Modified hemi-Fontan operation and subsequent nonsurgical Fontan completion

Transcatheter Fontan completion: Creation of an extracardiac Fontan

Patients with functionally univentricular hearts are usually palliated surgically. There have been several reports of successful attempts to complete the Fontan procedure without surgery. The pathways created at the time of the preconditioning were largely reminiscent of the lateral tunnel Fontan. However, this approach is still confidentially limited to a small number of centers. In 2013, we designed a circuit that mimics the actual surgical technique of extracardiac total cavopulmonary connection to allow for transcatheter completion in an animal study. A polytetrafluoroethylene conduit was connected between the pulmonary artery and the inferior vena cava (IVC). The superior anastomosis was occluded to avoid flow between IVC and superior vena cava (SVC). The conduit was connected to the right atrium (RA) and a large fenestration was created to allow free flow from the IVC to the RA. Extrapolating our approach, a center reported the successful transcatheter completion of an extracardiac Fontan in a 6-year-old child. However, this technique is not directly transposable to our population of patients who require preconditioning in infancy. We report here an innovative extension of this technique that may allow preparing patients in infancy, ideally at the time of the Glenn in the future, to receive an extracardiac Fontan at 2 years/11 kg without additional surgery.

Transcatheter interventions in patients with a Fontan circulation: Current practice and future developments

The Fontan operation represents the last of multiple steps that are offered a wide range of congenital cardiac lesions with a single ventricle (SV) physiology. Nowadays this surgical program consists of a total cavopulmonary connection (TCPC), by anastomosing systemic veins to the pulmonary arteries (PAs), excluding the right-sided circulation from the heart. As a result of imaging, surgical, percutaneous, and critical care improvements, survival in this population has steadily increased. However, the Fontan physiology chronically increases systemic venous pressure causing systemic venous congestion and decreased cardiac output, exposing patients to the failure of the Fontan circulation (FC), which is associated with a wide variety of clinical complications such as liver disease, cyanosis, thromboembolism, protein-losing enteropathy (PLE), plastic bronchitis (PB), and renal dysfunction, ultimately resulting in an increased risk of exercise intolerance, arrhythmias, and premature death. The pathophysiology of the failing Fontan is complex and multifactorial; i.e., caused by the single ventricle dysfunction (diastolic/systolic failure, arrhythmias, AV valve regurgitation, etc.) or caused by the specific circulation (conduits, pulmonary vessels, etc.). The treatment is still challenging and may include multiple options and tools. Among the possible options, today, interventional catheterization is a reliable option, through which different procedures can target various failing elements of the FC. In this review, we aim to provide an overview of indications, techniques, and results of transcatheter options to treat cavopulmonary stenosis, collaterals, impaired lymphatic drainage, and the management of the fenestration, as well as to explore the recent advancements and clinical applications of transcatheter cavopulmonary connections, percutaneous valvular treatments, and to discuss the future perspectives of percutaneous therapies in the Fontan population.

Congenital heart disease: Saving lives and securing liveliness with early primary care and expert family care

Pertinent perspectives for practical applications is advantageous professionalism. Congenital heart diseases (CHDs) are of varied types, severity, and complexity. Simple scientific approach along with sophistication is required for successful management at all levels. We gleaned important information from published evidence and authoritative resources and have put things in practical perspective. These include current prevention, care, correction, cure, and rehabilitation strategies for robust practices. Prospective prevention is with preconception counseling and addressing environmental factors. Fetal echocardiography and nondirective genetic counseling are important. Early detection and expert diligence is desirable. The suspicion is clinical. A number of clinical and investigative diagnostic modalities are available and should be utilized as guided by the clinical cues. Medical management includes general health maintenance, immunizations, monitoring, and complications treatment. Pediatric interventional cardiology is making rapid strides and treating many types of lesions. Understanding of procedure done is a prerequisite of follow-up care. Surgery is of curative, reparative, or palliative types. After surgical correction in early childhood long-term sequelae are rare. After reparative surgery some have life-long sequelae and some have significant late impairment. The number of postintervention/surgery survivors into adulthood is increasing. Microsurgical techniques are leading the way for precision and fewer complications. Follow-up care with "Ten Points Information and Action Plan (TP-IAP)" is suggested. The Armed Forces scenario involves frequent movements to difficult and harsh conditions. Special precautions for affected children needed. Cardiovascular health is enhanced by avoiding a sedentary lifestyle and obesity. Various intrinsic and extrinsic factors limiting functioning need to be suitably addressed.

Transcatheter Fontan completion using novel balloon and stent system

Despite advances in percutaneous interventions, transcatheter Fontan completion remains experimental and performed only in select cases. Non-surgical Fontan completion requires surgical preconditioning at an earlier stage of palliation. We describe transcatheter Fontan completion in a 15-year-old male with previously failed surgical Fontan palliation without surgical preconditioning.

Transcatheter biventricular conversion in an adult patient with a 1.5 ventricle Glenn palliation and superior vena cava syndrome

Covered stents have a continually expanding spectrum of applications for patients with congenital heart disease. Here we report use of covered stents to successfully perform a first-in-human percutaneous biventricular conversion of a 1.5 ventricle Glenn palliation in an adult born with pulmonary atresia. This case demonstrates that in patients considered borderline for biventricular repair, surgery can potentially be modified to promote growth of underdeveloped structures and setup for transcatheter biventricular conversion.

Hybrid Procedures: A Surgeon's Viewpoint on the Next 10 Years

Many forces are once again bringing the congenital heart surgeon and interventional cardiologist, and the teams that support them, ever closer together in what has been deemed Hybrid Approaches to congenital heart disease. The goal of these hybrid approaches is to improve the quantity and quality of life for the patients we serve.

Recent advances in pediatric interventional cardiology

During the last 10 years, there have been major technological achievements in pediatric interventional cardiology. In addition, there have been several advances in cardiac imaging, especially in 3-dimensional imaging of echocardiography, computed tomography, magnetic resonance imaging, and cineangiography. Therefore, more types of congenital heart diseases can be treated in the cardiac catheter laboratory today than ever before. Furthermore, lesions previously considered resistant to interventional therapies can now be managed with high success rates. The hybrid approach has enabled the overcoming of limitations inherent to percutaneous access, expanding the application of endovascular therapies as adjunct to surgical interventions to improve patient outcomes and minimize invasiveness. Percutaneous pulmonary valve implantation has become a successful alternative therapy. However, most of the current recommendations about pediatric cardiac interventions (including class I recommendations) refer to off-label use of devices, because it is difficult to study the safety and efficacy of catheterization and transcatheter therapy in pediatric cardiac patients. This difficulty arises from the challenge of identifying a control population and the relatively small number of pediatric patients with congenital heart disease. Nevertheless, the pediatric interventional cardiology community has continued to develop less invasive solutions for congenital heart defects to minimize the need for open heart surgery and optimize overall outcomes. In this review, various interventional procedures in patients with congenital heart disease are explored.

Role of stents in congenital heart disease

For more than 10 years, balloon-expandable intravascular stents have become an integral part of treatment for obstructive vascular lesions in children and adults with congenital heart disease. The initial problems with stents, such as sharp edges, rigid frame and unacceptable shortening when over-expanded have been overcome to a large extent with the newer designs. The problems related to delivery of stents, such as stent migration, balloon rupture, flaring of the edges of the stent, rupture of vessels and milking of the stent off the balloon, have also been overcome by newer designs of balloons. The failure of growth of balloon-expandable stents with the growth of the child is managed by redilation with or without additional stenting and newer growth stents. Self-expanding stents are not appropriate for use in growing children due to the limitation of their maximum diameters. The development of biodegradable stents may overcome these disadvantages in the future. Various new developments have recently occurred. Covered stents are ideal for treating acute vessel rupture and in isolating vascular aneurysms. Drug-eluting stents may prevent restenosis, but have not been used in children. Valved stents are a recent innovation for the treatment of regurgitant pulmonary valves.

The Fontan Connections: Past, Present, and Future

The Fontan procedure is now considered the final common pathway for patients with anatomical or functional single ventricle. These patients initially have their systemic and pulmonary circulations in parallel, supported by one functional ventricular chamber. The ultimate goal with this procedure is to separate the two circulations, to prevent mixing of venous and arterial blood, and to provide adequate tissue oxygenation. The objective of this article is to review the Fontan procedure with its various modifications and refinements since its introduction to clinical practice in 1971, by Fontan and Baudet.

Alternate method for hybrid Fontan completion

A Fontan completion with a hybrid approach was performed on a 27-month-old girl with a univentricular heart. A large covered stent was placed between the inferior vena cava and the cavopulmonary anastomosis through a pericardial patch in the intracardiac fenestrated tunnel, circumventing the need for an occluder device for baffle closure. The child's progress has been good and she displays normal growth and acceptable clinical, ultrasonographic, and laboratory results.

Diagnosis and management of cyanotic congenital heart disease: part I

Most commonly encountered cyanotic cardiac lesions in children, namely, tetralogy of Fallot, transposition of the great arteries and tricuspid atresia are reviewed. Pathology, pathophysiology, clinical features, non-invasive and invasive laboratory studies and management are discussed. The clinical and non-invasive laboratory features are sufficiently characteristic for making the diagnosis and invasive cardiac catheterization and angiographic studies are not routinely required and are needed either to define features, not clearly defined by non-invasive studies or as a part of catheter-based intervention. Surgical correction or effective palliation can be undertaken with relatively low risk. However, residual defects, some requiring repeat catheter or surgical intervention, are present in a significant percentage of patients and therefore, continued follow-up after surgery is mandatory.

The adult with a Fontan operation

Since 1971, the Fontan operation has been performed for the repair of single-ventricle physiology. This ingenious operation commits a single ventricle to the systemic circulation and takes advantage of cardiovascular and respiratory physiology to propel deoxygenated blood to the lungs, thus minimizing right-to-left shunting and cyanosis. Initially performed as a right atrial to pulmonary artery anastomosis, the Fontan operation has gone through evolutionary steps that have resulted in progressive improvements in mortality, morbidity, and outcomes. Inclusion of the right atrium in the slow-flowing Fontan circuit results in progressive dilation and incessant arrhythmias. This spurred forth efforts to create modifications that partially or completely exclude the atrium from the Fontan circuit. The transcatheter completion of the Fontan operation has been performed in a small number of patients and we expect minimally invasive, transcatheter, and hybrid interventions to play an important role in the future management of these patients.

Fontan completion without surgery

OBJECTIVE

There are several modifications introduced in the preparation for a subsequent non-surgical transcatheter completion of the Fontan procedure. We report our experience with one type of the modification and the short-term results following its implementation.

METHODS

During bidirectional cavopulmonary connection (BCPC) an intra-atrial lateral tunnel is additionally created, as intended for a Fontan procedure but fenestrated with a 10-14 mm aperture. The cardiac end of the superior vena cava (SVC) is then patched to maintain the physiology of BCPC. During the interventional transcatheter completion procedure, the SVC patch is perforated using radio-frequency (RF) energy, balloon-dilated, and stented as well. The aperture is closed with a device when required. Paired t-test was used to compare data before and after the Fontan completion.

RESULTS

From June 2003 to February 2006, 16 patients (9 boys and 7 girls, mean age 12 months) underwent the surgical procedure described. The mean bypass time was 137 min and the mean ischemic time was 77 min. There were no operative deaths. One patient with bilateral SVC required a take down due to recurrent effusions. Ten months later, nine patients underwent completion (mean age 20 months, mean weight 10.6 kg). The stents were dilated to a mean diameter of 14.4mm. All except one aperture was closed with a device. The mean fluoroscopy time was 41 min. Oxygen saturation increased from 85 to 94% (p=0.001). Pulmonary artery pressures remained normal (16 mmHg before and 19 mmHg after, p=0.12). No patients required mechanical ventilation and none developed pleural effusions or arrhythmias. All were discharged from hospital within 6 days of the Fontan completion. Twenty-two months after Fontan, all were well. Echocardiography revealed no gradients across the stents. Two patients had minor leaks across the aperture. One underwent further stent dilatation a year later.

CONCLUSIONS

Fontan completion without surgery is suitable in patients with single ventricles with lower mortality and morbidity, avoids multiple surgical interventions while maintaining the staged approach and allows for successive dilatation of the Fontan pathway to accommodate for growth.

Fontan completion without surgery

An ideal Fontan procedure would minimize complications while maximizing flow dynamics through the circuit. We report our early experience with a new combined surgical/transcatheter approach which enables a nonoperative, transcatheter Fontan completion. The conceptual rationale of this management strategy, as well as surgical and catheterization techniques, are discussed.

Recent advances in pediatric cardiology--electrophysiology, transcatheter and surgical advances

Whereas the medical advances were reviewed in the previous paper, electrophysiological, transcatheter and surgical advances will be the focus in this review. Greater understanding of the arrhythmias, development of non-pharmacological treatment, namely catheter ablation and internal cardioverter-defibrillator (ICD) and miniaturization pacemakers and IDs have occurred in the last decade so that the methods could be applied to smaller and more complex patient population. Surgery has been the traditional treatment option for palliation and correction of congenital and acquired heart defects in infants and children. During the last one to one and one-half decades, a remarkable number of transcatheter methods were developed and refined. These developments during the last decade were reviewed and include long-term results of balloon dilatation procedures, transcatheter closure of atrial septal defects, patent ductus arteriosus, and ventricular septal defect, percutaneous valve replacement, intravascular stents to manage vascular obstructive lesions that can not be satisfactorily balloon-dilated, catheter completion of Fontan procedure, myocardial reduction in hypertrophic cardiomyopathy and other miscellaneous procedures. Recent advances in the transcatheter modes of therapy have added a new dimension to the management of neonates, infants and children with heart disease. They should now be added to the armamentarium available to the Pediatrician and Pediatric Cardiologist in the management of cardiac problems in the pediatric patient. Surgical methods and concepts have been greatly refined such that surgery can be undertaken even in the sickest and most complex patient. The majority of congenital heart defects can be corrected by open heart surgery; some require prior palliation and others can be operated without prior palliation. Recent advances in various defects were reviewed.

Future of interventional cardiology in pediatrics

A trend toward use of less invasive, nonsurgical approaches to the treatment of congenital heart disease has developed. Although transcatheter valve replacements and ventricular septal defect closures have already been performed in children, many other techniques and devices are being developed for the palliation of children with a single ventricle. Several groups have already established catheter-based procedures for the creation of Fontan communications, and others have performed nonsurgical pulmonary artery banding. Additionally, fetal catheter-based interventions are being developed for the treatment of severe congenital heart disease in utero. Because this trend toward catheter-mediated treatment is certain to continue, care must be taken to regulate safely the introduction of novel techniques and devices into clinical use in pediatric cardiology.

Tricuspid Atresia

Untreated, the prognosis for patients with tricuspid atresia (TA) is poor. Recent advances in medical and surgical therapy, particularly the application of Fontan principle, have markedly improved the long-term outlook for children with this condition. Palliative procedures to normalize the pulmonary blood flow and to relieve interatrial or interventricular obstruction should be undertaken promptly. Staged total cavopulmonary connection to bypass the right atrium and right ventricle by an initial bidirectional Glenn procedure and followed by extracardiac conduit diversion of inferior vena caval flow into the pulmonary arteries appears to be the current procedure of choice in the surgical management of TA. Total cavopulmonary diversion appears to be superior to conventional Fontan-Kreutzer operations, but long-term follow-up results are needed to confirm this impression.

Catheter therapy for fontan baffle obstruction and leak, using an endovascular covered stent

A 6 1/2-year-old (weight 20 kg) patient was found to have significant cavo-atrial obstruction and significant right-to-left shunt via multiple large fenestrations in the baffle, with oxygen saturation of 81% 3 1/2 yr after a fenestrated Fontan operation. In one session, this patient had undergone placement of a Palmaz stent at the cavo-atrial narrowing in order to increase anterograde venous return into the pulmonary artery. This was unsuccessful in improving the oxygen saturation because of the large leak in the baffle. Therefore, at a second catheterization session, two telescoping dacron-covered experimental vascular self-expanding stents were placed from the right atrial origin (distal to the hepatic veins) into the pulmonary artery connection delineated by the Palmaz stent, with complete reconstruction of the baffle and improvement in oxygen saturation to 95%.