Pulmonary hypertension after operations for congenital heart disease: analysis of risk factors and management

Pulmonary artery systolic pressure associated with inflammatory factors among pediatric congenital heart disease with pulmonary arterial hypertension after cardiopulmonary bypass

OBJECTIVE

This study aimed to evaluate the perioperative inflammatory cytokines in pediatric patients with pulmonary arterial hypertension secondary to congenital heart disease and also sought to investigate the correlation between preoperative echocardiographic pulmonary artery systolic pressure and inflammatory factors after cardiopulmonary bypass in these patients.

METHODS

A retrospective observational study was conducted involving 59 children under 2 years old. Echocardiography was used to measure tricuspid annular peak systolic velocity. The levels of perioperative inflammatory cytokines in the plasma, including IL-6, IL-8, IL-10, IL-1β, and TNF-α, were measured. Additionally, postoperative ventilation time, length of intensive care unit stay, and ward stay were recorded.

RESULTS

Patients with pulmonary hypertension experience longer postoperative ventilation time, intensive care unit stay, and ward stay. Although no significant differences were observed in the cardiopulmonary bypass and aortic cross-clamping, there was a more pronounced increase in postoperative inflammatory cytokines, including IL-6, IL-8, and IL-10, in these patients following cardiopulmonary bypass (p < 0.05). Preoperative echocardiographic pulmonary artery systolic pressure was found to be associated with the levels of IL-6 and IL-10 after surgery in pulmonary hypertension patients. A pulmonary artery systolic pressure greater than 52 mmHg was able to predict a postoperative ventilation time exceeding 21 h.

CONCLUSION

Higher levels of inflammatory cytokines were observed in pediatric patients with pulmonary hypertension secondary to congenital heart disease following cardiopulmonary bypass. Additionally, preoperative elevation in echocardiographic pulmonary artery systolic pressure was associated with increased postoperative inflammatory markers, suggesting a potential correlation with adverse early postoperative clinical outcomes.

Impact of Age and of the Patent Ductus Arteriosus on Pulmonary Hemodynamics in Children with Complete Atrioventricular Septal Defect

Complete atrioventricular septal defect (CAVSD) can lead to the development of pulmonary obstructive vascular disease due to high pulmonary blood flow and pressures. This study aimed to evaluate the changes in pulmonary hemodynamics with aging and with patent ductus arteriosus (PDA) in children with CAVSD. We retrospectively evaluated 137 children (94% with trisomy 21, median age of 195 (25-2963) days, 58.4% female) with CASVD referred to cardiac catheterization from January 2000 to December 2020. Those with associated congenital heart disease, except PDA, had been excluded. They were divided into three age terciles (T1, T2, and T3). Aging was directly associated with higher mean (T1: 34.2 ± 9.1; T2: 37.1 ± 5.8; T3: 42 ± 10.6 mmHg, p < 0.001) and diastolic (T1: 19.4 ± 5.3; T2 21.6 ± 5.0; T3: 26.0 ± 9.5 mmHg, P < 0.001) pulmonary arterial pressures, and with higher pulmonary vascular resistance (T1: 3.24 ± 1.69, T2: 3.47 ± 1.19; T3: 4.49 ± 3.91 Wu.m2, p = 0.023). This resulted in a loss of eligibility for anatomical correction, which became evident only after 300 days of age. PDA was associated with a higher mean (37.2 [35.9; 38.5] vs. 41.3 [37.5; 45.0] mmHg, p = 0.049) and diastolic (21.7 [20.7; 22.6] vs. 26.4 [24.1; 29.0] mmHg, p = 0.001) pulmonary pressure, and resistor-compliance time (0.28 [0.26; 0.29] vs. 0.36 [0.31; 0.40], p = 0.001) after adjusting for age and sex. In children with CAVSD, aging was associated with worsening of pulmonary vascular hemodynamics, particularly when PDA was associated, resulting in loss of eligibility for anatomical correction after 10 months of age as the first surgical option.

Effect of phosphodiesterase type 5 inhibitors on surgical outcome of ventricular septal defect and pulmonary hypertension patients

BACKGROUND

Children with ventricular septal defect (VSD) and large systemic-to-pulmonary shunts eventually develop pulmonary hypertension (PH). The perioperative management of patients with VSD and PH is quite troublesome and still debatable, especially in developing countries where the different management options and standardization of treatment is not available. Oral phosphodiesterase type 5 (PDE-5) inhibitors are good treatment options being widely available, cheap, easy administration and do not require extensive monitoring. The aim of our study was to evaluate the effect of the PDE-5 inhibitors when given orally, early preoperative and continued for 3 months postoperative on controlling postoperative PH with its effect on right ventricle (RV) functions. Fifty-one patients were randomly assigned to either sildenafil or tadalafil, 1 week before and continued for 3 months after corrective surgery. The control group received a placebo.

RESULTS

There was no significant difference in the improvement in the right ventricle systolic pressure (RVSP) between both groups, early in the postoperative period (P = 0.255) and in follow-up (P = 0.259). There was also no significant difference in the changes in mean pulmonary artery pressure (mPAP), postoperatively and on follow-up (P = 0.788 and 0.059, respectively). There was a drop in RV functions in both groups postoperatively which improved on follow-up; however, it was not significant between both groups. The length of intensive care unit (ICU) stay was similar between both groups (P = 0.143).

CONCLUSION

Perioperative administration of PDE-5 inhibitors does not have an impact on the clinical course as regards improvement in pulmonary artery (PA) pressure, ventricular functions and ICU stay.

Preoperative Sildenafil in Pediatric Patients Undergoing Congenital Heart Surgeries: A Systematic Review and Meta-Analysis

Background. Pulmonary hypertension (PH) is a common complication of congenital heart disease (CHD). With early surgical intervention, outcomes have improved over the last two decades. Persistent PH, however, may still occur following surgery. Sildenafil has been shown to be beneficial for postoperative pulmonary hypertensive crises. The role of preoperative sildenafil in controlling postoperative PH is poorly elucidated. This study aimed to evaluate the effect of preoperative sildenafil on pediatric patients undergoing congenital heart surgeries. Methods. A comprehensive literature search was conducted in scientific databases. We included randomized controlled trials which assessed the effect of preoperative sildenafil in pediatric patients with CHD undergoing repair surgeries. Primary outcomes were pre- and postoperative differences in mean pulmonary arterial pressure (mPAP) and mean pulmonary artery/aortic pressure ratio (PA/Ao ratio). Results. Four studies (n = 233) were retained for the final analysis. Dose of sildenafil ranged from .3 to .5 mg/kg every 4-6 hours via oral/nasogastric route, with timing of administration varied from 1 to 2 weeks before surgery. Compared to controls, preoperative sildenafil was associated with greater reduction in postoperative mPAP (MD -5.02; 95% CI [-8.91, -1.13]) and mean PA/Ao ratio (MD -.11; 95% CI [-.17, -.06]). Shorter CPB time, ICU length of stay, and duration of mechanical ventilation were also observed in the sildenafil group. Conclusion. Preoperative sildenafil is beneficial in reducing PAP, thereby reducing the risk of postoperative PH crisis. Further studies are warranted to identify the optimal dosage and timing of administration of sildenafil in CHD patients prior to surgery.

The efficacy of the treat-repair-treat strategy for severe pulmonary arterial hypertension associated with congenital heart disease: a meta-analysis

BACKGROUND

This meta-analysis was conducted to evaluate the efficacy of the treat-repair-treat (TRT) strategy in the treatment of severe pulmonary arterial hypertension with congenital heart disease (PAH-CHD).

METHODS

PubMed, EMBASE, Cochrane and Web of Science online databases were searched by two independent investigators for studies that used the TRT strategy for PAH-CHD, and the retrieved studies were reviewed by a third investigator. The main outcomes were pulmonary artery pressure (PAP), pulmonary vascular resistance (PVR), 6-minute walk distance (6MWD), and transcutaneous oxygen saturation (SpO2). The changes were compared between follow-up and baseline. Stata version 14.0 was used for data analysis. A random-effects model was selected for meta-analysis. Subgroup analysis and meta-regression were used to find the source of heterogeneity.

RESULTS

A total of 335 patients from 9 single-arm studies were included. Meta-analysis showed significant reductions in PAP and PVR and improvements in 6MWD and SpO2 (PAP: SMD -2.73 95% CI -2.97, - 2.50 p = < 0.001; PVR: SMD -1.27 95% CI -1.53, - 1.02 p = < 0.001; 6MWD: SMD 1.88 95% CI 1.49, 2.27 p = < 0.001; SpO2: SMD 3.72 95% CI 3.13, 4.32 p = < 0.001). Subgroup analysis showed that younger patients had better efficacy, and the change in SpO2 was an indication for patient selection. The combined mortality rate was 5% at follow-up.

CONCLUSIONS

In this meta-analysis, we demonstrated that the TRT strategy may have positive effects on haemodynamics and cardiac function in patients with severe PAH-CHD at short-term follow-up. Our analysis suggests that changes in age and SpO2 may be related to patient prognosis.

TRIAL REGISTRATION

The protocol was registered on the PROSPERO website with the registration number CRD42022366552. The relevant registration information can be obtained from the website https://www.crd.york.ac.uk/prospero/#searchadvanced .

Cardiac arrest and cardiopulmonary resuscitation in pediatric patients with cardiac disease: a narrative review

Children with cardiac disease are at a higher risk of cardiac arrest as compared to healthy children. Delivering adequate cardiopulmonary resuscitation (CPR) can be challenging due to anatomic characteristics, risk profiles, and physiologies. We aimed to review the physiological aspects of resuscitation in different cardiac physiologies, summarize the current recommendations, provide un update of current literature, and highlight knowledge gaps to guide research efforts. We specifically reviewed current knowledge on resuscitation strategies for high-risk categories of patients including patients with single-ventricle physiology, right-sided lesions, right ventricle restrictive physiology, left-sided lesions, myocarditis, cardiomyopathy, pulmonary arterial hypertension, and arrhythmias. Cardiac arrest occurs in about 1% of hospitalized children with cardiac disease, and in 5% of those admitted to an intensive care unit. Mortality after cardiac arrest in this population remains high, ranging from 30 to 65%. The neurologic outcome varies widely among studies, with a favorable neurologic outcome at discharge observed in 64%-95% of the survivors. Risk factors for cardiac arrest and associated mortality include younger age, lower weight, prematurity, genetic syndrome, single-ventricle physiology, arrhythmias, pulmonary arterial hypertension, comorbidities, mechanical ventilation preceding cardiac arrest, surgical complexity, higher vasoactive-inotropic score, and factors related to resources and institutional characteristics. Recent data suggest that Extracorporeal membrane oxygenation CPR (ECPR) may be a valid strategy in centers with expertise. Overall, knowledge on resuscitation strategies based on physiology remains limited, with a crucial need for further research in this field. Collaborative and interprofessional studies are highly needed to improve care and outcomes for this high-risk population. What is Known: • Children with cardiac disease are at high risk of cardiac arrest, and cardiopulmonary resuscitation may be challenging due to unique characteristics and different physiologies. • Mortality after cardiac arrest remains high and neurologic outcomes suboptimal. What is New: • We reviewed the unique resuscitation challenges, current knowledge, and recommendations for different cardiac physiologies. • We highlighted knowledge gaps to guide research efforts aimed to improve care and outcomes in this high-risk population.

Evaluation of Portal, Splenic, and Hepatic Vein Flows in Children Undergoing Congenital Heart Surgery

OBJECTIVE

Little is known about changes in portal, splenic, and hepatic vein flow patterns in children undergoing congenital heart surgery. This study aimed to determine the characteristics of portal, splenic, and hepatic vein flow patterns using ultrasonography in children undergoing cardiac surgery.

DESIGN

Single-center, prospective observational study.

SETTING

Tertiary children's hospital, operating room.

PARTICIPANTS

Children undergoing cardiac surgery.

MEASUREMENT AND MAIN RESULTS

The authors obtained ultrasound data from the heart, inferior vena cava, portal, splenic, and hepatic veins before and after surgeries. In the biventricular group, which included children with atrial and ventricular septal defects and pulmonary stenosis (n = 246), the portal pulsatility index decreased from 38.7% to 25.6% (p < 0.001) after surgery. The preoperative portal pulsatility index was significantly higher in patients with pulmonary hypertension (43.3% v 27.4%; p < 0.001). In the single-ventricle group (n = 77), maximum portal vein flow velocities of Fontan patients were significantly lower (13.5 cm/s) compared with that of patients with modified Blalock-Taussig shunt (19.7 cm/s; p = 0.035) or bidirectional cavopulmonary shunt (23.1 cm/s; p < 0.001). The cardiac index was inversely correlated with the portal pulsatility index in the bidirectional cavopulmonary shunt and Fontan circulation. (β = -5.693, r² = 0.473; p = 0.001) The portal pulsatility index was correlated with splenic venous pulsatility and hepatic venous atrial reverse flow velocity in biventricular and single-ventricle groups.

CONCLUSIONS

The characteristics of venous Doppler patterns in the portal, splenic, and hepatic veins differed according to congenital heart disease. Further studies are required to determine the association between splanchnic venous Doppler findings and clinical outcomes in this population.

An Assessment of the Practice of Neuromuscular Blockade and the Association Between Its Prophylactic Use and Outcomes Among Postoperative Pediatric Cardiac Patients

OBJECTIVES

The authors investigated the management of neuromuscular blocking agents (NMBAs) for pediatric patients after cardiac surgery, and compared the outcomes of patients who received prophylactic NMBA (pNMBA) infusions and patients without pNMBA infusions.

DESIGN

A retrospective cohort study.

SETTING

At a tertiary teaching hospital.

PARTICIPANTS

Patients younger than 18, with congenital heart disease, who underwent cardiac surgery.

INTERVENTIONS

Commencement of NMBA infusion in the first 2 hours after surgery MEASUREMENTS AND MAIN RESULTS: The primary endpoint was a composite of one or more of the following major adverse events (MAEs) that occurred within 7 days after surgery: death from any cause, a circulatory collapse that needed cardiopulmonary resuscitation, and requirement for extracorporeal membrane oxygenation. The secondary endpoints included the total duration of mechanical ventilation for the first 30 days after surgery. A total of 566 patients were included in this study. The MAEs occurred in 13 patients (2.3%). An NMBA was commenced within 2 hours after surgery in 207 patients (36.6%). There were significant differences in the incidence of postoperative MAEs between the pNMBA group and the non-pNMBA group (5.3% v 0.6%; p < 0.001). In multivariate regression models, pNMBA infusion was not significantly associated with the incidence of MAEs (odds ratio: 1.79, 95% CI: 0.23-13.93, p = 0.58), but was significantly associated with prolonged mechanical ventilation by 3.85 days (p < 0.001).

CONCLUSIONS

Postoperative prophylactic neuromuscular blockade after cardiac surgery can be associated with prolonged mechanical ventilation, but has no association with MAEs among pediatric patients with congenital heart disease.

Operability of atrial septal defect with borderline pulmonary vascular resistance index: A study in developing country

Background

Pulmonary arterial hypertension secondary to atrial septal defect (ASD) is an important determinant of morbidity and mortality in defect closure. We aimed to compare perioperative outcome between preoperative borderline and low pulmonary vascular resistance index (≥4 WU.m2 and &lt;4 WU.m2, respectively) in surgical closure of secundum atrial septal defect with concomitant pulmonary arterial hypertension.

Methods and results

This was a single-center retrospective cohort study between January 2015 and January 2020. We classified patients with low and borderline PVRI who underwent ASD closure and recorded the perioperative outcomes.

Results

We analyzed a total of 183 patients with atrial septal defect and pulmonary arterial hypertension; 92 patients with borderline PVRI and 91 patients with low PVRI. Borderline pulmonary vascular resistance index was not associated with increased risk of postoperative mortality (p = 0.621; OR0.48, 95% CI 0.04–5.48), but associated with higher risk of overall morbidity in bivariate analysis (p = 0.002; OR3.28, 95% CI 1.5–6.72). Multivariate analysis showed positive association of borderline pulmonary vascular resistance index (p = 0.045; OR2.63, 95% CI 1.02–6.77) and preoperative tricuspid valve gradient ≥64 mmHg (p = 0.034; OR2.77, 95% CI 1.08–7.13) with overall morbidity.

Conclusion

There is no difference in incidence of in-hospital mortality between preoperative borderline and low pulmonary vascular resistance index patients. However, preoperative borderline pulmonary vascular resistance index and tricuspid valve gradient ≥64 mmHg are associated with increased overall morbidity after surgical closure in secundum atrial septal defect patients with pulmonary arterial hypertension.

A systematic review of clinical study evidence for pulmonary vasodilator therapy following surgery with cardiopulmonary bypass in children with CHD

OBJECTIVES

Complications from pulmonary hypertension are one of the leading contributors to morbidity and mortality post-cardiopulmonary bypass surgery in children with CHD. Pulmonary vasodilator therapies are commonly used post-operatively, but the optimal target patient population, therapy choice, timing of therapy initiation, and duration of therapy are not well defined.

METHODS

We used PubMed and EMBASE to identify studies from 2000 to 2020 investigating the use of pulmonary vasodilator therapy post-cardiopulmonary bypass in children aged 0-18 years. To ensure eligibility criteria, studies were systematically reviewed by two independent reviewers.

RESULTS

We identified 26 studies of 42,971 children across four medication classes; 23 were single centre, 14 were prospective, and 11 involved randomisation (four of which employed a placebo-control arm). A disproportionate number of children were from a single retrospective study of 41,872 patients. Definitions varied, but change in pulmonary haemodynamics was the most common primary outcome, used in 14 studies. Six studies had clinical endpoints, with mortality the primary endpoint for two studies. Treatment with inhaled nitric oxide, iloprost, and sildenafil all resulted in improved haemodynamics in specific cohorts of children with post-operative pulmonary hypertension, although improved outcomes were not consistently demonstrated across all treated children. Iloprost may be a cheaper alternative to inhaled nitric oxide with similar haemodynamic response.

CONCLUSION

Studies were predominantly single-centre, a control arm was rarely used in randomised studies, and haemodynamic endpoints varied significantly. Further research is needed to reduce post-operative morbidity and mortality from pulmonary hypertension in children with CHD.

The Outcomes of Total Anomalous Pulmonary Venous Connection in Neonates-10-Year Experience at a Single Center

Background: Recent developments in surgical techniques and hospital care have led to improved outcomes following repair of total anomalous pulmonary venous connection (TAPVC). However, surgical repair of neonatal TAPVC remains associated with a high risk of postoperative mortality and pulmonary venous obstruction (PVO). We conducted this retrospective study to identify risk factors associated with surgical outcomes in the neonatal population.

Methods: A retrospective review was conducted for all 127 neonates who underwent operations for isolated TAPVC from January 2009 to January 2019.

Results: Preoperative PVO occurred in 33 (26.0%) of the 127 patients. Fifty patients (39.4%) required tracheal intubation before the operation. Twenty-three patients (18.1%) underwent emergency surgery. There were 11 (8.7%) early deaths. Significant risk factors were prolonged cardiopulmonary bypass (CPB) time (p = 0.013) and increased postoperative central venous pressure (CVP, p = 0.036). There were 5 (4.3%) late deaths within 1 year of repair. The risk factors for overall death were preoperative acidosis (p = 0.001), prolonged CPB time (p < 0.001) and increased postoperative CVP (p = 0.007). In particular, mortality was significantly higher (p = 0.007) with a postoperative CVP > 8 mmHg. With an increase in use of sutureless techniques (p = 0.001) and decrease in deep hypothermic circulatory arrest (p = 0.009) over the past 5 years, postoperative mortality greatly decreased (21.2%: 6.7%, p = 0.016). Postoperative PVO occurred in 15 patients (11.8%). Risk factors were mixed TAPVC (p = 0.037), preoperative acidosis (p = 0.001) and prolonged CPB time (p = 0.006).

Conclusion: Although postoperative mortality of neonatal TAPVC has dropped to 6.7% over the past 5 years, it is still relatively high. Risk factors for postoperative death include preoperative acidosis, prolonged CPB time and increased postoperative CVP. Mortality was significantly higher for neonates with an average CVP > 8 mmHg 24 h after surgery.

Nitroglycerin inhalation for acute treatment of pulmonary arterial hypertension in children with congenital heart disease

OBJECTIVES

Acute pulmonary hypertension and pulmonary hypertensive crisis may result in adverse clinical outcomes if unsuccessfully treated. Inhaled nitric oxide has long been considered as the standard pharmacotherapy for acute pulmonary hypertension, but lack of feasibility in some settings and evidences challenging its benefits lead to the use of alternative treatment, amongst which is nitroglycerin inhalation. The purpose of this review article is to discuss available data on the use of nitroglycerin inhalation for acute treatment of pulmonary hypertension in children with CHD and its potential benefit in post-operative setting.

DATA SOURCES

Literatures included in this review were acquired by searching in PubMed online database. Keywords used were "Pulmonary Hypertension", "Congenital heart defects", "Pediatrics", "Inhaled nitroglycerin", and its synonyms.

STUDY SELECTION

Title and abstract were screened to select relevant literatures including the three paediatric clinical trials on nitroglycerin inhalation. Critical appraisal of the clinical trials was then done using the University of Oxford Centre of Evidence-Based Medicine Critical Appraisal Tools.

CONCLUSIONS

Paediatric studies showed the benefit of nitroglycerin inhalation in uncorrected cases of CHD during catheterisation procedures. Until recently, there have been no studies conducted in paediatric post-operative CHD cases. Further study is required to provide evidence for inhaled nitroglycerin use in this setting including the appropriate dosing and potential side effects with repeated administration.

Down syndrome and congenital heart disease: perioperative planning and management

Approximately 50% of newborns with Down syndrome have congenital heart disease. Non-cardiac comorbidities may also be present. Many of the principles and strategies of perioperative evaluation and management for patients with congenital heart disease apply to those with Down syndrome. Nevertheless, careful planning for cardiac surgery is required, evaluating for both cardiac and noncardiac disease, with careful consideration of the risk for pulmonary hypertension. In this manuscript, for children with Down syndrome and hemodynamically significant congenital heart disease, we will summarize the epidemiology of heart defects that warrant intervention. We will review perioperative planning for this unique population, including anesthetic considerations, common postoperative issues, nutritional strategies, and discharge planning. Special considerations for single ventricle palliation and heart transplantation evaluation will also be discussed. Overall, the risk of mortality with cardiac surgery in pediatric patients with Down syndrome is no more than the general population, except for those with functional single ventricle heart defects. Underlying comorbidities may contribute to postoperative complications and increased length of stay. A strong understanding of cardiac and non-cardiac considerations in children with Down syndrome will help clinicians optimize perioperative care and long-term outcomes.

Congenital Heart Disease-Associated Pulmonary Hypertension

Presently, with increasing survival of patients with congenital heart disease (CHD), pulmonary arterial hypertension (PAH) associated with CHD is commonly encountered in children and adults. This increased prevalence is seen despite significant advances in early diagnosis and surgical correction of patients with structural CHD. PAH is the cause of significant morbidity and mortality in these patients and comes in many forms. With the increased availability of targeted therapies for PAH, there is hope for improved hemodynamics, exercise capacity, quality of life, and possibly survival for these patients. There may also be opportunities for combined medical and interventional/surgical approaches for some.

Pulmonary Hypertension with Prolonged Patency of the Ductus Arteriosus in Preterm Infants

There continues to be a reluctance to close the patent ductus arteriosus (PDA) in premature infants. The debate on whether the short-term outcomes translate to a difference in long-term benefits remains. This article intends to review the pulmonary vasculature changes that can occur with a chronic hemodynamically significant PDA in a preterm infant. It also explains the rationale and decision-making involved in a diagnostic cardiac catheterization and transcatheter PDA closure in these preterm infants.

Effects of inhaled nitric oxide on haemodynamics and gas exchange in children after having undergone cardiac surgery utilising cardiopulmonary bypass

INTRODUCTION

For CHD patients undergoing corrective surgery utilising cardiopulmonary bypass, post-operative inhaled nitric oxide has been administered to alleviate pulmonary hypertension. We performed a systematic review and meta-analyses to determine the effect of inhaled nitric oxide on haemodynamics, gas exchange, and hospitalisation characteristics in children immediately after cardiopulmonary bypass.

MATERIALS AND METHODS

A systematic review of the literature was performed to identify full-text manuscripts in English. PubMed, EMBASE, and the Cochrane databases were queried. Once manuscripts were identified for inclusion, a list of all the endpoints in each manuscript was created. Endpoints with data present from two or more studies were then kept for pooled analyses. All endpoints included were continuous variables and so mean and standard deviation were utilised as the effect data for comparison.

RESULTS

A total of eight studies were deemed appropriate for inclusion. There were significant differences with decreases in mean pulmonary artery pressure of -6.82 mmHg, left atrial pressure of -1.16 mmHg, arteriovenous oxygen difference of -1.63, arterial carbon dioxide concentration of -2.41 mmHg, mechanical ventilation duration of -8.56 hours, and length of cardiac ICU stay duration of -0.91 days. All significant variables achieved p < 0.001.

CONCLUSION

Inhaled nitric oxide in children immediately after cardiopulmonary bypass decreases mean pulmonary artery pressure significantly and decreases the arterial carbon dioxide concentration significantly without significantly altering other haemodynamic parameters. This results in a statistically shorter duration of mechanical ventilation and cardiac ICU length of stay without altering overall hospital length of stay.

Postoperative Inhaled Nitric Oxide Does Not Decrease Length of Stay in Pediatric Cardiac Surgery Admissions

Pulmonary hypertension is one of the most challenging complications in congenital heart surgery. The purpose of this study was to characterize inhaled nitric oxide administration in children with and without pulmonary hypertension who underwent congenital heart surgery and to describe the effect of nitric oxide administration on admission outcomes. This is a cross-sectional study utilizing data from the Pediatric Health Information System (PHIS) and PHIS + databases from 2004 to 2015. Pediatric patients with a congenital heart disease diagnosis were included and divided into groups with pulmonary hypertension that received and not received inhaled nitric oxide and patients without diagnosis of pulmonary hypertension who received and did not receive inhaled nitric oxide. For all admissions, the following were captured: age of admission, gender, year of admission, length of stay, billed charges, inpatient mortality, the presence of specific congenital malformations of the heart, specific cardiac surgeries, and comorbidities. Comparisons between groups were completed using a Mann-Whitney-U test and Fisher's exact test. Outcomes evaluation was completed using univariate and regression analyses. A total of 40,194 pediatric cardiac surgical admissions without pulmonary hypertension were identified. Of these, 726 (1.8%) received inhaled nitric oxide. Regression analyses demonstrated that inhaled nitric oxide was independently associated with increased length of stay, billed charges, and inpatient mortality. A total of 1678 pediatric cardiac surgical admissions with pulmonary hypertension were identified. Of these, 195 (11.6%) received inhaled nitric oxide. Regression analyses demonstrated that inhaled nitric oxide was independently associated with a significant increase in length of stay and billed charges. There was no statistically significant association between inhaled nitric oxide and decrease mortality. Administration of inhaled nitric oxide after pediatric cardiac surgery increases length of stay and billed charges while not providing improved inpatient mortality. In fact, administration of inhaled nitric oxide was associated with increased mortality in those without pulmonary hypertension while not impacting mortality in any way in those with pulmonary hypertension.

Utilization of inhaled nitric oxide after surgical repair of truncus arteriosus: A multicenter analysis

BACKGROUND

Elevated pulmonary vascular resistance (PVR) is common following repair of truncus arteriosus. Inhaled nitric oxide (iNO) is an effective yet costly therapy that is frequently implemented postoperatively to manage elevated PVR.

OBJECTIVES

We aimed to describe practice patterns of iNO use in a multicenter cohort of patients who underwent repair of truncus arteriosus, a lesion in which recovery is often complicated by elevated PVR. We also sought to identify patient and center factors that were more commonly associated with the use of iNO in the postoperative period.

DESIGN

Retrospective cohort study.

SETTING

15 tertiary care pediatric referral centers.

PATIENTS

All infants who underwent definitive repair of truncus arteriosus without aortic arch obstruction between 2009 and 2016.

INTERVENTIONS

Descriptive statistics were used to demonstrate practice patterns of iNO use. Bivariate comparisons of characteristics of patients who did and did not receive iNO were performed, followed by multivariable mixed logistic regression analysis using backward elimination to identify independent predictors of iNO use.

MAIN RESULTS

We reviewed 216 patients who met inclusion criteria, of which 102 (46%) received iNO in the postoperative period: 69 (68%) had iNO started in the operating room and 33 (32%) had iNO initiated in the ICU. Median duration of iNO use was 4 days (range: 1-21 days). In multivariable mixed logistic regression analysis, use of deep hypothermic circulatory arrest (odds ratio: 3.2; 95% confidence interval: 1.2, 8.4) and center (analyzed as a random effect, p = .02) were independently associated with iNO use.

CONCLUSIONS

In this contemporary multicenter study, nearly half of patients who underwent repair of truncus arteriosus received iNO postoperatively. Use of iNO was more dependent on individual center practice rather than patient characteristics. The study suggests a need for collaborative quality initiatives to determine optimal criteria for utilization of this important but expensive therapy.

Hypoplastic left heart syndrome: From bedside to bench and back

Hypoplastic Left Heart Syndrome (HLHS) is a complex Congenital Heart Disease (CHD) that was almost universally fatal until the advent of the Norwood operation in 1981. Children with HLHS who largely succumbed to the disease within the first year of life, are now surviving to adulthood. However, this survival is associated with multiple comorbidities and HLHS infants have a higher mortality rate as compared to other non-HLHS single ventricle patients. In this review we (a) discuss current clinical challenges associated in the care of HLHS patients, (b) explore the use of systems biology in understanding the molecular framework of this disease, (c) evaluate induced pluripotent stem cells as a translational model to understand molecular mechanisms and manipulate them to improve outcomes, and (d) investigate cell therapy, gene therapy, and tissue engineering as a potential tool to regenerate hypoplastic cardiac structures and improve outcomes.

Pediatric Post–Cardiac Arrest Care: A Scientific Statement From the American Heart Association

Successful resuscitation from cardiac arrest results in a post–cardiac arrest syndrome, which can evolve in the days to weeks after return of sustained circulation. The components of post–cardiac arrest syndrome are brain injury, myocardial dysfunction, systemic ischemia/reperfusion response, and persistent precipitating pathophysiology. Pediatric post–cardiac arrest care focuses on anticipating, identifying, and treating this complex physiology to improve survival and neurological outcomes. This scientific statement on post–cardiac arrest care is the result of a consensus process that included pediatric and adult emergency medicine, critical care, cardiac critical care, cardiology, neurology, and nursing specialists who analyzed the past 20 years of pediatric cardiac arrest, adult cardiac arrest, and pediatric critical illness peer-reviewed published literature. The statement summarizes the epidemiology, pathophysiology, management, and prognostication after return of sustained circulation after cardiac arrest, and it provides consensus on the current evidence supporting elements of pediatric post–cardiac arrest care.

Reverse Remodeling of Pulmonary Arterioles After Pulmonary Artery Banding in Patients ≥ 2 Years Old with Severe Pulmonary Arterial Hypertension and Congenital Heart Disease

The purpose of this study was to evaluate the pathological changes of the pulmonary arterioles in patients ≥ 2 years of age who first underwent a pulmonary artery banding (PAB) procedure, followed by bidirectional Glenn or Fontan according to their specific conditions. This was a prospective study of 15 children diagnosed and treated with PAB at the Department of Cardiothoracic Surgery of Anzhen Hospital between January 2009 and December 2012. The percentage of media area (%MS) of pulmonary arteriole, the percentage of media thickness (%MT), and pulmonary arterial density (APSC) were calculated from lung tissue sections. Pulmonary artery pressure decreased significantly after PAB surgery (P < 0.01). Postoperative mean pulmonary artery pressure declined significantly (P < 0.01), the cardiothoracic ratio was reduced (P < 0.05), and percutaneous oxygen saturation (inhaled air) decreased to 80-85% (P < 0.01). %MT (from 35.1 ± 5.6% to 26.9 ± 4.3%, P < 0.01), %MS (from 51.4 ± 6.7% to 32.2 ± 7.4%, P < 0.01), and APSC (from 108.3 ± 38.5 to 83.6 ± 19.6, P < 0.01) were decreased significantly after PAB. Five patients underwent the bidirectional Glenn procedure and four underwent Fontan. In conclusion, the results suggest that PAB can reduce pulmonary artery pressure and that pulmonary arterial lesions can be reversed after PAB.

Perioperative and Anesthetic Considerations in Truncus Arteriosus

Truncus arteriosus is a congenital cardiac lesion in which failure of embryonic truncal septation results in a single semilunar valve and single arterial trunk providing both pulmonary and systemic circulations. Most patients with this lesion are symptomatic in the neonatal period with cyanosis and/or congestive heart failure and undergo complete repair in the first weeks of life. This review will focus on the anatomy, physiology, and perioperative anesthetic management of patients with truncus arteriosus.

Cardiopulmonary Resuscitation in Infants and Children With Cardiac Disease: A Scientific Statement From the American Heart Association

Cardiac arrest occurs at a higher rate in children with heart disease than in healthy children. Pediatric basic life support and advanced life support guidelines focus on delivering high-quality resuscitation in children with normal hearts. The complexity and variability in pediatric heart disease pose unique challenges during resuscitation. A writing group appointed by the American Heart Association reviewed the literature addressing resuscitation in children with heart disease. MEDLINE and Google Scholar databases were searched from 1966 to 2015, cross-referencing pediatric heart disease with pertinent resuscitation search terms. The American College of Cardiology/American Heart Association classification of recommendations and levels of evidence for practice guidelines were used. The recommendations in this statement concur with the critical components of the 2015 American Heart Association pediatric basic life support and pediatric advanced life support guidelines and are meant to serve as a resuscitation supplement. This statement is meant for caregivers of children with heart disease in the prehospital and in-hospital settings. Understanding the anatomy and physiology of the high-risk pediatric cardiac population will promote early recognition and treatment of decompensation to prevent cardiac arrest, increase survival from cardiac arrest by providing high-quality resuscitations, and improve outcomes with postresuscitation care.

Age is not a good predictor of irreversibility of pulmonary hypertension in congenital cardiac malformations with left-to-right shunt

OBJECTIVE

Congenital cardiac malformations with high pulmonary blood flow and pressure due to left-to-right shunts are usually repaired in early infancy for both the benefits of early relief of heart failure and the fear that the concomitant pulmonary hypertension may become irreversible unless these defects are corrected at an early age. Age, however, has been a poor predictor of irreversibility of pulmonary hypertension in our experience, which is presented here.

DESIGN

A retrospective observational study. We defined "late" as age ≥2 years. We examined clinical, echocardiographic, and hemodynamic data from all patients aged ≥2 years with such malformations referred to us from 2004 untill 2015.

SETTING

Department of Pediatric Cardiology and Cardiac Surgery, University Hospital of Vaud, Lausanne, Switzerland.

PATIENTS

There were 39 patients, aged 2-35 years (median: 5 years), without chromosomal abnormalities. All had malformations amenable to biventricular repair, and all had high systolic right ventricular pressures by echocardiography prior to referral.

INTERVENTIONS

All patients underwent catheterization for assessment of pulmonary hypertension. If this was reversible, surgical correction was offered.

OUTCOME MEASURES

(1) Operability based on reversibility of pulmonary hypertension. (2) When surgery was offered, mortality and evidence of persisting postoperative pulmonary hypertension were examined.

RESULTS

Eighteen patients had no pulmonary hypertension, 5 of variable ages were inoperable due to irreversible pulmonary hypertension, and 16 had reversible pulmonary hypertension. Therefore, 34 patients underwent corrective surgery, with no immediate or late mortality. Pulmonary arterial and right ventricular pressures decreased noticeably in all operated patients. This is sustained to date; they are all asymptomatic with no echocardiographic evidence of pulmonary hypertension at a median follow-up of 7 years (range 2-13 years).

CONCLUSIONS

Pulmonary hypertension may still be reversible in many surprisingly old patients with left-to-right shunt lesions, who may therefore still be operable.

Effects of glucocorticoids on serum amino acid levels during cardiac surgery in children

BACKGROUND AND AIMS

Children undergoing cardiac surgery with cardio pulmonary bypass often receive glucocorticoids to reduce the systemic inflammatory response. Glucocorticoids stimulate protein breakdown and increase amino acid availability. We studied whether glucocorticoid treatment influences the availability of amino acids, specifically those involved in the nitric oxide pathway.

METHODS

We prospectively studied 49 children with congenital heart disease undergoing cardiac surgery. Serum cortisol and amino acid levels were measured in arterial blood sampled before surgery (t = -5 min), directly after surgery (t = 0 h) and at t = 12 h and t = 24 h after surgery. Serum cortisol and amino acid levels were compared between children who had received glucocorticoids (G+) and children who had not (G-).

RESULTS

Of 49 patients included ((49% male, age 1.7 (0.5-8.7) y)), 33 (67%) received glucocorticoids. Baseline characteristics were not different between groups, except a higher weighted inotropic score in the G+ group. At t = 0 h, serum cortisol levels in the G+ group were significantly higher than in the G- group (7218 vs. 660 nmol/L; (p < 0.05)), but not different at the other time points. The levels of plasma amino acids had dropped after surgery. Compared to the G- group, in the G+ group the total amount of amino acids was significantly higher at t = 12 and t = 24; citrulline levels were higher at t = 12 and t = 24; and glutamine and arginine levels were higher at t = 12.

CONCLUSIONS

Glucocorticoid treatment during cardiac surgery in children preserves serum amino acid levels post-surgery. The preservation of glutamine, citrulline and arginine levels might have a beneficial effect on the related NO metabolism.

Relation of Cytokine Profile to Clinical and Hemodynamic Features in Young Patients With Congenital Heart Disease and Pulmonary Hypertension

In congenital heart disease, severity of pulmonary hypertension and operability is defined by noninvasive parameters (clinical history, physical examination, and echocardiography) and sometimes, cardiac catheterization. We investigated how circulating levels of inflammatory mediators correlate with such parameters in a young pediatric population (age, 2.0 months to 3.1 years) and the effects of preoperative pulmonary vasodilator therapy with sildenafil. Cytokines were analyzed in serum using chemiluminescence signals. In the whole patient group (n = 47), interleukin 17E, a Th2 immune response mediator increased with increasing age, considered as a parameter of disease severity (R² = 0.24, p <0.001), whereas the angiogenic chemokine growth-regulated oncogene alpha decreased (R² = 0.21, p = 0.001). Macrophage migration inhibitory factor chemokine was greater in subjects with elevated pulmonary vascular resistance (n = 16, p = 0.022), whereas regulated on activation, normal T cell expressed and secreted chemokine was greater in subjects with pulmonary congestion due to increased pulmonary blood flow (n = 31, p = 0.037). The observations were the same for the specific subpopulation of patients with Down syndrome (p = 0.009 and p = 0.012 for migration inhibitory factor and regulated on activation, normal T cell expressed and secreted in the respective subgroups). Sildenafil administration to patients with elevated pulmonary vascular resistance resulted in improvement of pulmonary blood flow (p = 0.012) and systemic oxygen saturation (p = 0.010), with a decrease in serum interleukin 6 (p = 0.027) and soluble ICAM-1 (p = 0.011). In conclusion, levels of circulating inflammatory molecules seem to correlate with disease severity in this population, with potential pathophysiological and therapeutic implications.

Pulmonary Hypertension

OBJECTIVES

To review the clinical classification, diagnosis, and pathophysiology of pulmonary hypertension in children, emphasizing the role of right ventricular function, ventricular interaction, and congenital heart disease in the evolution and progression of disease, as well as management strategies and therapeutic options.

DATA SOURCE

MEDLINE, PubMed.

CONCLUSIONS

Critically ill children with pulmonary hypertension associated with congenital heart disease are a high-risk population. Congenital cardiac defects resulting in either increased pulmonary blood flow or impaired pulmonary venous drainage predispose patients to developing structural and functional aberrations of the pulmonary vasculature. Mortality from pulmonary hypertension is most directly related to right ventricular failure.

Utilizing the PCICS Nursing Guidelines in Managing the CICU Patient

The Pediatric Cardiac Intensive Care Society (PCICS) Nursing Guidelines were developed to provide an evidence-based resource for bedside cardiac intensive care unit nursing care. Guideline topics include postoperative care, hemodynamic monitoring, arrhythmia management, and nutrition. These evidence-based care guidelines were presented at the 10th International Meeting of PCICS and have been utilized in the preparation of this article. They can be accessed at http://www.pcics.org/resources/pediatric-neonatal/. Utilization of these guidelines in practice is illustrated for single ventricle stage 1 palliation, Fontan operation, truncus arteriosus, and atrioventricular septal defect.

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.

Association of aortic stiffness to brain natriuretic peptide in children before and after device closure of patent ductus arteriosus

OBJECTIVES

We evaluated the influence of device closure for patent ductus arteriosus (PDA) on the aortic stiffness index (ASI) and brain natriuretic peptide (BNP) and their association with cardiac function.

PATIENTS AND METHODS

ASI and echocardiography assessment before and after treatment (16 ± 9 months) in 48 children with PDA (mean age 10 ± 4.5) and 52 control children (mean age 9.7 ± 4.6). BNP level was measured pre-closure for all children, and was measured six months after closure only for children with PDA.

RESULTS

ASI was higher in PDA patients than in controls (P < 0.001). ASI correlated with age (P < 0.05), LVEF% (P < 0.01), E/E' (<0.03), pulmonary artery pressure (P < 0.001), and BNP (P < 0.001). ASI and BNP significantly decreased after closure (P < 0.001). ASI and BNP were independent predictors for post-closure systolic dysfunction (P < 0.001and <0.005, respectively). Receiver operating curve (ROC) analysis showed that ASI ⩾ 13.5, BNP level ⩾75 pg/ml and basal mean pulmonary artery pressure (PAP) ⩾ 23 were powerful predictors for post-closure systolic function.

CONCLUSION

ASI is significantly associated with BNP and basal PAP in children with PDA. After device closure, aortic distensibility improved significantly and was associated with significant improvement in both systolic and diastolic functions. ASI can be used for monitoring the course of patients with PDA, and may give opportunities for early intervention.

Perioperative pharmacological management of pulmonary hypertensive crisis during congenital heart surgery

Pulmonary hypertensive crisis is an important cause of morbidity and mortality in patients with pulmonary arterial hypertension secondary to congenital heart disease (PAH-CHD) who require cardiac surgery. At present, prevention and management of perioperative pulmonary hypertensive crisis is aimed at optimizing cardiopulmonary interactions by targeting prostacyclin, endothelin, and nitric oxide signaling pathways within the pulmonary circulation with various pharmacological agents. This review is aimed at familiarizing the practitioner with the current pharmacological treatment for dealing with perioperative pulmonary hypertensive crisis in PAH-CHD patients. Given the life-threatening complications associated with pulmonary hypertensive crisis, proper perioperative planning can help anticipate cardiopulmonary complications and optimize surgical outcomes in this patient population.

[The predictive value of plasma B-type natriuretic peptide levels on outcome in children with pulmonary hypertension undergoing congenital heart surgery]

BACKGROUND AND OBJECTIVES

In children undergoing congenital heart surgery, plasma brain natriuretic peptide levels may have a role in development of low cardiac output syndrome that is defined as a combination of clinical findings and interventions to augment cardiac output in children with pulmonary hypertension.

METHODS

In a prospective observational study, fifty-one children undergoing congenital heart surgery with preoperative echocardiographic study showing pulmonary hypertension were enrolled. The plasma brain natriuretic peptide levels were collected before operation, 12, 24 and 48h after operation. The patients enrolled into the study were divided into two groups depending on: (1) Development of LCOS which is defined as a combination of clinical findings or interventions to augment cardiac output postoperatively; (2) Determination of preoperative brain natriuretic peptide cut-off value by receiver operating curve analysis for low cardiac output syndrome. The secondary end points were: (1) duration of mechanical ventilation ≥72h, (2) intensive care unit stay >7days, and (3) mortality.

RESULTS

The differences in preoperative and postoperative brain natriuretic peptide levels of patients with or without low cardiac output syndrome (n=35, n=16, respectively) showed significant differences in repeated measurement time points (p=0.0001). The preoperative brain natriuretic peptide cut-off value of 125.5pgmL-1 was found to have the highest sensitivity of 88.9% and specificity of 96.9% in predicting low cardiac output syndrome in patients with pulmonary hypertension. A good correlation was found between preoperative plasma brain natriuretic peptide level and duration of mechanical ventilation (r=0.67, p=0.0001).

CONCLUSIONS

In patients with pulmonary hypertension undergoing congenital heart surgery, 91% of patients with preoperative plasma brain natriuretic peptide levels above 125.5pgmL-1 are at risk of developing low cardiac output syndrome which is an important postoperative outcome.

Inhaled nitric oxide for the postoperative management of pulmonary hypertension in infants and children with congenital heart disease

BACKGROUND

Nitric oxide (NO) is a prevalent molecule in humans that is responsible for many physiologic activities including pulmonary vasodilation. An exogenous, inhaled form (iNO) exists that mimics this action without affecting systemic blood pressure. This therapy has been implemented in the treatment of pulmonary hypertension. This review examines the efficacy of iNO in the postoperative management of infants and children with congenital heart disease (CHD). The original review was published in 2005, updated in 2008 and again in 2014.

OBJECTIVES

To compare the effects of postoperative administration of iNO versus placebo or conventional management, or both, on infants and children with CHD and pulmonary hypertension. The primary outcome was mortality. Secondary outcomes included length of hospital stay; neurodevelopmental disability; number of pulmonary hypertensive crises (PHTC); changes in mean pulmonary arterial pressure (MPAP), mean arterial pressure (MAP), and heart rate (HR); changes in oxygenation measured as the ratio of arterial oxygen tension (PaO2) to fraction of inspired oxygen (FiO2); and measurement of maximum methaemoglobin level as a marker of toxicity.

SEARCH METHODS

In this updated version we extended the CENTRAL search to 2013, Issue 12 of The Cochrane Library, and MEDLINE and EMBASE through to 1 December 2013. The original search was performed in July 2004 and again in November 2007. We included abstracts and all languages.

SELECTION CRITERIA

We included randomized and quasi-randomized controlled trials comparing iNO with placebo or conventional management, or both. Trials included only children with CHD requiring surgery complicated by pulmonary hypertension.

DATA COLLECTION AND ANALYSIS

Two authors extracted data. Data were collected on mortality; number of PHTC; changes in MPAP, MAP, HR, and PaO2:FiO2; and maximum methaemoglobin level. Data on long-term mortality, neurodevelopmental disability, and length of hospital stay were unavailable. We performed subgroup analysis by method of control (placebo or conventional management).

MAIN RESULTS

We reran the searches to December 2013 and identified three new studies. These three studies did not fulfil our inclusion criteria. Therefore, no new studies were included in this updated review. In total four randomized trials involving 210 participants were included in this review. We observed no differences in mortality (OR 1.67, 95% CI 0.38 to 7.30; P = 0.50); PHTC (OR 0.80, 95% CI 0.15 to 4.18; P = 0.79); changes in MPAP (treatment effect -2.94 mm Hg, 95% CI -9.28 to 3.40; P = 0.36), MAP (treatment effect -3.55 mm Hg, 95% CI -11.86 to 4.76; P = 0.40), HR (treatment effect 0.02 bpm, 95% CI -8.13 to 8.18; P = 1.00), or PaO2:FiO2 (mean difference 17.18, 95% CI -28.21 to 62.57; P = 0.46). There was a significant increase in the methaemoglobin level (mean difference 0.30%, 95% CI 0.24 to 0.36; P < 0.00001) in patients treated with iNO, although levels did not reach toxicity levels. Data from long-term mortality, neurodevelopmental disability, and length of stay were not available. Two trials had a low risk of bias. Very low quality of the evidence was observed considering grading of the outcomes.

AUTHORS' CONCLUSIONS

We observed no differences with the use of iNO in the outcomes reviewed. No data were available for several clinical outcomes including long-term mortality and neurodevelopmental outcome. We found it difficult to draw valid conclusions given concerns regarding methodologic quality, sample size, and heterogeneity.

The anesthetic management of children with pulmonary hypertension in the cardiac catheterization laboratory

Children need cardiac catheterization to establish the diagnosis and monitor the response to treatment when undergoing drug therapy for the treatment of pulmonary arterial hypertension (PAH). Children with PAH receiving general anesthesia for cardiac catheterization procedures are at significantly increased risk of perioperative complications in comparison with other children. The most acute life-threatening complication is a pulmonary hypertensive crisis. It is essential that the anesthesiologist caring for these children understands the pathophysiology of the disease, how anesthetic medications may affect the patient's hemodynamics, and how to manage an acute pulmonary hypertensive crisis.

Modified single-patch compared with two-patch repair of complete atrioventricular septal defect

BACKGROUND

We compared the outcomes of modified single-patch and two-patch surgical repair of complete atrioventricular septal defect (CAVSD) on left ventricular outflow tract (LVOT) diameter and on left atrioventricular valve (LAVV) coaptation.

METHODS

We reviewed retrospectively postoperative 2-dimensional echocardiograms of all CAVSD patients who underwent modified single-patch or two-patch repair between 2005 and 2011. We measured the leaflet coaptation length of the LAVV in the apical four-chamber view. The LVOT was measured in the long axis view.

RESULTS

Fifty-one patients underwent CAVSD repair at a median age of 4 months (range, 1 to 9 months) (single-patch, n=29; two-patch, n=22). The images from 46 echocardiograms were adequate for analysis. Modified single-patch repair required significantly shorter bypass time (102.0±33.6 vs 152.9±39.5 minutes, p<0.001) and ischemic time (69.0±21.7 vs 106.9±29.7 minutes, p<0.001) than did two-patch repair. The indexed coaptation length of the septal and lateral leaflets was not different between single-patch and two-patch (3.1±2.3 vs 4.1±3.1 mm/m2, p=0.25; 2.3±2.3 vs 3.3±3.0 mm/m2, p=0.21). Indexed LVOT diameter was not different in the two groups (26.1±5.2 vs 28.5±7.1 mm/m2, p=0.22). There was no hospital or late death during the median follow-up time of 35 months (range, 1 to 69 months). Five patients underwent reoperation after single-patch repair (3 with residual ventricular septal defect [VSD] and LAVV regurgitation, 1 with residual VSD, 1 with pacemaker implantation). After the two-patch repair, 1 patient required reoperation for a residual VSD and right atrioventricular valve regurgitation (p=0.22).

CONCLUSIONS

The modified single-patch repair was performed with significantly shorter bypass time and myocardial ischemic time. The postoperative LVOT diameter and LAVV leaflet coaptation length were not significantly different between techniques.

Perioperative sildenafil therapy for pulmonary hypertension in infants undergoing congenital cardiac defect closure

OBJECTIVES

Pulmonary hypertension in paediatric patients with ventricular septal defect remains one of the most important determinants of perioperative morbidity and mortality. Sildenafil is an oral, well-tolerated pulmonary vasodilator with few drug interactions. We studied the effect of oral sildenafil, when given before and after surgical closure compared with starting it postoperatively, on the pulmonary artery pressure and patients' outcome.

METHODS

We enrolled 101 infants with large ventricular septal defects who had moderate-to-severe pulmonary hypertension scheduled for surgical closure. They were randomly assigned to the sildenafil group (n = 51, mean age 10 months and mean weight 6.5 kg), in which oral sildenafil was started 2 weeks before surgery to be continued postoperatively, and to the control group (n = 50, mean age 11 months and mean weight 7.3 kg), in which sildenafil was started only postoperatively. It was started at 0.5 mg/kg and increased gradually to a maximum dose of 2 mg/kg in both groups.

RESULTS

Overall hospital mortality was 4.9%. Mean pulmonary artery pressure decreased significantly at all time points of recording in both groups (P < 0.0001). In the sildenafil group, it decreased preoperatively after sildenafil administration from 75.4 to 59.4 mmHg and postoperatively from 50.4 mmHg immediate post-cardiopulmonary bypass to reach 44.2 mmHg before discharge. In the control group, it decreased from 74.6 mmHg to 51 mmHg immediate post-cardiopulmonary bypass to reach 42.7 mmHg before discharge. No adverse effects have been recorded. Although there was no difference in the duration of mechanical ventilation and hospital stay between the two groups, intensive care unit stay was significantly shorter in the sildenafil group. Dobutamine doses were significantly higher in the sildenafil group; however, milrinone and epinephrine have been used more significantly in the control group.

CONCLUSIONS

The low cost, the oral availability and the good tolerability of sildenafil make it a suitable and simple alternative therapy for secondary pulmonary hypertension including persistent postoperative pulmonary hypertension associated with ventricular septal defect in resource limited places. However, starting sildenafil early before surgery does not add a great benefit in terms of improving postoperative pulmonary hypertension or patients' outcome.

Do preoperative haemodynamic data and reactivity test predict the postoperative reversibility of pulmonary arterial hypertension in patients with large ventricular septal defect and borderline operability?

BACKGROUND

Decisions to operate on patients with shunt lesions presenting late with severe pulmonary arterial hypertension (PAH) and borderline operability are often not based on precise cut off values of haemodynamic data owing to paucity of studies.

OBJECTIVE

To assess the reliability of the preoperative haemodynamic data and reactivity test in predicting the postoperative reversibility of PAH in patients with isolated large ventricular septal defects (VSDs) and borderline operability.

PATIENTS AND METHOD

Between 2004 and 2010, 30 patients underwent VSD closure surgically; no early deaths occurred. Twenty-six patients were followed up regularly (mean 39.6±16 months) and one late postoperative death occurred. Fourteen patients who had been followed up for at least 1 year postoperatively underwent cardiac catheterisation.

RESULTS

There were 3 responders (asymptomatic patients with pulmonary vascular resistance (PVR) index <3 WU.m(2)) and 12 non-responders. The following were lower among responders: mean age at surgery (3.2±0.42 vs 11.55±3.29 years, p=0.227), mean baseline PVR index (3.69±0.8 vs 10.57±9.1, p=0.204), average resistance ratio (RR=0.25±0.01 vs 0.59±0.25, p=0.049) and ratio of pulmonary and systemic mean pressures (PAm:SAm ratio) (0.70±0.009 vs 0.87±0.118, p=0.003).

CONCLUSIONS

Preoperative 'base line' PAm:SAm and RR appear to be better predictors of postoperative outcome than other baseline parameters. Preoperative reactivity test had no significant role in predicting postoperative reversibility of PAH at mid-term.

Epidemiology of nosocomial infections and mortality following congenital cardiac surgery in Cairo University, Egypt

BACKGROUND

Nosocomial infections (NI) have been associated with significant morbidity and attributed mortality, as well as increased healthcare costs. Relatively few data on congenital cardiac surgical ICU NI have been reported from developing countries. Little is known about the epidemiology of NI following congenital cardiac surgery in Egypt. The aims of the present study were: (a) to estimate the incidence rate and types of NI among children admitted to Pediatric Surgical Cardiac ICU in Cairo University Children's Hospital (Egypt) and (b) to estimate the mortality rate related to congenital cardiac surgery and identify its contributing risk factors.

PARTICIPANTS AND METHODS

A follow-up study in the period between 1 January 2009 and 1 January 2010 included all patients admitted to the Pediatric Surgical Cardiac ICU in Cairo University, Abo El Reesh Children's Specialized Hospital (Egypt). Data were collected for each patient during the preoperative, intraoperative, and postoperative periods. Certain infection control procedures were carried out in certain months.

RESULTS

Of 175 patients, NI were identified in 119 (68%). Poor hand hygiene was associated with increased NI in certain months of the study duration. NI were significantly higher at a younger age [median 9 (5-30) months, P<0.03]. Mortality was found in 54 patients, that is, 31% of the study population. Mortality was significantly observed with younger age, higher complexity score for congenital cardiac lesions, prolonged cardiopulmonary bypass and ischemic times, NI, prolonged mechanical ventilation, prolonged central line insertion, and the use of total parenteral nutrition. Mortality among the NI patients was found in 44 of 119 (37%). On carrying out a multivariate analysis, Acute Physiology and Chronic Health Evaluation II score [P<0.001, odds ratio (OR) 1.13, 95% confidence interval (CI) 1-1.2], age (P<0.001, OR 0.3, 95% CI 0.2-0.4), and prolonged duration of mechanical ventilation (P<0.03, OR 2.8, 95% CI 1.1-7.2) were identified as risk factors of mortality.

CONCLUSION AND RECOMMENDATIONS

NI rate and subsequent mortality were high among cases followed up during the period from 1 January 2009 to 1 January 2010 in the University Children's Hospital (Cairo, Egypt). Early surgical interference, enforcement of proper infection control practices, especially hand hygiene, can reduce NI and trials for early extubation from mechanical ventilation might improve outcome following congenital cardiac surgery in pediatrics.

Endothelial nitric oxide synthase gene polymorphism (Glu298Asp) and acute pulmonary hypertension post cardiopulmonary bypass in children with congenital cardiac diseases

BACKGROUND

Intra-cardiac repair of congenital cardiac diseases in children with left-right shunt is often associated with acute elevation of pulmonary artery pressure following cardiopulmonary bypass. We studied the correlation between the Glu298Asp polymorphism of the endothelial nitric oxide synthase gene and pulmonary hypertension in children with congenital cardiac diseases.

METHODS AND RESULTS

A total of 80 children with congenital cardiac diseases at a median age of 3.8 years, ranged 0.1-36.2 years, and 136 controls were enrolled. Most patients presented with significant left-to-right shunt - pulmonary-to-systemic blood flow of 2.8, with a range from 0.6 to 7.5. In all, 40 out of 80 children showed pulmonary hypertension with mean pressure of 42, ranged 26-82, millimetres of mercury. Thirty-one out of 40 children underwent intra-cardiac repair and 15 out of 31 operated patients were found to have an acute elevation of pulmonary artery pressure after cardiopulmonary bypass. The Glu298Asp polymorphism was identified using polymerase chain reaction and restriction fragment length polymorphism. Both in patients and in controls, the genotype distribution corresponded to the Hardy-Weinberg equilibrium. The gene frequency for Glu298Glu, Glu298Asp and Asp298Asp was not different in the control group compared to the patients (Armitage trend test: p = 0.37). The endothelial nitric oxide synthase polymorphism was related to acute post-operative elevation of pulmonary artery pressure (genotypic frequency 53.3 versus 25%; Armitage trend test: p = 0.038). In addition, the allelic frequency of the Glu298Asp was related to post-operative pulmonary hypertension (Fischer's exact test: p = 0.048). The positive predictive value was 71.43%.

CONCLUSION

Patients with left-to-right shunt are more likely to develop acute elevation of pulmonary artery pressure after cardiopulmonary bypass when presenting with the Glu298Asp polymorphism of the gene endothelial nitric oxide synthase. This could be used as a genetic marker for the predisposition for the development of pulmonary hypertension after intra-cardiac repair.

Pulmonary hypertension in congenital shunts

Pulmonary arterial hypertension frequently arises in patients with congenital heart disease. The vast majority present with congenital cardiac shunts. Initially these may manifest as left-to-right (i.e. systemic-to-pulmonary) shunts. The natural history of disease progression involves vascular remodeling and dysfunction that lead to increased pulmonary vascular resistance and, finally, to the development of Eisenmenger's syndrome, which is the most advanced form. The anatomical, pathological and structural abnormalities occurring in the pulmonary circulation of these patients are, to some extent, similar to those observed in other forms of pulmonary arterial hypertension. This understanding has recently led to significant changes in the management of Eisenmenger's syndrome, with the introduction of treatment specifically targeting pulmonary vascular disease. Early closure of the cardiac shunt remains the best way of preventing pulmonary vascular lesions. However, it is still not clear which preoperative parameters predict safe and successful repair, though hemodynamic evaluation is still routinely used for assessment. Postoperative pulmonary hypertension, both in the immediate period after surgical repair and during long-term follow-up, remains a real therapeutic challenge. The clinical situation of a single ventricle with Fontan circulation also presents difficulties when pulmonary vascular lesions are present. This article reviews pulmonary hypertension associated with congenital shunts and discusses a number of the specific problems encountered.

Functional interaction between Foxd3 and Pax3 in cardiac neural crest development

The transcription factors Foxd3 and Pax3 are important early regulators of neural crest (NC) progenitor cell properties. Homozygous mutations of Pax3 or a homozygous NC-specific deletion of Foxd3 cause marked defects in most NC derivatives, but neither loss of both Foxd3 alleles nor loss of one Pax3 allele alone greatly affects overall development of cardiac NC derivatives. In contrast, compound mutant embryos homozygous for a NC-specific Foxd3 mutation and heterozygous for Pax3 have fully penetrant persistent truncus arteriosus, severe thymus hypoplasia, and midgestation lethality. Foxd3; Pax3 compound mutant embryos have increased cell death in the neural folds and a drastic early reduction of NC cells, with an almost complete absence of NC caudal to the first pharyngeal arch. The genetic interaction between these genes implicates gene dosage-sensitive roles for Foxd3 and Pax3 in cardiac NC progenitors. Foxd3 and Pax3 act together to affect survival and maintenance of cardiac NC progenitors, and loss of these progenitors catastrophically affects key aspects of later cardiovascular development.

Intravenous sildenafil for postoperative pulmonary hypertension in children with congenital heart disease

Purpose

To evaluate the efficacy and safety of intravenous sildenafil for immediate postoperative pulmonary hypertension (PH) in pediatric patients undergoing congenital heart surgery.

Methods

A double-blind, multicenter, placebo-controlled, dose-ranging, parallel-group trial was conducted. Patients were randomized to one of three doses of intravenous sildenafil, or placebo, for a minimum of 24 h.

Results

The study was heavily underpowered. Whereas enrollment of 228 patients (57 per treatment arm) was required to achieve the sample size estimate to detect difference between arms, the sponsor terminated the study after 15 months owing to slow patient accrual. Seventeen patients (median age 5 months) experiencing postoperative PH were randomized and treated, five with placebo and four each with low-, medium-, and high-dose sildenafil. In the first 24 h, 40% of placebo and 17% of sildenafil patients required additional therapy (p = 0.330). Median time to extubation (3 versus 8 days, p = 0.023) and intensive care unit stay (6 versus 15 days, p = 0.008) were shorter for sildenafil patients. Mean ± standard deviation systolic pulmonary artery pressure was reduced with sildenafil (46 ± 11 to 35 ± 6 mmHg, p = 0.027 versus placebo). No adverse events or systemic hypotension were attributed to sildenafil.

Conclusion

Intravenous sildenafil reduced pulmonary artery pressure and shortened time to extubation and intensive care unit stay in children with postoperative PH.

Electronic supplementary material

The online version of this article (doi:10.1007/s00134-010-2065-4) contains supplementary material, which is available to authorized users.