonary hypertension, as it is progressive and lethal. However, neonatal forms of pulmonary hypertension are vastly more frequent, and while most cases are transient, the risk of morbidity and mortality in this group deserves recognition. Pulmonary hypertension due to left heart disease is another subset increasingly recognized as an important cause of pediatric pulmonary hypertension. One aspect of pediatric pulmonary hypertension is very clear: anesthetizing the child with pulmonary hypertension is associated with a significantly heightened risk of morbidity and mortality. It is therefore imperative that anesthesiologists who care for children with pulmonary hypertension have a firm understanding of the pathophysiology of the various forms of pediatric pulmonary hypertension, the impact of anesthesia and sedation in the setting of pulmonary hypertension, and anesthesiologists' role as perioperative experts from preoperative planning to postoperative disposition. This review summarizes the current understanding of pediatric pulmonary hypertension physiology, preoperative risk stratification, anesthetic risk, and intraoperative considerations relevant to the underlying pathophysiology of various forms of pediatric pulmonary hypertension.

Partial anomalous pulmonary venous return: A case series with management approach

Partial anomalous pulmonary venous return (PAPVR) is a rare congenital anomaly that results in a left-to-right shunt. Based on the shunt fraction, PAPVR has a wide spectrum of presentations. If a significant left-to-right shunt is left unrepaired, pulmonary vascular remodeling can occur resulting in the development of pulmonary arterial hypertension (PAH). Furthermore, if the condition is associated with an atrial septal defect (ASD), the patient can develop shunt reversal and Eisenmenger's syndrome in setting of severe PAH. Management plans include close observation, surgical repair, and treatment with pulmonary artery vasodilator therapies. Here, we present multiple cases of PAPVR to highlight the wide spectrum of presentations and the individualized treatment for each case.

Diagnosis and treatment of pediatric pulmonary arterial hypertension

INTRODUCTION

Pediatric pulmonary arterial hypertension (PAH) remains a rare and severe disease with a poor prognosis. PAH may be idiopathic, heritable or associated with systemic conditions in particular associated with congenital heart disease. Areas covered: A thorough and extensive diagnostic approach is required for a correct diagnosis. The outcome has improved over the last decade with a better diagnostic approach and with the initiation of new targeted therapies. However, there is still significant progress to achieve as there is still no cure for this devastating disease. Expert opinion: Adapted clinical studies to define the best therapeutic approach are needed. Even if the treatment approach is still mainly derived from adult data and expert consensus, several studies and registries are currently underway and should deliver important information in the next future. This review aims to give an overview of the current diagnosis and treatment strategies of PAH.

Paediatric pulmonary arterial hypertension: updates on definition, classification, diagnostics and management

Paediatric pulmonary arterial hypertension (PAH) shares common features of adult disease, but is associated with several additional disorders and challenges that require unique approaches. This article discusses recent advances, ongoing challenges and distinct approaches for the care of children with PAH, as presented by the Paediatric Task Force of the 6th World Symposium on Pulmonary Hypertension. We provide updates of the current definition, epidemiology, classification, diagnostics and treatment of paediatric PAH, and identify critical knowledge gaps. Several features of paediatric PAH including the prominence of neonatal PAH, especially in pre-term infants with developmental lung diseases, and novel genetic causes of paediatric PAH are highlighted. The use of cardiac catheterisation as a diagnostic modality and haemodynamic definitions of PAH, including acute vasoreactivity, are addressed. Updates are provided on issues related to utility of the previous classification system to reflect paediatric-specific aetiologies and approaches to medical and interventional management of PAH, including the Potts shunt. Although a lack of clinical trial data for the use of PAH-targeted therapy persists, emerging data are improving the identification of appropriate targets for goal-oriented therapy in children. Such data will likely improve future clinical trial design to enhance outcomes in paediatric PAH.

Vasoreactive Pulmonary Arterial Hypertension Manifesting With Misleading Epileptic Seizure: Diagnostic and Treatment Pitfalls

A 5-year-old girl presented with acute nocturnal episodes of loss of consciousness following abdominal pain and crying. Epilepsy was primarily diagnosed but the course of the disease was suggestive of pulmonary hypertension. An adapted invasive assessment of pulmonary pressure and pharmacological challenge allowed for diagnosing vasoreactive pulmonary arterial hypertension. Initial treatment with sildenafil was not effective. Thus, calcium channel blockers were introduced when positive vasoreactivity was confirmed and permitted to stop the occurrence of the syncope and dramatically improved clinical status. At 2 years follow-up she is well without any complaint and in functional class I. Echocardiography shows a slightly enlarged but not hypertrophied right ventricle with a nearly normalized estimated right ventricular pressure. The last catheterization shows subnormal values of pulmonary arterial pressure (mean pulmonary artery pressure: 24 mmHg) and pulmonary vascular resistance (5, 4 Wood units^*m²), normalizing with inhaled Nitric Oxide (mean pulmonary artery pressure of 14 mmHg and pulmonary vascular resistance of 1.5 Wood units^*m²). Vasoreactive pulmonary arterial hypertension is a rare entity in children but it should not be misdiagnosed with seizures due to the presence of syncopal episodes. According to current knowledge, this form seems to have a better prognosis than non-reactive pulmonary arterial hypertension and the treatment of choice remains as calcium channel blockers. The management of this case was characterized by successive mishaps and potentially harmful mistakes and underscores the potential risk with pediatric PH evaluation in non-expert centers.

How to evaluate patients with congenital heart disease-related pulmonary arterial hypertension

INTRODUCTION

Patients with congenital heart disease (CHD), who develop pulmonary arterial hypertension (PAH), live longer, and have better quality of life compared to the past due to PAH-specific therapy and improved tertiary care. Areas covered: Clinical examination, objective assessment of functional capacity, natriuretic peptide levels, cardiac imaging, and hemodynamics all play a pivotal role in the evaluation, general care, and management of PAH-specific therapy. This review discusses the epidemiology and pathophysiology of PAH-CHD and provides hints for the optimal evaluation of these patients. Expert commentary: Further research should be performed in the field of PAH-CHD, as there are many of areas lacking evidence that should be addressed in the future. Networking, especially among the tertiary expert centers, could play a key role in this direction.

Impact of the Right Ventricular Sokolow-Lyon Index in Children with Idiopathic Pulmonary Arterial Hypertension

Right ventricular (RV) hypertrophy is regarded as the adaptation on chronic RV pressure load in pulmonary hypertension. As the RV Sokolow-Lyon index (RVSLI) is an electrocardiographic marker of RV hypertrophy, we hypothesized that RVSLI might be able to reflect RV pressure load. Therefore, the purpose of this study was to characterize the diagnostic impact of the RVSLI in children with idiopathic pulmonary arterial hypertension (IPAH) in order to assess disease severity and to evaluate its value for the prediction of worse outcome. Forty-two children (aged 3-17 years) with IPAH were included in this retrospective study. The follow-up after baseline examination was 59 ± 17 months. Receiver-operating characteristic (ROC) curves and Kaplan-Meier analysis were used to discriminate a cut-off value of RVSLI and to assess its predictive value regarding morbidity and mortality. In 12/42 patients (29%) severe cardiovascular events (defined as death, lung transplantation, or Potts shunt) were observed (time to event 20 ± 22 months). Patients with an event showed higher RVSLI values (3.6 ± 1.2 mV vs. 2.6 ± 1.6 mV; p < 0.05). ROC analysis discriminated an RVSLI of 2.1 as the best cut-off value (area under the ROC curve: 0.79, sensitivity: 0.91, specificity: 0.70, p < 0.05) to detect patients with high-risk PAH (mPAP/mSAP ratio > 0.75). Relative risk for a severe event with an index > 2.1 mV was 1.76 (95% CI 1.21-3.20). Relative risk for death with RVSLI > 2.1 mV was 2.01 (95% CI 1.61-4.80). Our study demonstrates a strong relationship between RVSLI and disease severity in children with IPAH. An RVSLI > 2.1 mV at the time of first diagnosis is a predictor for patients at risk for cardiac events. As an adjunct to the usual diagnostic assessment this parameter may therefore contribute to the initial prognostic estimation.