Surgical strategies for the management of end-stage heart failure in infants and children: A 15-year experience with a patient-tailored approach

Intracorporeal LVAD implantation in pediatric patients: A single-center 10 years' experience

BACKGROUND

Mechanical cardiac support is currently an effective strategy to reduce morbidity and mortality in pediatric patients. However, solid evidence regarding the feasibility of intracorporeal devices in children still needs to be provided. We report our 10-year experience with intracorporeal left ventricular assist devices (LVAD) in children.

MATERIALS AND METHODS

We included all patients undergoing intracorporeal, continuous-flow LVAD implantation between 2012 and 2022. Baseline and postoperative data were collected from the institutional database.

RESULTS

Seven HeartWare and 4 HeartMate3 were implanted in 11 patients (median age 13.9 years, median body surface area - BSA - 1.42 m2, IQR 1.06-1.68). The most frequent indication to LVAD implant was dilated cardiomyopathy (72.7%). All candidates underwent a thorough preoperative advanced imaging. Three-dimensional reconstructions and implant fit simulation were performed when BSA was <1.2 m2, weight <30 kg, or internal transverse thoracic diameter <20 cm. There was no operative death. The most common postoperative complication was surgical re-exploration due to bleeding (27.3%). One patient died of severe neurological complications after about 3 months of hospitalization. No late deaths or unplanned re-hospitalizations occurred in the remaining 10, 6 of whom were discharged home. There were no major complications at the follow-up. All survivors underwent successful heart transplantation.

CONCLUSIONS

Intracorporeal LVAD implantation proved to be a potentially feasible and safe option in young teenagers and children whose BSA was >1.0 m2. In borderline cases, the 3D reconstruction with implant fit simulation can effectively help to identify those patients who can safely undergo intrathoracic LVAD implantation.

Myocardial recovery in children supported with a durable ventricular assist device-a systematic review

OBJECTIVES

A small percentage of paediatric patients supported with a ventricular assist device (VAD) can have their device explanted following myocardial recovery. The goal of this systematic review is to summarize the current literature on the clinical course in these children after weaning.

METHODS

A systematic literature search was performed on 27 May 2022 using Embase, Medline ALL, Web of Science Core Collection, Cochrane Central Register of Controlled Trials and Google Scholar to include all literature on paediatric patients supported by a durable VAD during the last decade. Overlapping study cohorts and registry-based studies were filtered out.

RESULTS

Thirty-seven articles were included. Eighteen of them reported on the incidence of recovery in cohort studies, with an overall incidence rate of 8.7% (81/928). Twenty-two of the included articles reported on clinical outcomes after VAD explantation (83 patients). The aetiologies varied widely and were not limited to diseases with a natural transient course like myocarditis. Most of the patients in the included studies (70; 84.3%) were supported by a Berlin Heart EXCOR, and in 66.3% (55/83), only the left ventricle had to be supported. The longest follow-up period was 19.1 years, and multiple studies reported on long-term myocardial recovery. Fewer than half of the reported deaths had a cardiac cause.

CONCLUSIONS

Myocardial recovery during VAD support is dependent on various contributing components. The interactions among patient-, device-, time- and hospital-related factors are complex and not yet fully understood. Long-term recovery after VAD support is achievable, even after a long duration of VAD support, and even in patients with aetiologies different from myocarditis or post-cardiotomy heart failure. More research is needed on this favourable outcome after VAD support.

Late left ventricular myocardial remodeling after pulmonary artery banding for end-stage dilated cardiomyopathy in infants: An imaging study

BACKGROUND

Understanding the macroscopic biventricular changes induced by pulmonary artery banding (PAB) in children with dilated cardiomyopathy (DCM) represents the first step to unraveling the regenerative potential of the myocardium. We herein investigated the phases of left ventricular (LV) rehabilitation in PAB responders, using a systematic echocardiographic and cardiac magnetic imaging (CMRI) surveillance protocol.

METHODS

We prospectively enrolled all patients with DCM treated with PAB from September-2015 at our institution. Among 9 patients, 7 positively responded to PAB and were selected. Transthoracic 2D echocardiography was performed before PAB; and 30, 60, 90, and 120 days after PAB; and at the last available follow-up. CMRI was performed before PAB (whenever possible) and one year after PAB.

RESULTS

In PAB responders, LV ejection fraction showed a modest 10% increase 30-60 days after PAB, followed by its almost complete normalization after 120  days (median of 20[10-26]% vs 56[44.5-63.5]%, at baseline and 120 days after PAB, respectively). Parallelly, the LV end-diastolic volume decreased from a median of 146(87-204)ml/m2 to 48(40-50)ml/m2. At the last available follow-up (median of 1.5 years from PAB), both echocardiography and CMRI showed a sustained positive LV response, although myocardial fibrosis was detected in all patients.

CONCLUSIONS

Echocardiography and CMRI show that PAB can promote a LV remodeling process, which starts slowly and can culminate in the normalization of LV contractility and dimensions 4 months later. These results are maintained up to 1.5 years. However, CMRI showed residual fibrosis as evidence of a past inflammatory injury whose prognostic significance is still uncertain.

Chronic Heart Failure in Children: State of the Art and New Perspectives

Pediatric heart failure (HF) is an important clinical condition with high morbidity and mortality. Compared to adults, pediatric HF shows different etiologies characterized by different physiology, a different clinical course, and deeply different therapeutic approaches. In the last few years, new drugs have been developed and new therapeutic strategies have been proposed with the goal of identifying an individualized treatment regimen. The aim of this article is to review the new potential drugs and non-pharmacological therapies for pediatric heart failure in children.

Rodent Models of Dilated Cardiomyopathy and Heart Failure for Translational Investigations and Therapeutic Discovery

Even with modern therapy, patients with heart failure only have a 50% five-year survival rate. To improve the development of new therapeutic strategies, preclinical models of disease are needed to properly emulate the human condition. Determining the most appropriate model represents the first key step for reliable and translatable experimental research. Rodent models of heart failure provide a strategic compromise between human in vivo similarity and the ability to perform a larger number of experiments and explore many therapeutic candidates. We herein review the currently available rodent models of heart failure, summarizing their physiopathological basis, the timeline of the development of ventricular failure, and their specific clinical features. In order to facilitate the future planning of investigations in the field of heart failure, a detailed overview of the advantages and possible drawbacks of each model is provided.

Functional regeneration of dilated cardiomyopathy by transcatheter bilateral pulmonary artery banding: first-in-human case series

Background

Dilated cardiomyopathy (DCM) is a leading cause of heart transplantation (HTx) in children. Surgical pulmonary artery banding (PAB) is used worldwide to achieve functional heart regeneration and remodelling.

Case summary

We report for the first-time successful bilateral transcatheter implantation of bilateral pulmonary artery flow restrictors in a case series of three infants with severe DCM based on left-ventricular non-compaction morphology associated with Barth syndrome in one and a non-classified syndrome in another. Functional cardiac regeneration was observed in two patients after almost 6 months of endoluminal banding, and in the neonate with Barth syndrome already after 6 weeks. Accompanied by an improvement in functional class (Class IV to Class I), the left ventricular end-diastolic dimensions z-score normalized, as did the elevated serum brain natriuretic peptide levels. A listing for HTx could be avoided.

Discussion

Percutaneous bilateral endoluminal PAB is a novel minimally invasive approach that enables functional cardiac regeneration in infants with severe DCM and preserved right ventricular function. Interruption of the ventriculo-ventricular interaction, the key mechanism for recovery, is avoided. Intensive care for these critically ill patients is reduced to a minimum. However, investing in 'heart regeneration to avoid transplantation' remains a challenge.

Pulmonary Artery Banding for Dilated Cardiomyopathy in Children: Returning to the Bench from Bedside

Current treatment paradigms for end-stage dilated cardiomyopathy (DCM) in children include heart transplantation and mechanical support devices. However, waitlist mortality, shortage of smaller donors, time-limited durability of grafts, and thrombo-hemorrhagic events affect long-term outcomes. Moreover, both these options are noncurative and cannot preserve the native heart function. Pulmonary artery banding (PAB) has been reinvented as a possible “regenerative surgery” to retrain the decompensated left ventricle in children with DCM. The rationale is to promote positive ventricular–ventricular interactions that result in recovery of left ventricular function in one out of two children, allowing transplantation delisting. Although promising, global experience with this technique is still limited, and several surgical centers are reluctant to adopt PAB since its exact biological bases remain unknown. In the present review, we summarize the clinical, functional, and molecular known and supposed working mechanisms of PAB in children with DCM. From its proven efficacy in the clinical setting, we described the macroscopic geometrical and functional changes in biventricular performance promoted by PAB. We finally speculated on the possible underlying molecular pathways recruited by PAB. An evidence-based explanation of the working mechanisms of PAB is still awaited to support wider adoption of this surgical option for pediatric heart failure.