Use of Oxandrolone to Promote Growth in Neonates following Surgery for Complex Congenital Heart Disease: An Open-Label Pilot Trial

Multicenter Clinical Research in Congenital Heart Disease: Leveraging Research Networks to Investigate Important Unanswered Questions

Congenital heart disease (CHD) is the most common birth defect in the United States. Neonates with CHD are often cared for by neonatologists in addition to cardiologists. However, there is a paucity of rigorous evidence and limited clinical trials regarding the management of neonates with CHD. In this review, we will describe some of the challenges of research in this field. The Pediatric Heart Network serves as an example of how a research network can effectively overcome barriers to conduct and execute well-designed multicenter studies.

Feeding challenges in the newborn with congenital heart disease

PURPOSE OF REVIEW

Feeding challenges and growth failure are lifelong issues for infants with congenital heart disease. The purpose of this review is to summarize the literature on the topic from North America.

RECENT FINDINGS

Despite recognition of feeding challenges and ongoing national collaboration, >50% of infants with univentricular physiology continue to require supplemental tube feeds at the time of discharge from neonatal surgery. Preoperative feeding is now commonly used in prostaglandin dependent neonates with congenital heart disease. The value of a structured nutritional program with establishment of best practices in nutrition is well recognized in the current era. Despite implementation of these best practices, neonates undergoing cardiac surgery continue to struggle with weight gain prior to discharge. This suggests that there is more to growth than provision of adequate nutrition alone.

SUMMARY

The National Pediatric Cardiology Quality Improvement Collaborative continues to play a major role in optimizing nutrition in infants with congenital heart disease. This among other registries underscores the importance of collaboration in improving overall outcomes for children with congenital heart disease. Nurses should be encouraged to lead both clinical and research efforts to overcome feeding challenges encountered by these children.

Early high-energy feeding in infants following cardiac surgery: a randomized controlled trial

BACKGROUND

Effective nutrition programs are beneficial for nutritional recovery in infants. Few studies have focused on the effect of early high-energy feeding after open heart surgery. This study sought to assess the effects of early high-energy feeding in infants after congenital heart surgery.

METHODS

Patients at a tertiary pediatric cardiology center who underwent open heart surgery between July 2016 and July 2018 were recruited and randomly allocated to 1 of the following 2 groups: (I) the intervention group (postoperative early high-energy feeding; n=124); and (II) the control group (no intervention; n=120).The primary endpoints of average energy delivery and growth Z-scores [i.e., weight-for-height Z-score (WHZ), weight-for-age Z-score (WAZ), and height-for-age Z-score (HAZ)] were recorded preoperatively, during the intensive care unit (ICU) stay, at discharge, and at 1 and 3 months postoperatively. The secondary endpoints of malnutrition recovery, ventilator support time, infection rate, and cardiac ICU (CICU) stay were also recorded.

RESULTS

A total of 244 infants were included in the study. There were no significant differences in the baseline features between the 2 groups. The intervention group received higher calories on average than the control group (44.5 vs. 34.7; P<0.001). At discharge from the ICU, the WHZ (-2.29 vs. -2.76; P<0.001) and WAZ (-3.08 vs. -3.43; P=0.005) of patients in the intervention group were higher than those of patients in the control group. Ventilator support time (P=0.004), CICU stay (P=0.045), and infection rate (P=0.001) were significantly lower in the intervention group than the control group. At 3 months post-surgery, the intervention group exhibited a higher malnutrition recovery rate than the control group (19.4% vs. 6.5%; P=0.002).

CONCLUSIONS

The administration of early high-energy feeding to infants after congenital heart surgery is associated with improved growth, reduced CICU stay, decreased ventilator support time, and reduced postoperative infection rates.

TRIAL REGISTRATION

ClinicalTrials NCT04609358.

Hypoplastic left heart syndrome (HLHS): molecular pathogenesis and emerging drug targets for cardiac repair and regeneration

INTRODUCTION

Hypoplastic left heart syndrome (HLHS) is a severe developmental defect characterized by the underdevelopment of the left ventricle along with aortic and valvular defects. Multiple palliative surgeries are required for survival. Emerging studies have identified potential mechanisms for the disease onset, including genetic and hemodynamic causes. Genetic variants associated with HLHS include transcription factors, chromatin remodelers, structural proteins, and signaling proteins necessary for normal heart development. Nonetheless, current therapies are being tested clinically and have shown promising results at improving cardiac function in patients who have undergone palliative surgeries.

AREAS COVERED

We searched PubMed and clinicaltrials.gov to review most of the mechanistic research and clinical trials involving HLHS. This review discusses the anatomy and pathology of HLHS hearts. We highlight some of the identified genetic variants that underly the molecular pathogenesis of HLHS. Additionally, we discuss some of the emerging therapies and their limitations for HLHS.

EXPERT OPINION

While HLHS etiology is largely obscure, palliative therapies remain the most viable option for the patients. It is necessary to generate animal and stem cell models to understand the underlying genetic causes directly leading to HLHS and facilitate the use of gene-based therapies to improve cardiac development and regeneration.

Poor Weight Recovery Between Stage 1 Palliation and Hospital Discharge for Infants with Single Ventricle Physiology: An Analysis of the National Pediatric Cardiology Quality Improvement Collaborative Phase II Dataset

OBJECTIVE

To investigate change in weight-for-age z-scores (WAZ) and risk factors for impaired weight gain between stage 1 palliation (S1P) for single ventricle physiology and discharge.

STUDY DESIGN

This was a secondary analysis of the National Pediatric Cardiology Quality Improvement Collaborative Phase II database. The primary outcome was change in WAZ between S1P and discharge. Risk factors were selected using multivariable mixed effects regression constructed by step-wise model selection, with adjustment for WAZ at S1P and a random effect for center.

RESULTS

Of 730 infants who were discharged after S1P, WAZ decreased in 98.6% (-1.5 ± 0.7). WAZ at discharge was <-1 but >-2 (at risk) in 40% and <-2 (failure to thrive) in 35% of participants. Males, higher WAZ at S1P, non-S1P procedures (mostly noncardiac), increased length of stay, necrotizing enterocolitis, and angiotensin-converting enzyme inhibitor use at discharge were associated with a greater decrease in WAZ. Preoperative enteral feeding and respiratory medications were associated with a lesser decrease in the WAZ.

CONCLUSIONS

Nearly all infants lose weight after S1P with little recovery by hospital discharge. At discharge, three-quarters of the infants in the cohort were at risk for impaired weight gain or had failure to thrive. Most risk factors associated with change in WAZ were unmodifiable or surrogates of disease severity. Novel interventions are needed to minimize the early catabolic effects and promote anabolic recovery after S1P.

Is treatment of hypogonadism safe for men after a solid organ transplant? Results from a retrospective controlled cohort study

Male solid organ transplant patients are at increased risk of hypogonadism and the safety of treating these patients for hypogonadism is unknown. We sought to evaluate the safety of treating hypogonadism in the solid organ transplant recipient. To accomplish this, we performed a retrospective review between 2009 and 2017 of patients treated at a single academic urology clinic. Men who underwent a solid organ transplant with a diagnosis of hypogonadism (Testosterone <350 ng/dl) were included. In total, 87 hypogonadal transplant recipients were included (29 no treatment; 58 treated). Treatment modalities included non-testosterone therapies (human chorionic gonadotropin, clomiphene), topical, injectable, and subcutaneous T preparations. There was no difference between groups for baseline characteristics including age, length of follow-up since transplant, baseline testosterone, and transplant type. There was no difference in prostate cancer diagnoses, erythrocytosis, rejection, infections, number of unplanned admissions per patient. While there was no difference in the proportion of deaths in untreated (21%; n = 6) and treated transplant recipients (7%; n = 4; p = 0.08), the median survival was longer in men treated with T (p = 0.03). Treatment of hypogonadism in solid organ recipients did not increase the risk for adverse effects related to treatment of hypogonadism or solid organ transplant.

Stability of Oxandrolone in Medium-Chain Triglyceride Oil and Pharmacokinetics Following Buccal Administration of the Extemporaneous Formulation in Neonates and Adults

OBJECTIVES Growth failure following surgical palliation of complex congenital heart defects (CHDs) is a prognosticator of poor outcomes. Many strategies for improving weight gain have been implemented in this population, with limited success. We recently described the potential of the anabolic steroid oxandrolone to improve weight gain following surgical repair of CHD when administered via a medium-chain triglyceride (MCT) oil suspension to the buccal mucosa. The current study evaluates the stability of oxandrolone in the MCT oil formulation, as well as the pharmacokinetics of oxandrolone when administered via buccal mucosa in both neonates and adults.

METHODS Stability was assessed by long-term storage of the preparation 1) at ambient conditions and 2) under photodegradative conditions for 3 days. Neonatal pharmacokinetic parameters were determined in a cohort of neonates following surgical CHD repair, whereas adult pharmacokinetics parameters were collected as part of a prospective study to evaluate the relative bioavailability of the oxandrolone in MCT oil formulation.

RESULTS We found that oxandrolone was stable in the MCT oil formulation for at least 1 month, although exposure to light hastened drug degradation. Both neonatal and adult oxandrolone pharmacokinetics were variable; however, oxandrolone in MCT oil was relatively well absorbed through the buccal mucosa (mean bioavailability = 62.5%).

CONCLUSIONS These data suggest that the variability in oxandrolone exposures is inherent to the drug, and not the formulation or route of administration. Combined, these data support further study of this novel oxandrolone in MCT oil formulation and its impact on growth following complex surgical repair of CHD in neonates.

Management of Anabolic Steroid-Induced Infertility: Novel Strategies for Fertility Maintenance and Recovery

There is often inherent conflict in the overlapping fields of male fertility and andrology. While the goal of all male fertility specialists is to facilitate and preserve biologic paternity, many practitioners also care for a significant number of patients suffering from hypogonadism. Exogenous testosterone administration, the gold standard for the management of these patients, almost universally impairs spermatogenesis and can even completely eradicate it in some men. With steady increases in both the incidence of hypogonadism and average paternal age, practitioners are now encountering hypogonadal men who desire future fertility or men suffering the effects of earlier androgenic anabolic steroid use with increasing frequency. In this manuscript, we review management strategies for these complex patients and explore novel medications that may be of use in this population.

Digoxin Use in Infants with Single Ventricle Physiology: Secondary Analysis of the Pediatric Heart Network Infant Single Ventricle Trial Public Use Dataset

Digoxin has been associated with reduced interstage mortality after Norwood procedure. We sought to determine its association with survival and change in weight-for-age Z-score (WAZ) before the superior cavopulmonary connection (SCPC) surgery and at 14 months in a heterogeneous group of single ventricle infants. We performed a post-hoc analysis of the Pediatric Heart Network Infant Single Ventricle public use dataset to determine associations between digoxin and survival, transplant-free survival, and change in WAZ pre-SCPC and at 14 months. Sub-analyses of survival and transplant-free survival were performed for subjects who underwent Damus-Kaye-Stansel (DKS)/Norwood. Propensity score weighting was used in Cox hazard-proportion models. Of 229 subjects, 82 (36%) received digoxin and 147 (64%) received no digoxin. Pre-SCPC and 14-month survival and transplant-free survival were not significantly different between the digoxin and no digoxin groups for the main cohort and DKS/Norwood sub-group. However, in DKS/Norwood subjects there was a trend towards improved interstage transplant-free survival in the digoxin group (95.7 vs. 89.6%, p = 0.08). Digoxin was associated with a greater decrease in WAZ from birth to pre-SCPC (- 1.96 ± 0.19 vs. - 1.31 ± 0.18, p < 0.001) and birth to 14 months (- 0.64 ± 0.15 vs. - 0.19 ± 0.15, p = 0.03). Digoxin was not associated with improved survival during the interstage or at 14 months in a mixed single ventricle cohort, but there was a trend towards improved interstage transplant-free survival in post-Norwood infants. As digoxin was associated with poorer weight gain, further research is needed to identify the risks/benefits for anatomic subtypes of infants with single ventricles.