Unique Challenges of Randomised Controlled Trials in Pediatric Cardiology

Twinning International Pediatric Cardiology Fellowship Programs: A Transformative Educational Experience for Trainees with Potential for Global Adoption

Over the last decade, having endured the COVID-19 pandemic, education and training in pediatric cardiology have undergone a profound disruptive transformation. Trainees experience considerable stress achieving all the competencies required to become a competent pediatric cardiologist. Often the quality of the training experienced by trainees, the approach to patients, and potential institutional preference in management strategy is heavily influenced by the center in which they train. We developed an online live twin program of education between Texas Children's Hospital, Houston, Texas and Children's Health at Crumlin Dublin Ireland in 2019. We explored using grounded theory whether a regular scheduled shared teaching program improved fellow education and training between both centers. Trainees were surveyed to evaluate the benefits and disadvantages of such a twin program. The majority (93%) found the sessions helpful from an educational standpoint with many trainees reporting it to be a transformative experience. Three important learning themes emerged: practice variation between centers, managing uncertainty in clinical practice and cognitive overload. This pedagogical model could be replicated across multiple international pediatric cardiology units and facilitate "collaborative learning" among centers across the globe. Furthermore, this novel educational model could also be adopted by other medical specialties.

Evaluating registry-based trial economics: Results from the STRESS clinical trial

Background

Registry-based trials have the potential to reduce randomized clinical trial (RCT) costs. However, observed cost differences also may be achieved through pragmatic trial designs. A systematic comparison of trial costs across different designs has not been previously performed.

Methods

We conducted a study to compare the current Steroids to Reduce Systemic inflammation after infant heart surgery (STRESS) registry-based RCT vs. two established designs: pragmatic RCT and explanatory RCT. The primary outcome was total RCT design costs. Secondary outcomes included: RCT duration and personnel hours. Costs were estimated using the Duke Clinical Research Institute's pricing model.

Results

The Registry-Based RCT estimated duration was 31.9 weeks greater than the other designs (259.5 vs. 227.6 weeks). This delay was caused by the Registry-Based design's periodic data harvesting that delayed site closing and statistical reporting. Total personnel hours were greatest for the Explanatory design followed by the Pragmatic design and the Registry-Based design (52,488 vs 29,763 vs. 24,480 h, respectively). Total costs were greatest for the Explanatory design followed by the Pragmatic design and the Registry-Based design ($10,140,263 vs. $4,164,863 vs. $3,268,504, respectively). Thus, Registry-Based total costs were 32 % of the Explanatory and 78 % of the Pragmatic design.

Conclusion

Total costs for the STRESS RCT with a registry-based design were less than those for a pragmatic design and much less than an explanatory design. Cost savings reflect design elements and leveraging of registry resources to improve cost efficiency, but delays to trial completion should be considered.

Research Gaps in Pediatric Heart Failure: Defining the Gaps and Then Closing Them Over the Next Decade

Given the numerous opportunities and the wide knowledge gaps in pediatric heart failure, an international group of pediatric heart failure experts with diverse backgrounds were invited and tasked with identifying research gaps in each pediatric heart failure domain that scientists and funding agencies need to focus on over the next decade.

Milrinone for the treatment of heart failure caused by severe Pneumonia in children with congenital heart disease: a meta-analysis

BACKGROUND

Children with congenital heart disease (CHD) are easily complicated by severe pneumonia and heart failure. We aimed to conduct a meta-analysis to evaluate the effects and safety of milrinone for the treatment of heart failure caused by severe pneumonia in children with CHD to provide evidence for the clinical CHD treatment.

METHODS

Two authors searched MEDLINE, PubMed, Embase, Science Direct, Cochrane Central Register of Controlled Trials, the Cochrane Library, Wanfang database, Chinese Biomedical Literature Database, China National Knowledge Infrastructure (CNKI) for randomized controlled trials (RCTs) about the application of milrinone in the treatment of heart failure caused by severe pneumonia in children with CHD in children up to December 10, 2022. Two evaluators independently selected the literature, extracted data and evaluated the methodological quality, meta-analysis was carried out with RevMan 5.3 software.

RESULTS

Eight RCTs involving 680 CHD children complicated by severe pneumonia and heart failure were included in this meta-analysis. Meta-analysis indicated that total effective rate of the milrinone group was higher than that of control group (RR = 1.25, 95%CI: 1.17 ~ 1.34, P < 0.001), the time to stable heart rate of the milrinone group was less than that of control group (RR=-0.88, 95%CI: -1.09~ -0.67, P < 0.001). The time to stable respiration of the milrinone group was less than that of control group (RR=-0.98, 95%CI: -1.17~ -0.78, P < 0.001). The LVEF of the milrinone group was higher than that of control group (RR = 6.46, 95%CI: 5.30 ~ 7.62, P < 0.001). There was no significant difference in the incidence of adverse reactions between the milrinone group and control group (RR = 0.85, 95%CI: 0.47 ~ 1.56, P = 0.061). Funnel plots and Egger regression test results indicated that there were no statistical publication bias amongst the synthesized outcomes (all P > 0.05).

CONCLUSIONS

Milrinone is beneficial to improve clinical symptoms and cardiac function and increase the therapeutic effect and safety in children with CHD complicated by severe pneumonia and heart failure. However, more RCTs with large samples and rigorous design are needed to verify this finding.

Guiding future paediatric drug studies based on existing pharmacokinetic and efficacy data: Cardiovascular drugs as a proof of concept

INTRODUCTION

Off-label drug use in the paediatric population is common, and the lack of high-quality efficacy studies poses patients at risk for failing pharmacotherapy. Next to efficacy studies, pharmacokinetic (PK) studies are increasingly used to inform paediatric dose selection. As resources for paediatric trials are limited, we aimed to summarize existing PK and efficacy studies to identify knowledge gaps in available evidence supporting paediatric dosing recommendations, thereby taking paediatric cardiovascular drugs as proof of concept.

METHODS

For each cardiovascular drug, paediatric indication and prespecified age group, together comprising one record, the authorized state was assessed. Next, for off-label records, the highest level of evidence was scored. High-quality efficacy studies were defined as meta-analysis or randomized controlled trials. Other comparative research, noncomparative research or consensus-based expert opinions were considered low quality. The level of evidence for PK studies was scored per drug and per age group, but regardless of indication.

RESULTS

A total of 58 drugs included 417 records, of which 279 (67%) were off-label. Of all off-label records, the majority (81%) were not supported by high-quality efficacy studies, but for 140 of these records (62%) high-quality PK studies were available.

CONCLUSION

We demonstrated that for the majority of off-label cardiovascular drugs, only low-quality efficacy studies were available. However, high-quality PK studies were frequently available. Combining these PK data with extrapolation of efficacy data from adults may help to close the current information gap and prioritize the drugs for which clinical studies and safety data are urgently needed.

The paucity of high-level evidence for therapy in pediatric cardiology

Introduction

Clinical practice should be based on the highest quality of evidence available. Therefore, we aimed to classify publications in the field of pediatric cardiology in the year 2021 based on the level of scientific evidence.

Materials and Methods

A PubMed search was performed to identify pediatric cardiology articles published in the calendar year 2021. The abstract or manuscript of each study was reviewed. Each study was categorized as high, medium, or low level of evidence based on the study design. Disease investigated, treatment studied, and country of publication were recorded. Randomized control trials (RCTs) in similar fields of neonatology and adult cardiology were identified for comparison. Descriptive statistics were performed on the level of evidence, type of disease, country of publication, and therapeutic intervention.

Results

In 2021, 731 studies were identified. A decrease in prevalence for the level of evidence as a function of low, medium, and high was found (50.1%, 44.2%, and 5.8%, respectively). A low level of evidence studies was the majority for all types of cardiac disease identified, including acquired heart disease, arrhythmias, congenital heart disease, and heart failure, and for treatment modalities, including circulatory support, defibrillator, percutaneous intervention, medicine, and surgery. In a subgroup analysis, most high-level evidence studies were from the USA (31%), followed by China (26.2%) and India (14.3%). Comparing RCTs, 21 RCTs were identified in pediatric cardiology compared to 178 in neonatology and 413 in adult ischemic heart disease.

Conclusions

There is a great need for the conduct of studies that offer a high level of evidence in the discipline of pediatric cardiology.

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.

Treatment Strategies for Cardiomyopathy in Children: A Scientific Statement From the American Heart Association

This scientific statement from the American Heart Association focuses on treatment strategies and modalities for cardiomyopathy (heart muscle disease) in children and serves as a companion scientific statement for the recent statement on the classification and diagnosis of cardiomyopathy in children. We propose that the foundation of treatment of pediatric cardiomyopathies is based on these principles applied as personalized therapy for children with cardiomyopathy: (1) identification of the specific cardiac pathophysiology; (2) determination of the root cause of the cardiomyopathy so that, if applicable, cause-specific treatment can occur (precision medicine); and (3) application of therapies based on the associated clinical milieu of the patient. These clinical milieus include patients at risk for developing cardiomyopathy (cardiomyopathy phenotype negative), asymptomatic patients with cardiomyopathy (phenotype positive), patients with symptomatic cardiomyopathy, and patients with end-stage cardiomyopathy. This scientific statement focuses primarily on the most frequent phenotypes, dilated and hypertrophic, that occur in children. Other less frequent cardiomyopathies, including left ventricular noncompaction, restrictive cardiomyopathy, and arrhythmogenic cardiomyopathy, are discussed in less detail. Suggestions are based on previous clinical and investigational experience, extrapolating therapies for cardiomyopathies in adults to children and noting the problems and challenges that have arisen in this experience. These likely underscore the increasingly apparent differences in pathogenesis and even pathophysiology in childhood cardiomyopathies compared with adult disease. These differences will likely affect the utility of some adult therapy strategies. Therefore, special emphasis has been placed on cause-specific therapies in children for prevention and attenuation of their cardiomyopathy in addition to symptomatic treatments. Current investigational strategies and treatments not in wide clinical practice, including future direction for investigational management strategies, trial designs, and collaborative networks, are also discussed because they have the potential to further refine and improve the health and outcomes of children with cardiomyopathy in the future.

Pediatric Heart Network Trial of Losartan vs. Atenolol in Children and Young Adults with Marfan Syndrome: Impact on Prescription Practices

The Pediatric Heart Network (PHN) trial showed similar efficacy of β-blockers (BB) and angiotensin receptor blockers (ARB) for aortic root dilation in Marfan syndrome, but the impact on prescription practices is unknown. We hypothesized BB and ARB prescriptions would increase after the trial results were published (2014). Prescription data (2007-2016) were obtained from outpatient encounters (IBM Marketscan) for Marfan syndrome patients (6 months-25 years old). Excluding 2014 as a washout period, we analyzed two intervals: 2007-2013 and 2015-2016. Medication categories included BB, ARB, angiotensin converting enzyme inhibitors (ACEI), combination (BB/ARB and/or BB/ACEI), and no drug. Interrupted time-series analysis assessed immediate level change after publication and change in slope for the trend pre- and post-publication. Odds ratios (OR) and 95% confidence intervals from logistic regressions and generalized estimating equation methods accounted for correlation of prescriptions within patients. In 1499 patients (age 14.1 ± 6.1 years, 59% female) seen 2007-2013, BB trended lower [OR 0.91 (0.89, 0.93), p < 0.001] and ARB trended higher [OR 1.12 (1.07, 1.18), p < 0.001], while combination, ACEI, and no drug remained stable. This trend persisted, but was not significant, for BB [OR 0.54 (0.27, 1.08), p = 0.37] and ARB [OR 1.91 (0.55, 6.69), p = 0.31] in 2015-2016. Combination, ACEI, and no drug remained similar. In short term follow-up, changes in prescription practices following publication of the PHN trial were not statistically significant. This may be due to a change seen prior to publication with early adoption of ARBs that was maintained after confirmation of their effectiveness.

Management of Multisystem Inflammatory Syndrome in Children: Decision-Making Regarding a New Condition in the Absence of Clinical Trial Data

Multisystem inflammatory syndrome in children (MIS-C) is a new illness that evolved during the COVID-19 pandemic with initial reports of severe disease including use of extracorporeal membrane oxygenation and death. Institutions rapidly assembled task forces to develop treatment algorithms. At the national/international levels, collaboratives and associations assembled consensus writing groups to draft guidelines. These guidelines and algorithms were initially on the basis of expert opinion and small case series. Some groups used the Delphi approach, and the resultant guidelines often mimicked those for other conditions that resembled MIS-C, like Kawasaki disease (KD). For instance, intravenous immunoglobulin (IVIG), a known effective treatment for KD, was recommended for MIS-C. Early in the pandemic many favoured IVIG over steroids as first-line therapy. As evidence evolved so did some guidelines, which now endorse the dual use of IVIG with steroids as first-line therapy. In contrast, withholding immunotherapy became an option for some MIS-C patients with mild symptoms. Herein, we review guidelines and discuss the evidence informing early recommendations, how this has evolved, the role and limitations of expert opinion and observational data, and the importance of leveraging existing research infrastructures, such as the intensive care unit collaborative (Overcoming COVID-19 surveillance registry), and the International Kawasaki Disease Registry. Finally, we discuss strategies to rapidly develop, deploy, and adapt clinical trials evaluating the treatment of such rare conditions in children, which might include alternatives to conventional clinical trial design. The emergence of MIS-C during the COVID-19 pandemic has highlighted unmet needs regarding research of a new condition.

Medicine-Based Evidence in Congenital Heart Disease: How Artificial Intelligence Can Guide Treatment Decisions for Individual Patients

Built on the foundation of the randomized controlled trial (RCT), Evidence Based Medicine (EBM) is at its best when optimizing outcomes for homogeneous cohorts of patients like those participating in an RCT. Its weakness is a failure to resolve a clinical quandary: patients appear for care individually, each may differ in important ways from an RCT cohort, and the physician will wonder each time if following EBM will provide best guidance for this unique patient. In an effort to overcome this weakness, and promote higher quality care through a more personalized approach, a new framework has been proposed: Medicine-Based Evidence (MBE). In this approach, big data and deep learning techniques are embraced to interrogate treatment responses among patients in real-world clinical practice. Such statistical models are then integrated with mechanistic disease models to construct a “digital twin,” which serves as the real-time digital counterpart of a patient. MBE is thereby capable of dynamically modeling the effects of various treatment decisions in the context of an individual's specific characteristics. In this article, we discuss how MBE could benefit patients with congenital heart disease, a field where RCTs are difficult to conduct and often fail to provide definitive solutions because of a small number of subjects, their clinical complexity, and heterogeneity. We will also highlight the challenges that must be addressed before MBE can be embraced in clinical practice and its full potential can be realized.