HomeCirculation: Cardiovascular InterventionsVol. 6, No. 1Circulation: Cardiovascular Interventions Editors’ Picks Free AccessResearch ArticlePDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessResearch ArticlePDF/EPUBCirculation: Cardiovascular Interventions Editors’ PicksMost Important Articles in Congenital Heart Disease The Editors The Editors Search for more papers by this author Originally published1 Feb 2013https://doi.org/10.1161/CIRCINTERVENTIONS.112.000176Circulation: Cardiovascular Interventions. 2013;6:e3–e6Pulmonary Vascular DiseaseRandomized Trial of Cutting Balloon Compared With High-Pressure Angioplasty for the Treatment of Resistant Pulmonary Artery StenosisSummary: Children born with congenital heart disease not uncommonly require cardiac catheterization to treat congenital and acquired malformations such as pulmonary artery stenosis, replacing or complementing surgical techniques. In this study of cutting balloons compared with high-pressure balloon angioplasty for resistant pulmonary artery stenosis, the authors have shown superior efficacy with the cutting balloon technology and an equivalent safety profile. This finding has important clinical application for a population with previously untreatable disease. Although few studies have evaluated the performance of devices developed for adults but used in children, in this study, the authors have demonstrated that some of the unique study design and execution difficulties met in the pediatric population can be overcome. The authors hope that future studies will continue to evaluate the performance rigorously of devices used to treat children with rare diseases relative to more common adult indications.Conclusions: CB therapy for pulmonary artery stenosis not responsive to low-pressure balloon is more effective than HPB therapy and has an equivalent safety profile.1Outcomes After Stent Implantation for the Treatment of Congenital and Postoperative Pulmonary Vein Stenosis in ChildrenSummary: Intraluminal pulmonary vein stenosis is a progressive condition that is frequently lethal in children. Treatment approaches for relief of luminal stenosis are acutely successful, but with limited long-term benefit. Although intravascular stents are acutely successful in the relief of luminal stenosis, the rates of restenosis are high. Stents implanted at a larger diameter seem to remain patent longer with lower risk of reintervention.Conclusions: Transcatheter stent implantation can acutely relieve pulmonary vein stenosis in children, but reintervention is common. Larger stent lumen size at implantation is associated with longer stent patency and a lower risk of reintervention.2Balloon Angioplasty and Stenting of Branch Pulmonary Arteries: Adverse Events and Procedural Characteristics: Results of a Multiinstitutional RegistrySummary: This prospective study analyzed basic procedural data and adverse events of 1315 transcatheter pulmonary artery interventional cases. Adverse events occurred in 22% of all cases, and more severe (level 3–5) adverse events occurred in 10% of cases, notably higher than what has been previously reported. Presence of >2 indicators of hemodynamic vulnerability, low weight, use of cutting balloons, as well as operator experience of <10 years were significant independent risk factors for level 3 to 5 procedure-related adverse events. This is very important data because it provides operators for the first time solid data on type and frequency of procedure-related adverse events, which is crucial when counseling patients and families for these procedures. Furthermore, this study now allows a better understanding of risk factors for serious adverse events, which allows a better risk stratification and may reduce the incidence of major procedure-related adverse events.Conclusions: Pulmonary artery rehabilitation is associated with a 10% incidence of high-level severity adverse events. Hemodynamic vulnerability, young age, use of cutting balloons, and lower operator experience were significant independent risk factors for procedure-related AE.3Percutaneous Vascular Stent Implantation as Treatment for Central Vascular Obstruction Because of Fibrosing MediastinitisSummary: Fibrosing mediastinitis (FM) is a rare but devastating late complication of infection with Histoplasma that manifests as a proliferation of fibrous tissue within the mediastinum, obstructing central vessels and airways. In ≈20% of affected individuals, bilateral pulmonary arteries, pulmonary veins, and airways are affected by the dense fibrous material, which portends an especially grave prognosis. Management of FM is particularly challenging to the clinician. To date, no effective pharmacological or surgical therapy has been shown to provide long-term benefit, and whereas percutaneous interventions using stents to relieve vascular obstruction in FM have been reported in single case reports and small case series, few centers have robust experience with vascular stenting for this disease. This review is the largest published series of percutaneous vascular stenting to ameliorate central vascular obstruction in FM. Our results show that vascular stenting is technically feasible and provides sustained symptomatic relief in the majority of patients. Minor complications, including hemoptysis and catheterization site bleeding, were the most common adverse events, and major complications or death after percutaneous intervention were rare. The decision to perform vascular stenting for FM is complex, and should be carefully considered after comprehensive radiographic and hemodynamic evaluation and expert consultation to select candidates properly with greatest chance of sustained success. In the authors’ experience, percutaneous vascular stenting in selected patients with significant bilateral vascular involvement or superior vena cava syndrome from FM is a good option for relief of clinical symptoms, but should be performed at a center experienced in large-vessel stent implantation.Conclusions: Percutaneous vascular stent implantation is an effective therapy for central vascular obstruction because of FM, providing significant relief of anatomic obstruction and sustained clinical improvement.4Valvular Heart DiseaseLong-Term Outcome of Patients With Isolated Thin Discrete Subaortic Stenosis Treated by Balloon Dilation: A 25-Year StudySummary: This study presents the longest follow-up analysis of a series of patients with isolated, thin, discrete subaortic stenosis treated by transluminal balloon tearing of the membrane. Selection of appropriate candidates for percutaneous treatment was an important issue, and only patients with a thin membrane at the outflow tract without a fibromuscular component were included. After a mean follow-up time of 16±6 years, 11 patients (15%) developed restenosis, 3 patients (4%) progressed to muscular obstructive disease, 1 patient (1.3%) developed a new distant obstructive membrane, and 4 patients (5%) underwent surgery at a mean of 3±2 years after their first treatment. Fifty-eight patients (77%) remained alive and free of redilation or surgery at follow-up. Larger annulus diameter and thinner membranes were independent factors associated with better long-term results. These findings, together with current improvements in image techniques for better delineation of the outflow tract, could help in the selection of patients who can benefit from an interventional procedure as a first-choice treatment. The recurrence rate in this selected group of patients may be similar to that observed in surgical patients, and both are probably influenced by the progressive nature of the disease. If restenosis of the membrane develops, balloon dilation can be repeated successfully in most patients. With this strategy, surgery for a thin membrane may be delayed or even avoided.Conclusions: Most patients (77%) with isolated, thin, discrete subaortic stenosis treated with transluminal balloon tearing of the membrane had sustained relief at subsequent follow-ups without restenosis, the need for surgery, progression to muscular obstructive disease, or an increase in the degree of aortic regurgitation.5Left Ventricular Remodeling and Improvement in Diastolic Function After Balloon Aortic Valvuloplasty for Congenital Aortic StenosisSummary: Chronic pressure load on the left ventricle because of aortic stenosis results in ventricular hypertrophy, myocardial fibrosis, and abnormal myocardial mechanics. These processes can result in both systolic and diastolic dysfunction. Diastolic function and noninvasive measures of left atrial pressure improve in the majority of patients after effective relief of aortic stenosis with balloon aortic valvuloplasty.Conclusions: After balloon aortic valvuloplasty, left ventricular remodeling characterized by an increase in end-diastolic volume and decrease in LV mass:volume occurs, and echocardiographic measures of diastolic function and LV end-diastolic pressure improve in most patients. Risk factors for persistent diastolic dysfunction include higher pre-balloon aortic valvuloplasty left ventricular mass z-score and worse pre-BAVP diastolic function.6Short-Term Performance of the Transcatheter Melody Valve in High-Pressure Hemodynamic Environments in the Pulmonary and Systemic CirculationsSummary: The Melody valve is approved for percutaneous pulmonary valve replacement in dysfunctional right ventricular outflow tracts. The functioning of this valve in a low-pressure environment is well established. This initial small series describes the unique use of the Melody valve in the high-pressure environment of the aortic and mitral valves. Short-term follow-up of the Melody valve in a high-pressure environment demonstrates good valve function for 1 year.Conclusions: Short-term performance of the Melody valve in high-pressure environments is encouraging, with good valve function in all patients.7Stent Fracture, Valve Dysfunction, and Right Ventricular Outflow Tract Reintervention After Transcatheter Pulmonary Valve Implantation: Patient-related and Procedural Risk Factors in the US Melody Valve TrialSummary: Transcatheter pulmonary valve placement with the Melody valve is effective in the short term for relief of right ventricular outflow tract obstruction and pulmonary regurgitation in patients with surgically implanted right ventricle-to-pulmonary artery conduits. Stent fracture with associated right ventricular outflow tract obstruction is the most common indication for reintervention after Melody valve placement, but risk factors for stent fracture and reintervention have not been determined. In this series of 150 patients who underwent Melody valve implant as part of the US Investigational Device Exemption trial, the authors analyzed implant conditions, conduit preparation techniques, and valve-related outcomes and documented an ongoing risk of stent fractures, many of which were not associated with hemodynamic valve dysfunction. The authors found that stent fractures were more likely in patients with severely obstructed right ventricular outflow tract conduits and when the Melody was directly behind the anterior chest wall and clearly compressed, whereas a valve implant site protected by a prestent or bioprosthetic valve was associated with lower risk of fracture and reintervention.Conclusions: Melody stent fracture (MSF) was common after transcatheter pulmonary valve (TPV) implant in this multicenter experience, and was more likely in patients with severely obstructed right ventricular outflow tract conduits and when the TPV was directly behind the anterior chest wall and clearly compressed. A TPV implant site protected by a prestent or bioprosthetic valve was associated with lower risk of MSF and reintervention.8Melody Valve Implantation Into the Branch Pulmonary Arteries for Treatment of Pulmonary Insufficiency in an Ovine Model of Right Ventricular Outflow Tract Dysfunction Following Tetralogy of Fallot RepairSummary: Pulmonary insufficiency and consequent right ventricular dilation and dysfunction are common and important problems after transannular patch repair of tetralogy of Fallot. Transcatheter pulmonary valve therapy has provided a means of treating postoperative right ventricular outflow tract dysfunction (pulmonary insufficiency and obstruction) with less morbidity than standard surgical pulmonary valve replacement. However, most patients with chronic pulmonary insufficiency after transannular patch repair of tetralogy of Fallot are ineligible for treatment with the current approaches and technologies because of severe right ventricular outflow tract dilation and distortion, which develops over time, often with concomitant branch pulmonary artery pathology. This anatomic complexity makes it technically impossible to implant currently available and approved valves in the orthotopic (usual) pulmonary position through a transcatheter approach, and therefore, surgery is required to restore pulmonary valve competence. The purpose of this study was to explore alternative locations within the pulmonary arterial tree for valve implantation. The authors demonstrated that Melody valve insertion in the branch pulmonary arteries was feasible and effective at reducing pulmonary insufficiency, and had a favorable effect on both right and left ventricular function in the short term. The authors currently are investigating the effectiveness of this approach in a chronic model. The ultimate goal of this project is to expand the choices that are available to clinicians charged with treating these complex patients.Conclusions: Bilateral branch PA Melody valve implantation significantly reduced pulmonary regurgitation fraction and altered right ventricle and left ventricular function favorably in a model of transannular patch for tetralogy of Fallot. This novel intervention may offer potential benefit in treating patients with anatomically heterogeneous disease of the right ventricular outflow tract.9Melody Valve Implant Within Failed Bioprosthetic Valves in the Pulmonary Position:A Multicenter ExperienceSummary: Transcatheter pulmonary valve replacement within failed right ventricular to pulmonary artery conduits using the Melody valve is effective in the short and intermediate term. However, there is little published information regarding Melody valve implantation into failed bioprosthetic valves in the pulmonary position, which is currently an off-label indication. This series reviews 104 patients who underwent Melody valve implantation into failed bioprosthetic valves in the pulmonary position at 8 centers in the United States, and represents the largest experience published to date. The authors found that Melody valve implant into bioprosthetic valves can be accomplished safely and effectively with low morbidity and mortality, and excellent short-term results.Conclusions: Transcatheter pulmonary valve implantation using the Melody valve within BPVs can be accomplished with a high rate of success, low procedure-related morbidity and mortality, and excellent short-term results. The findings of this preliminary multicenter experience suggest that the Melody valve is an effective transcatheter treatment option for failed Melody-in-bioprosthetic valves.10Other TechniquesClinical and Stent-Related Outcomes After Transcatheter or Operative Placement of Bare-Metal Stents in the Ventricular Septum or Subvalvar Systemic Outflow TractSummary: Stent fracture is a well-recognized complication, particularly when stents are placed near pulsatile or dynamic structures. It is important to better understand the mid-term to long-term fate of stents placed inside the heart, where they are exposed to cyclic, compressive, flexional, and torsional stresses. In patients with obstruction of the left ventricular outflow tract after surgery for congenital heart disease or those with a functionally isolated ventricle at high-pressure, transcatheter, intraoperative, or hybrid stenting of the ventricular septum or left ventricular outflow tract is feasible. These procedures reduce the gradient across the obstruction and the pressure in the hypertensive ventricle. However, the incidence of significant reobstruction was high, and more than one half of the patients in the series underwent reintervention during the follow-up period. There is a high incidence of stent fracture.Conclusions: Transcatheter, intraoperative, or hybrid stenting of the ventricular septum or systemic outflow tract is feasible and effective in the short term. Stent fractures were common during follow-up and associated with recurrent obstruction.11Procedure-Type Risk Categories for Pediatric and Congenital Cardiac CatheterizationSummary: This Congenital Cardiac Catheterization Project on Outcomes (C3PO) currently includes 8 sites collecting data on all cardiac catheterization cases performed at the pediatric institutions. For this project, the participants categorized 84 procedure types into 6 categories using consensus methods based on expert opinion regarding the anticipated risk of an adverse event. After data were collected on nearly 4000 cases, the group used empirical methods to refine the categories and derived 4 categories of procedures with distinct differences in risk of having a clinically important adverse event. The authors anticipate a broad range of uses for these procedure-type risk categories. First, they can be used to understand variations in case mix complexity both among providers and institutions. Practically, they can be used to track trends in provider, hospital, or national populations of patients undergoing catheterization for congenital heart disease. Second, the categories may be useful as a variable in research studies on catheterization for congenital heart disease to understand population characteristics and adjust for risk. Third, the categories may allow a better estimate of risk, when discussing and consenting patients and families for a procedure. Further, when planning for a case, high-risk procedures may necessitate special resources such as rapid extracorporeal membrane oxygenation capability or available surgeons. Finally, procedure-type risk category will ultimately be an important variable to consider in risk-adjustment methods to standardize outcomes among institutions and providers to allow equitable comparisons.Conclusions: Procedure-type risk categories are associated with different complication rates in the dataset and could be an important variable in risk-adjustment models for pediatric catheterization.12Extracorporeal Membrane Oxygenation for Bridge to Heart Transplantation Among Children in the United States: Analysis of Data From the Organ Procurement and Transplant Network and Extracorporeal Life Support Organization RegistrySummary: Extracorporeal membrane oxygenation (ECMO) has served for >2 decades as the standard-of-care for US children requiring mechanical support as a bridge to heart transplantation. Unfortunately, objective data on the safety and efficacy of ECMO for this purpose are limited, in part, because ECMO has never been approved by the Food and Drug Administration for this particular indication. In this study, data from the Extracorporeal Life Support Organization and Organ Procurement Transplant Network registries are combined to describe the efficacy and safety profile of ECMO for a bridge to heart transplantation, and to propose objective performance goals that can be used as benchmarks to facilitate Food and Drug Administration approval of emerging miniaturized cardiac assist devices intended to replace ECMO. Among 733 children supported with ECMO as a bridge to heart transplantation since the mid-1990s, fewer than half survived to hospital discharge. Most deaths occurred while the children were on the wait list, but children successfully transplanted also had high post-transplantation mortality, accounting for up to one third of all in-hospital deaths. The risk of death was not uniform across all patient groups and varied by cardiac diagnosis, end-organ dysfunction, and duration of ECMO support. In the objective performance goal cohort, patients with cardiomyopathy had the highest survival to hospital discharge (63%), followed by patients with myocarditis (59%), 2-ventricle congenital heart disease (44%), and 1-ventricle congenital heart disease (33%). These findings suggest that, although ECMO may be effective for short-term circulatory support, it is not reliable for the long-term circulatory support necessary for children awaiting heart transplantation. Most important, these findings indicate that more effective modalities for long-term circulatory support are urgently needed for children.Conclusions: Although ECMO is effective for short-term circulatory support, it is not reliable for the long-term circulatory support necessary for children awaiting heart transplantation. Fewer than half of patients bridged with ECMO survive to hospital discharge. More effective modalities for chronic circulatory support in children are urgently needed.13FootnotesThe following are highlights from the series, Circulation: Cardiovascular Interventions Topic Review. This series summarizes the most important articles, as selected by the editors, that have published in the Circulation portfolio. The studies included in this article represent the most noteworthy research in congenital heart disease.Correspondence to The Editors, Circulation: Cardiovascular Interventions Editorial Office, 560 Harrison Ave, Suite 502, Boston, MA 02118. E-mail [email protected]