Angiotensin-Converting Enzyme Inhibitor Prescription for Patients With Single Ventricle Physiology Enrolled in the NPC-QIC Registry

Outcomes of Children With Hypoplastic Left Heart Syndrome and Heart Failure on Medical Therapy

Background

Systemic right ventricle (RV) dysfunction is associated with lower transplant-free survival (TFS) in hypoplastic left heart syndrome (HLHS), but the likelihood of functional improvement and utility of heart failure (HF) medications is not understood.

Objectives

The authors aimed to describe TFS, HF medication use, and surgical interventions in HLHS patients with RV dysfunction with and without subsequent improvement in function.

Methods

The SickKids HF Database is a retrospective cohort that includes all pediatric HLHS patients with RV dysfunction lasting >30 days. We compared TFS, HF medications, and surgical interventions in HLHS patients with and without functional normalization.

Results

Of 99 patients with HLHS and RV dysfunction, 52% had normalized function for ≥30 days. TFS at 2 years after dysfunction onset was lower in those without normalization (14% vs 78%, P < 0.001). Patients without normalization were less likely to reach target dosing (TD) of HF medications (27% vs 47% on 1 medication at TD, P < 0.001) and undergo Fontan completion (7% vs 53%, P < 0.001). Clinical factors associated with improved TFS were normalization of function for ≥30 days, onset of dysfunction after bidirectional Glenn, and exposure to ACE inhibition.

Conclusions

Our cohort of HLHS patients with systemic RV dysfunction demonstrated a novel finding of improved TFS in those with functional normalization for ≥30 days. Achieving TD of HF medications was associated with improved outcomes. This may reflect patient stability and tolerance for HF medication more than its therapeutic effect, but it can help inform decisions to proceed with surgical palliation or list for transplant.

Paediatrician's guide to post-operative care for functionally univentricular CHD: a review

IMPORTANCE

Single ventricle CHD affects about 5 out of 100,000 newborns, resulting in complex anatomy often requiring multiple, staged palliative surgeries. Paediatricians are an essential part of the team that cares for children with single ventricle CHD. These patients often encounter their paediatrician first when a complication arises, so it is critical to ensure the paediatrician is knowledgeable of these issues to provide optimal care.

OBSERVATIONS

We reviewed the subtypes of single ventricle heart disease and the various palliative surgeries these patients undergo. We then searched the literature to detail the general paediatrician's approach to single ventricle patients at different stages of surgical palliation.

CONCLUSIONS AND RELEVANCE

Single ventricle patients undergo staged palliation that drastically changes physiology after each intervention. Coordinated care between their paediatrician and cardiologist is requisite to provide excellent care. This review highlights what to expect when these patients are seen by their paediatrician for either well child visits or additional visits for parental or patient concern.

Current evidence for pharmacologic therapy following stage 1 palliation for single ventricle congenital heart disease

INTRODUCTION

Infants with single ventricle congenital heart disease are vulnerable to complications between stage 1 and stage 2 of palliation. Pharmaceutical treatment during this period is varied and often dependent on institutional practices as there is little evidence supporting a particular treatment path.

AREAS COVERED

This review focuses on medical management of patients following stage I palliation. We performed a scoping review of the current literature regarding angiotensin converting enzyme inhibitors and digoxin treatment in the interstage period. In addition, we discuss other medication classes frequently used in these patients.

EXPERT OPINION

Due to significant heterogeneity of anatomy, rarity of disease, and other confounding factors, there is limited evidence to support most commonly used medications within the interstage period. Digoxin is associated with improved mortality within the interstage period and should be considered; however, no large randomized controlled trial exists supporting its use. Prevention of thrombotic complication with aspirin is also associated with improved outcomes and should be considered unless a contraindication exists. The addition of other prescriptions in this patient population should be considered only after an evaluation of the risks and benefits of each medication, recognizing the burden and risk of polypharmacy in this fragile patient population.

Can Pediatric Heart Failure Therapy Be Improved? Yes It Can, But…

Given the heterogenous etiology of pediatric heart failure (pHF), evidence-based studies improving pHF are unlikely. A paradigm shift towards updated medicine-based evidence is therefore necessary. In view of the life expectancy of children, cardiac regeneration strategies are required. Therefore, age- and disease-related differences in myocardial (receptor) physiology require individualized precision medicine. First-line diuretic therapy, adopted from the treatment of adults with HF with no chance for recovery, should be questioned in the treatment of pHF with potential for recovery. Inadequate use of diuretics is a common reason for additional stimulation of the neurohumoral axis. Consecutive intravascular volume depletion led to an inadequate treatment with β-blocker and renin-angiotensin-aldosterone antagonists. Given the age-related catecholamine-driven cardiovascular (patho-) physiology, highly selective β1-blockers (bisoprolol) protect against β1-(noradrenaline)-related myocytic apoptosis and necrosis, but allow β2-receptor-mediated myocardial regeneration. Based on its high safety-efficacy profile with rarely seen adverse effects but easily monitorable efficacy by the surrogate of heart rate (reduction), bisoprolol is our first-line drug in infancy. Reduced heart rate economizes the heart and full body oxygen consumption and extends the diastolic filling and coronary perfusion time. Based on our many years of institutional experience, physicians should be encouraged to use β1-selected blockers in infants with dilated cardiomyopathy and hypoplastic left heart syndrome after stage-1 procedure, but also to treat ventricular septal defects with a significant left-to-right shunt. In summary, individualized pHF therapy is the prerequisite for a causal treatment to improve HF symptoms, but above all for the most functional regeneration possible.

A word on netting of angiotensin-converting enzyme inhibitor therapy in hypoplastic left heart syndrome following stage-I

NPC-QIC Registry data showed that angiotensin-converting enzyme inhibitors were described in almost 38% for patients with single ventricle physiology after stage-I Norwood palliation. However, mortality and ventricular dysfunction or atrioventricular valve insufficiency seems to be not improved by oral application of angiotensin-converting enzyme inhibitors. The final conclusion was that despite limited evidence of benefit for patients with hypoplastic left heart syndrome, prescription of angiotensin-converting enzyme inhibitors during interstage is still common. Taking into account of the predominant cardiovascular regulation in newborns and young infants by circulating catecholamines, no real improvement is to be expected from angiotensin-converting enzyme inhibitor monotherapy. The goals of drug therapy after stage-I Norwood palliation in hypoplastic left heart syndrome are prevention of systemic right ventricle failure, balancing pulmonary and systemic blood flow, and reduction of oxygen consumption with regard to limitations of oxygen supply by the single ventricle, furthermore, avoiding harmful effects of endogenous catecholamine production in the long term on somatic and cognitive development. In this light of knowledge, we want to recommend the use of a long-acting and highly specific ß1-adrenoreceptor blocker for almost all patients after stage-I Norwood palliation and a combination with angiotensin-converting enzyme inhibitors only by indication after exclusion of potential side effects.

Changes in Provider Prescribing Behavior for Infants with Single Ventricle Physiology After Evidence-Based Publications

BACKGROUND

The impact of published evidence on clinical practice has been understudied in pediatric cardiology.

OBJECTIVE

We sought to assess changes in prescribing behavior for angiotensin-converting enzyme inhibitor (ACEI) and digoxin at discharge after initial palliation of infants with single ventricle (SV) physiology following the publication of two large studies: The Pediatric Heart Network Infant Single Ventricle (PHN-ISV) trial showing no benefit with routine ACEI use and the National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) analysis showing an association between digoxin and survival.

METHODS

ICD-9-10 codes identified SV infants from the Pediatric Health Information System (1/2004 to 1/2018) and charge codes identified medications at discharge. Generalized estimating equations implementing segmented logistic regressions modeled medication use, before and after (with a 3-month washout period) the relevant publication (ACEI 7/1/2010; digoxin 4/1/2016). A subgroup analysis was performed for hypoplastic left heart syndrome (HLHS).

RESULTS

ACEI use (37 centers, n = 4700) at discharge did not change over time during the pre-publication period. After publication of the PHN-ISV trial, ACEI use decreased (OR: 0.61, CI 0.44-0.84, p = 0.003). Digoxin use (43 centers, n = 4778) decreased by 1% monthly before publication. After the NPC-QIC publication, digoxin use increased (OR: 2.07, CI 1.05-4.08, p = 0.04) with an ongoing increase of 9% per month. Results were similar for the HLHS subgroup.

CONCLUSIONS

Prescribing behavior changed congruently after the publication of evidence-based studies, with decreased ACEI use and increased digoxin use at discharge following initial palliation of SV infants. Our findings suggest scientific findings were rapidly implemented into clinical practice.

Cardiovascular Drug Therapy during Interstage After Hybrid Approach: A Single-Center Experience in 51 Newborns with Hypoplastic Left Heart

BACKGROUND

Newborns with hypoplastic left heart (HLH) are usually palliated with the Norwood procedure or a hybrid stage I procedure. Hybrid is our preferred approach. Given the critical relationship between stage I, interstage, and comprehensive stage II or advanced biventricular repair, we hypothesized that appropriate drug treatment is a significant therapeutic cornerstone, especially for the management of the high-risk interstage.

METHODS

We report a single-center observational study addressing the cardiovascular effects of, in particular, oral β-blockers and the additional use of angiotensin-converting enzyme (ACE) and mineralocorticoid inhibitors.

RESULTS

In total, 51 newborns-30 with HLH syndrome (HLHS) and 21 with HLH complex (HLHC)-with a median bodyweight of 3.0 kg (range 1.9-4.4; nine with bodyweight ≤ 2500 g) underwent an uneventful "Giessen hybrid approach" using a newly approved duct stent. All patients were discharged home with a single, double or triple therapy consisting of ß-blockers, ACE and mineralocorticoid inhibitors; 90% of the patients received bisoprolol, 10% received propranolol, 72% received lisinopril, and 78% received spironolactone. Resting heart rate decreased from 138 bpm (range 112-172; n = 51) at admission to 123 bpm (range 99-139; n = 51) at discharge and 110 bpm before stage II/biventricular repair/heart transplantation (range 90-140; n = 37) accompanied by favorable bodyweight gain. No side effects were evident.

CONCLUSION

In view of drug risk/benefit profiles, as well as the variable morphology and hemodynamics, the highly selective β1-adrenoceptor blocker bisoprolol is our preferred drug for treatment of HLHS/HLHC in the interstage. We avoid using ACE inhibitor monotherapy and exclude potential risks for coronary and cerebral perfusion pressure beforehand.

Angiotensin-Converting Enzyme Inhibitor Prescription for Patients With Single Ventricle Physiology Enrolled in the NPC-QIC Registry

Background

The routine use of angiotensin‐converting enzyme inhibitors (ACEI) during palliation of hypoplastic left heart syndrome is controversial. We sought to describe ACEI prescription in the interstage between stage 1 palliation (stage I Norwood procedure) discharge and stage 2 palliation (stage II superior cavopulmonary anastomosis procedure) admission using the NPC‐QIC (National Pediatric Cardiology Quality Improvement Collaborative) registry.

Methods and Results

Analysis of all patients (n=2180) enrolled in NPC‐QIC from 2008 to 2016 included preoperative anatomy, risk factors, and echocardiographic data. ACEI were prescribed at stage I Norwood procedure discharge in 38% of patients. ACEI prescription declined from 2011 to 2016 compared with pre‐2010 (36.8% versus 45%; P=0.005) with significant variation across centers (range 7–100%; P<0.001) and decreased prescribing rates associated with increased center volume (P=0.004). There was no difference in interstage mortality (P=0.662), change in atrioventricular valve regurgitation (P=0.101), or change in ventricular dysfunction (P=0.134) between groups. In multivariable analysis of all patients, atrioventricular septal defect (odds ratio [OR], 1.84; 95% CI, 1.28–2.65) or double outlet right ventricle (OR, 1.47; CI, 1.02–2.11), and preoperative mechanical ventilation (OR, 1.37; 95% CI, 1.12–1.68) were associated with increased ACEI prescription. In multivariable analysis of patients with complete echocardiographic data (n=812), ACEI prescription was more common with at least moderate atrioventricular valve regurgitation (OR, 1.88; 95% CI, 1.22–2.31).

Conclusions

ACEI prescription remains common in the interstage despite limited evidence of benefit. ACEI prescription is associated with preoperative mechanical ventilation, double outlet right ventricle, and atrioventricular valve regurgitation with marked inter‐center variation. ACEI prescription is not associated with reduction in mortality, ventricular dysfunction, or atrioventricular valve regurgitation during the interstage.

From Other Journals: A Review of Recent Articles in Pediatric Cardiology

In this review, we provide a brief description of recently published articles addressing topics relevant to pediatric cardiologists. Our aim is to provide a summary of the latest articles published recently in other journals in our field. The articles address (1) cardiac resynchronization in children with symptomatic ventricular dysfunction and dyssynchrony which seems to result in higher transplant-free survival, (2) outcomes of aortic leaflet reconstruction including Ozaki procedure to repair aortic valve disease in adolescents, (3) meta-analysis for risk factors of ventricular tachycardia and death after repaired tetralogy of Fallot which reiterates the known risk factors and showed that the severity of pulmonary regurgitation is not in itself associated with outcomes although the ventricular response to regurgitation (dilation and dysfunction) is, (4) preschool promotion of healthy life style did not associate with sustained effect when evaluated later in childhood although repeated intervention seems to have a dose-related effect to promote healthy life style, (5) the lack of beneficial effects of angiotensin-converting enzyme inhibitors in the interstage period, and (6) a new phenomenon of acute heart failure and multisystem inflammatory syndrome in children temporarily related to the COVID-19 pandemic.