Pharmacokinetics of Oral Treprostinil in Children With Pulmonary Arterial Hypertension.

As part of a clinical trial, this study examined the pharmacokinetics (PK) of oral treprostinil (TRE) in children with pulmonary arterial hypertension. The trial consisted of the following 3 cohorts: transition from parenteral (cohort 1) or inhaled (cohort 2) TRE, or de novo addition (cohort 3). Oral TRE was dosed 3 times daily. PK samples were obtained before an oral TRE dose, and at 2, 4, 6, and 8 hours thereafter. The PK parameters were calculated using noncompartmental analysis. Thirty-two children (n = 10 in cohorts 1 and 2, n = 12 in cohort 3) were enrolled; the median age was 12 years (range 7-17 years), and the median weight was 42.2 kg (range 19.3-78 kg). The median oral TRE dose for all subjects was 3.8 mg (5.9, 3.5, and 4.0 mg for cohorts 1, 2, and 3, respectively). The TRE concentration versus time profile demonstrated a peak concentration at a median of 3.8 hours with wide variability. In cohort 1, oral dosing led to higher peak (5.9 ng/mL) and lower trough (1 ng/mL) concentrations than parenteral (peak 5.4 ng/mL and trough 4.2 ng/mL), but a lower mean concentration (3.61 vs. 4.46 ng/mL), likely due to variable metabolism and noncomparable dosing. Both the area under the curve and average concentration were linearly correlated with oral TRE dose and dose normalized to body weight, but not with weight or age alone. In pediatric patients, an increased oral TRE dose or dose frequency may be required to minimize PK variability and achieve greater correlation with parenteral dosing.

Compatibility of treprostinil sodium and dopamine hydrochloride during simulated Y-site administration.

PURPOSE: To evaluate the physical and chemical compatibilities of treprostinil sodium and dopamine hydrochloride. METHODS: Treprostinil sodium (4,000, 76,000, and 500,000 ng/mL) were mixed with dopamine hydrochloride (0.6, 3.2, 6, and 40 mg/mL). Samples were obtained at hours 0, 1, 2, and 4 for physical compatibility and chemical stability testing. Physical compatibility was assessed by visual examination and measurements of turbidity and pH. Drug concentrations were assessed using stability-indicating liquid chromatography mass spectrophotometry (LCMS) for treprostinil sodium and stability-indicating high-performance liquid chromatography (HPLC) for dopamine hydrochloride. RESULTS: Treprostinil sodium 4,000 and 76,000 ng/mL, when mixed with dopamine hydrochloride 0.6, 3.2, 6, and 40 mg/mL, were stable for 4 hours. Treprostinil sodium 500,000 ng/mL was stable when mixed with dopamine hydrochloride 0.6 mg/mL for 4 hours, but when mixed with dopamine hydrochloride 3.2, 6, and 40 mg/mL, significant precipitation was seen. CONCLUSION: Treprostinil sodium 4,000 and 76,000 ng/mL were stable for 4 hours during simulated Y-site coadministration with dopamine hydrochloride 0.6, 3.2, 6, and 40 mg/mL. Treprostinil sodium 500,000 ng/mL is stable when mixed with dopamine hydrochloride 0.6 mg/mL.

Echocardiographic Screening of Cardiovascular Status in Pediatric Sickle Cell Disease.

Although elevated right ventricular pressure and left ventricular diastolic dysfunction measured by echocardiogram are independent predictors of death in adults with sickle cell disease (SCD), the utility of routine echocardiographic screening in the pediatric population is controversial. We performed a 3-year retrospective review of children ≥ 10 years of age with SCD who underwent an outpatient transthoracic echocardiogram as part of a screening program. Of 172 patients referred for screening, 105 (61%) had a measurable tricuspid regurgitation jet velocity (TRV): median 2.4 m/s (IQR 2.3-2.5). Elevated right ventricular (RV) pressure (TRV ≥ 2.5 m/s, 25 mmHg), documented in 30% (32/105), was significantly associated with chronic transfusion therapy and elevated lactate dehydrogenase. Left ventricle (LV) dilation, documented in 25% (44/172), was significantly associated with lower hemoglobin, and higher reticulocyte count, lactate dehydrogenase level, and bilirubin level. There was no association between elevated right ventricular pressure or left ventricle dilation and indices of biventricular systolic or diastolic function. The one death in the cohort during the study period had normal echocardiographic findings. In conclusion, mild RV pressure elevation and LV dilation in children with SCD is associated with abnormal laboratory markers of disease severity, but not with ventricular dysfunction over the 3-year study period.

Use of prostaglandin E1 to treat pulmonary hypertension in congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: Prostaglandin E1 (PGE) has been used to maintain ductus arteriosus patency and unload the suprasystemic right ventricle (RV) in neonates with congenital diaphragmatic hernia (CDH) and severe pulmonary hypertension (PH). Here we evaluate the PH response in neonates with CDH and severe PH treated with PGE. METHODS: We performed a retrospective chart review of CDH infants treated at our center between 2011 and 2016. In a subset, PGE was initiated for echocardiographic evidence of severe PH, metabolic acidosis, or hypoxemia. To assess PH response, we evaluated laboratory data, including B-type natriuretic peptide (BNP) and echocardiograms before and after PGE treatment. Categorical and continuous data were analyzed with Fisher's exact tests and Mann-Whitney t-tests, respectively. RESULTS: Fifty-seven infants were treated with PGE a mean 17 ±â€¯2 days. BNP levels declined after 1.4 ±â€¯0.2 days of treatment and again after 5.2 ±â€¯0.6 days. After 6 ±â€¯0.8 days of treatment, echocardiographic estimates of severe PH by tricuspid regurgitation jet velocity, ductus arteriosus direction, and ventricular septum position also improved significantly. Treatment was not associated with postductal hypoxemia or systemic hypoperfusion. CONCLUSIONS: In patients with CDH and severe PH, PGE is well tolerated and associated with improved BNP and echocardiographic indices of PH, suggesting successful unloading of the RV. TYPE OF STUDY: Treatment study. LEVEL OF EVIDENCE: Level III.

Aicardi goutières syndrome is associated with pulmonary hypertension.

While pulmonary hypertension (PH) is a potentially life threatening complication of many inflammatory conditions, an association between Aicardi Goutières syndrome (AGS), a rare genetic cause of interferon (IFN) overproduction, and the development of PH has not been characterized to date. We analyzed the cardiac function of individuals with AGS enrolled in the Myelin Disorders Bioregistry Project using retrospective chart review (n = 61). Additional prospective echocardiograms were obtained when possible (n = 22). An IFN signature score, a marker of systemic inflammation, was calculated through the measurement of mRNA transcripts of type I IFN-inducible genes (interferon signaling genes or ISG). Pathologic analysis was performed as available from autopsy samples. Within our cohort, four individuals were identified to be affected by PH: three with pathogenic gain-of-function mutations in the IFIH1 gene and one with heterozygous TREX1 mutations. All studied individuals with AGS were noted to have elevated IFN signature scores (Mann-Whitney p < .001), with the highest levels in individuals with IFIH1 mutations (Mann-Whitney p < .0001). We present clinical and histologic evidence of PH in a series of four individuals with AGS, a rare interferonopathy. Importantly, IFIH1 and TREX1 may represent a novel cause of PH. Furthermore, these findings underscore the importance of screening all individuals with AGS for PH.

Treprostinil Improves Persistent Pulmonary Hypertension Associated with Congenital Diaphragmatic Hernia.

OBJECTIVE: To evaluate the effect of continuous treprostinil in infants with severe pulmonary hypertension associated with congenital diaphragmatic hernia (CDH) on specific markers of pulmonary hypertension severity and to report the safety and tolerability of treprostinil. STUDY DESIGN: We conducted a retrospective cohort study of infants with CDH-associated pulmonary hypertension treated with treprostinil from January 2011 to September 2016. Severity of pulmonary hypertension was assessed by echocardiogram and serum B-type natriuretic peptide (BNP) by using time points before initiation and 24 hours, 1 week, and 1 month after treprostinil initiation. Fisher exact tests, Wilcoxon-rank sum tests, and mixed-effects models were used for analysis. RESULTS: Seventeen patients were treated with treprostinil for a median of 54.5 days (IQR 44.3-110 days). Compared with the concurrent CDH population (n = 147), infants treated with treprostinil were more likely to require extracorporeal support (76.5% vs 25.2%, P < .0001), to have a longer hospital stay (144 vs 60 days, P < .0001), and to need longer mechanical ventilator support (76.5 vs 30.9 days, P < .0001). Following treprostinil initiation, there was a significant reduction in BNP at 1 week (1439 vs 393 pg/mL, P < .01) and 1 month (1439 vs 242 pg/mL, P = .01). Severity of pulmonary hypertension by echocardiogram improved at 1 month (OR 0.14, CI 95% 0.04-0.48, P = .002). Despite these improvements, overall mortality remained high (35%). There were no adverse events related to treprostinil, including no hypotension, hypoxia, or thrombocytopenia. CONCLUSIONS: In this cohort, treprostinil use was associated with improved severity of pulmonary hypertension assessed by echocardiogram and decreased BNP, with no significant side effects.

Disopyramide use in infants and children with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy has a range of clinical severity in children. Treatment options are limited, mainly on account of small patient size. Disopyramide is a sodium channel blocker with negative inotropic properties that effectively reduces left ventricular outflow tract gradients in adults with hypertrophic cardiomyopathy, but its efficacy in children is uncertain. A retrospective chart review of patients ⩽21 years of age with hypertrophic cardiomyopathy at our institution and treated with disopyramide was performed. Left ventricular outflow tract Doppler gradients before and after disopyramide initiation were compared as the primary outcome measure. Nine patients received disopyramide, with a median age of 5.6 years (range 6 days-12.9 years). The median left ventricular outflow tract Doppler gradient before initiation of disopyramide was 81 mmHg (range 30-132 mmHg); eight patients had post-initiation echocardiograms, in which the median lowest recorded Doppler gradient was 43 mmHg (range 15-100 mmHg), for a median % reduction of 58.2% (p=0.002). With median follow-up of 2.5 years, eight of nine patients were still alive, although disopyramide had been discontinued in six of the nine patients. Reasons for discontinuation included septal myomectomy (four patients), heart transplantation (one patient), and side effects (one patient). Disopyramide was effective for the relief of left ventricular outflow tract obstruction in children with hypertrophic cardiomyopathy, although longer-term data suggest that its efficacy is not sustained. In general, it was well tolerated. Further study in larger patient populations is warranted.

Right ventricular function mirrors clinical improvement with use of prostacyclin analogues in pediatric pulmonary hypertension.

Pulmonary hypertension (PH) causes significant morbidity and mortality in children due to right ventricular (RV) failure. We sought to determine the effect of prostacyclin analogues on RV function assessed by echocardiography in children with PH. We conducted a retrospective cohort study of children with PH treated with a prostacyclin analogue (epoprostenol or treprostinil) between January 2001 and August 2015 at our center. Data were collected before initiation of treatment (baseline) and at 1-3 and 6-12 months after. Protocolized echocardiogram measurements including tricuspid annular plane systolic excursion (TAPSE) and RV global longitudinal strain were made with blinding to clinical information. Forty-nine individuals (65% female), aged 0-29 years at the time of prostacyclin initiation were included. Disease types included pulmonary arterial hypertension (idiopathic [35%], heritable [2%], and congenital heart disease-associated [18%]), developmental lung disease (43%), and chronic thromboembolic PH (2%). Participants received intravenous (IV) epoprostenol (14%) and IV/subcutaneous (SQ) (67%) or inhaled (18%) treprostinil. Over the study period, prostacyclin analogues were associated with improvement in TAPSE ( P = 0.007), RV strain ( P < 0.001), and qualitative RV function ( P = 0.037) by echocardiogram, and BNP ( P < 0.001), functional class ( P = 0.047) and 6-min walk distance ( P = 0.001). TAPSE and strain improved at early follow up ( P = 0.05 and P = 0.002, respectively) despite minimal RV pressure change. In children with PH, prostacyclin analogues are associated with an early and sustained improvement in RV function measured as TAPSE and strain as well as clinical markers of PH severity. RV strain may be a sensitive marker of RV function in this population.

Right atrial mechanics provide useful insight in pediatric pulmonary hypertension.

Right atrial (RA) mechanics have been studied infrequently in children in the past due to technical constraints. With the advent of strain imaging, RA physiology can now be studied in greater detail. The principal aim of this study was to describe functional changes in right heart mechanics of children with idiopathic pulmonary arterial hypertension (PAH), by using new applications of RA strain. In this retrospective study, we evaluated RA mechanics of 20 patients (age range = 3-23 years) with PAH and 18 control patients. RA longitudinal strain (RALS) and longitudinal displacement (LD) were calculated by speckle-tracking echocardiography. RALS was plotted against LD, producing a characteristic strain-displacement (S-D) loop. Standard indices of right heart function and right heart catheterization data were obtained. Patients were clinically subdivided into "compensated" and "decompensated" PAH. A chart review was performed to identify patients who subsequently developed adverse outcomes, including death, awaiting or received lung and/or heart transplantation. RALS was significantly lower in decompensated PAH compared with both controls and compensated PAH. Area enclosed by S-D loops differed significantly between the compensated and decompensated PAH subgroups (5.33 [3.90-9.44] versus 1.83 [1.17-2.36], P < 0.05). S-D loop area and RALS possessed high sensitivity and specificity compared to other parameters for identifying children with PAH who subsequently developed adverse outcomes. In particular, their sensitivities and specificities were greatly superior compared to those of tricuspid annular plane systolic excursion (TAPSE). RALS may represent a useful metric for assessing right ventricular (RV) dysfunction. S-D loops, composed over an entire cardiac cycle, may present useful, composite information regarding both systolic and diastolic right heart function. RA mechanics may serve as useful tools for identifying patients with more severe PAH, who are at risk for future adverse outcomes associated with RV failure.

Transatlantic medical consultation and second opinion in pediatric cardiology has benefit past patient care: A case study in videoconferencing.

BACKGROUND: Telemedicine is a rapidly evolving form of modern information and communication technology used to deliver clinical services and educational activities. OBJECTIVE: The aim of this article is to report and analyze our experience with transatlantic consultation via videoconferencing in pediatric cardiology. METHODS: In February, 2013, videoconferencing project was launched between a medium-volume pediatric cardiac center in Bratislava, Slovakia and subspecialty experts from a high-volume pediatric cardiac program at The Children's Hospital of Philadelphia (CHOP), USA. During 1.5-2 hours videoconferences, 2-3 patients with similar complex clinical scenarios were presented to CHOP experts. The main goal of the project was consultation on individual patients to validate, alter or radically change clinical management plans. RESULTS: From February, 2013 to January, 2017, 25 videoconferences occurred and 73 cases were discussed. The median patient age was 52 months (range; 1 day-30 years). Forty-six discussed cases were outpatients, 21 patients were in the intensive care unit and 6 patients were discussed post mortem. Thirty-one CHOP experts from different subspecialties participated actively in patient consultations. The most frequent recommendations were related to single ventricle, pulmonary hypertension or heart failure patients and intervention in complex and/or rare cardiac diseases. Specialists from CHOP agreed completely with the original care plan in 16% of cases. In 52% cases, adjustments to original plan were suggested. Radical changes were recommended in 30% of cases. Receiving institution adopted recommendations to the patient care fully in 79% and partially in 13% of patients. CONCLUSIONS: Based on our 4-year experience we consider videoconferencing between medium-size pediatric cardiac center and subspecialty experts from a high-volume pediatric cardiac program a suitable form of medical consultations. Videoconferencing assists in clinical decision making for complex patient cases and serves as an effective educational tool to gain knowledge and experience "without borders."

Relationship between obstructive sleep apnea cardiac complications and sleepiness in children with Down syndrome.

OBJECTIVE/BACKGROUND: Children with Down syndrome (DS) have a high rate of pulmonary hypertension and sleepiness. They also have a high prevalence of obstructive sleep apnea syndrome (OSAS). We hypothesized that OSAS was associated with cardiovascular dysfunction and sleepiness in children with DS, and that this dysfunction was partly reversible. PATIENTS/METHODS: A total of 23 children with DS, aged 8-19 years, were evaluated with polysomnography, echocardiography, and measurement of brain natriuretic peptide (BNP). Children having OSAS were randomized to four months of actual or sham continuous positive airway pressure (CPAP) in a double-blinded fashion. RESULTS: Of the total participants, 20 (87%) had OSAS. On echocardiography, no participant was found to have pulmonary hypertension, and all participants had a BNP <10 pg/mL. The early/tissue Doppler (E/e') of the lateral mitral annulus, a measure of worse left ventricular (LV) diastolic function, correlated with the arousal index (r = 0.42, p = 0.043) and apnea hypopnea index (AHI; r = 0.61, p = 0.002) and inversely with the SpO2 nadir (r = -0.61, p = 0.002). Participants with OSAS had a high pediatric Epworth score [median interquartile range (IQR) = 8(4,9)],correlating with the arousal index (r = 0.49, p = 0.016). At four months, there were no changes in cardiovascular outcomes or sleepiness between those on actual versus sham CPAP. Hours of actual CPAP use was associated with improved E/e' mitral lateral (r = -0.48, p = 0.044), but surprisingly also correlated with LV mass z-score (r = 0.54, p = 0.018). CONCLUSIONS: In children with DS, LV diastolic function correlated with OSAS severity, with improvement with CPAP use. There was a tendency towards increased sleepiness in those with OSAS, which correlated with the arousal index. Larger studies are warranted to confirm these findings.

Pediatric Pulmonary Hypertension: Guidelines From the American Heart Association and American Thoracic Society.

Pulmonary hypertension is associated with diverse cardiac, pulmonary, and systemic diseases in neonates, infants, and older children and contributes to significant morbidity and mortality. However, current approaches to caring for pediatric patients with pulmonary hypertension have been limited by the lack of consensus guidelines from experts in the field. In a joint effort from the American Heart Association and American Thoracic Society, a panel of experienced clinicians and clinician-scientists was assembled to review the current literature and to make recommendations on the diagnosis, evaluation, and treatment of pediatric pulmonary hypertension. This publication presents the results of extensive literature reviews, discussions, and formal scoring of recommendations for the care of children with pulmonary hypertension.

Predictors of Catastrophic Adverse Outcomes in Children With Pulmonary Hypertension Undergoing Cardiac Catheterization: A Multi-Institutional Analysis From the Pediatric Health Information Systems Database.

BACKGROUND: Cardiac catheterization is the standard of care procedure for diagnosis, choice of therapy, and longitudinal follow-up of children and adults with pulmonary hypertension (PH). However, the procedure is invasive and has risks associated with both the procedure and recovery period. OBJECTIVES: The purpose of this study was to identify risk factors for catastrophic adverse outcomes in children with PH undergoing cardiac catheterization. METHODS: We studied children and young adults up to 21 years of age with PH undergoing 1 or more cardiac catheterization at centers participating in the Pediatric Health Information Systems database between 2007 and 2012. Using mixed-effects multivariable regression, we assessed the association between pre-specified subject- and procedure-level covariates and the risk of the composite outcome of death or initiation of mechanical circulatory support within 1 day of cardiac catheterization after adjustment for patient- and procedure-level factors. RESULTS: A total of 6,339 procedures performed on 4,401 patients with a diagnosis of PH from 38 of 43 centers contributing data to the Pediatric Health Information Systems database were included. The observed risk of composite outcome was 3.5%. In multivariate modeling, the adjusted risk of the composite outcome was 3.3%. Younger age at catheterization, cardiac operation in the same admission as the catheterization, pre-procedural systemic vasodilator infusion, and hemodialysis were independently associated with an increased risk of adverse outcomes. Pre-procedural use of pulmonary vasodilators was associated with reduced risk of composite outcome. CONCLUSIONS: The risk of cardiac catheterization in children and young adults with PH is high relative to previously reported risk in other pediatric populations. The risk is influenced by patient-level factors. Further research is necessary to determine whether knowledge of these factors can be translated into practices that improve outcomes for children with PH.

Trends in pediatric pulmonary hypertension-related hospitalizations in the United States from 2000-2009.

There are few data on the epidemiology of pulmonary hypertension (PH)-related hospitalizations in children in the United States. Our aim was to determine hospital mortality, length of hospitalization, and hospital charges pertaining to PH-related hospitalizations and also the effects of codiagnoses and comorbidities. A retrospective review of the Kids' Inpatient Database during the years 2000, 2003, 2006, and 2009 was analyzed for patients ≤20 years of age with a diagnosis of PH by ICD-9 (International Classification of Diseases, Ninth Revision) codes, along with associated diagnoses and comorbidities. Descriptive statistics, including Rao-Scott χ(2), ANOVA, and logistic regression models, were utilized on weighted values with survey analysis procedures. The number of PH-related hospital admissions is rising, from an estimated 7,331 (95% confidence interval [CI]: 5,556-9,106) in 2000 to 10,792 (95% CI: 8,568-13,016) in 2009. While infant age and congenital heart disease were most commonly associated with PH-related hospitalizations, they were not associated with mortality. Overall mortality for PH-related hospitalizations was greater than that for hospitalizations not associated with PH, 5.7% versus 0.4% (odds ratio: 16.22 [95% CI: 14.78%-17.8%], P < 0.001), but mortality is decreasing over time. Sepsis, respiratory failure, acute renal failure, hepatic insufficiency, arrhythmias, and the use of extracorporeal membrane oxygenation are associated with mortality. The number of PH-related hospitalizations is increasing in the United States. The demographics of PH in this study are evolving. Despite the increasing prevalence, mortality is improving.

Brain-type natriuretic peptide levels correlate with pulmonary hypertension and requirement for extracorporeal membrane oxygenation in congenital diaphragmatic hernia.

PURPOSE: B-type natriuretic peptide (BNP), an established biomarker of ventricular pressure overload, is used in the assessment of children with pulmonary hypertension (PH). PH is commonly observed in congenital diaphragmatic hernia (CDH). However, the use of BNP levels to guide treatment in this patient population has not been well defined. In this study, we investigate BNP levels in a large cohort of CDH patients treated at a single institution. METHODS: We retrospectively reviewed charts of all CDH patients enrolled in our pulmonary hypoplasia program from 2004-2013. PH was assessed by echocardiography using defined criteria, and patients were further stratified into the following cohorts: no PH, short-term PH (requiring nitric oxide but no additional vasodilatory therapy), long-term PH (requiring continued vasodilatory therapy post-discharge), and ECMO (requiring ECMO therapy). RESULTS: A total of 132 patients were studied. BNP levels were significantly increased in patients with PH compared to patients with normal pulmonary pressures (P<0.01). BNP levels were not significantly different between the ST-PH, LT-PH, and ECMO cohorts, but all levels in all three cohorts were significantly increased compared to patients who did not develop PH. CONCLUSION: Our findings indicate that plasma BNP levels correlate with pulmonary hypertension as well as the requirement for ECMO in CDH patients. Monitoring of serial BNP levels may provide a useful prognostic tool in the management of CDH.

An association between pulmonary hypertension and impaired lung function in infants with congenital diaphragmatic hernia.

RATIONALE: Infants with congenital diaphragmatic hernia (CDH) can develop pulmonary hypertension (PH) from decreased number and abnormal muscularization of pulmonary arteries. Normally pulmonary vascular growth and remodeling parallel airspace growth and alveolarization, which exhibits a wide morphologic variation in CDH. AIM: To assess whether infants with CDH and PH have greater abnormalities in infant pulmonary function testing (IPFT) compared to those without PH. METHODS: We reviewed results of IPFTs and echocardiograms performed on infants with CDH from 2004 to June 2011. Lung volumes, forced flows and tidal mechanics were standardized according to available reference values. Comparisons between infants with and without PH were performed using linear regression, adjusting for potential confounders. MAIN RESULTS: Sixty-six infants were included; 18 had PH and 48 did not. Z-score values for functional residual capacity (FRC), residual volume (RV), FRC/total lung capacity (TLC), and RV/TLC were significantly higher in infants with CDH and PH compared to those without PH. Z-score values for forced flows including forced expiratory volume in the first 0.5 sec (FEV0.5) and FEV0.5/forced vital capacity were significantly lower in infants with CDH and PH compared to those without PH. For 29 infants studied on ≥2 occasions, the slopes of FRC, RV, and TLC versus length were significantly higher in those with persistent PH compared to those without. CONCLUSIONS: Infants with CDH and persistent PH demonstrate greater airspace overdistension with growth compared to those without. Therapies that modify disrupted pulmonary vascular and alveolar formation could potentially improve future care of these patients.

Pulmonary hypertension in giant omphalocele infants.

BACKGROUND: Pulmonary hypoplasia has been described in cases of giant omphalocele (GO), although pulmonary hypertension (PH) has not been extensively studied in this disorder. In the present study, we describe rates and severity of PH in GO survivors who underwent standardized prenatal and postnatal care at our institution. METHODS: A retrospective chart review was performed for all patients in our pulmonary hypoplasia program with a diagnosis of GO. Statistical significance was calculated using Fisher's exact test and Mann-Whitney test (p<0.05). RESULTS: Fifty-four patients with GO were studied, with PH diagnosed in twenty (37%). No significant differences in gender, gestational ages, birth weight, or Apgar scores were associated with PH. Patients diagnosed with PH were managed with interventions, including high frequency oscillatory ventilation, and nitric oxide. Nine patients required long-term pulmonary vasodilator therapy. PH was associated with increased length of hospital stay (p<0.001), duration of mechanical ventilation (p=0.008), and requirement for tracheostomy (p=0.0032). Overall survival was high (94%), with significantly increased mortality in GO patients with PH (p=0.0460). Prenatal imaging demonstrating herniation of the stomach into the defect was significantly associated with PH (p=0.0322), with a positive predictive value of 52%. CONCLUSIONS: In this series, PH was observed in 37% of GO patients. PH represents a significant complication of GO, and management of pulmonary dysfunction is a critical consideration in improving clinical outcomes in these patients.

Utility of electrocardiogram in the assessment and monitoring of pulmonary hypertension (idiopathic or secondary to pulmonary developmental abnormalities) in patients≤18 years of age.

Electrocardiograms have utility in disease stratification and monitoring in adult pulmonary arterial hypertension (PAH). We examined the electrocardiographic findings that are common in pediatric PAH and assessed for correlation with disease severity and progression. We retrospectively identified patients aged≤18 years followed at a single institution from January 2001 to June 2012 with catheterization-confirmed diagnosis of idiopathic PAH and PAH secondary to pulmonary developmental abnormalities. Patients with an electrocardiography performed within 60 days of catheterization were included. Primary and secondary outcomes are the prevalence of abnormal electrocardiographic findings at the time of catheterization and the association between electrocardiographic and hemodynamic findings and electrocardiographic changes with disease progression on follow-up catheterization, respectively. Of the 100 electrocardiography-catheterization pairs derived from the 46 patients identified, 93% had an electrocardiographic abnormality: 78% had right ventricular hypertrophy (RVH) and 52% had right axis deviation (RAD) for age. In patients with idiopathic PAH, the presence of RVH and RAD correlated with pulmonary vascular resistance and transpulmonary gradient. RAD and RVH on baseline electrocardiogram was associated with an increased risk of disease progression on subsequent catheterization (odds ratio 11.0, 95% confidence interval 1.3 to 96.2, p=0.03) after adjusting for PAH subgroup. The sensitivity, specificity, and positive and negative predictive values of RAD and RVH on baseline electrocardiogram for disease progression were 92%, 48%, 33%, and 95%, respectively. In conclusion, electrocardiographic abnormalities are common in pediatric PAH. RAD and RVH on electrocardiogram were associated with worse hemodynamics, whereas their absence is suggestive of a lack of disease progression.