Pediatric catheter interventions: a year in review 2004-2005

PURPOSE OF THE REVIEW: The fields of pediatric and congenital cardiac interventions continue to expand at a rapid pace. The last few years have witnessed a tremendous explosion in procedures such as the transcatheter closure of secundum atrial septal defects, patent foramen ovale, patent ductus arteriosus, stent placement for pulmonary artery stenosis, and coarctation of the aorta. The purpose of this review is to highlight important publications in the last year and the direction the field is taking. RECENT FINDINGS: Research data over the last year has concentrated on six main themes: (a) mid-to-long-term data for device closure of atrial septal defects, the incidence of late cardiac erosions, thrombus formation and heart block; (b) the transcatheter closure of muscular ventricular septal defects; (c) the transcatheter closure of perimembranous ventricular septal defects; (d) the placement of bioprosthetic valves in the pulmonary and aortic positions; (e) the 'hybrid' approach that combines surgical and interventional techniques in the management of various congenital cardiac defects; and (f) fetal interventions. SUMMARY: This review outlines the key data presented in the literature involving interventional cardiology for pediatric and congenital cardiac defects over the last year. It illustrates that in close collaboration with industry, together with bioengineers and cardiothoracic surgeons, adult cardiac interventionists and perinatologists should continue to expand the role of pediatric catheter interventions. Fetal interventions have the potential to alter the natural history of abnormal cardiac development.     

常见先天性心脏病介入治疗进展及争论

先天性心脏病(CHD)的介入治疗近年来取得了很大进展,已成为CHD的一种重要治疗方法。然而目前人们对常见CHD介入治疗仍存在着一些争论。现重点讨论PDA、VSD、肺动脉瓣狭窄、主动脉瓣狭窄等常见CHD介入治疗适应证及方法学等方面的进展及争论。     

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

Whereas the medical advances were reviewed in the previous paper, electro-physiological, 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 hypertrophie 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.     

Interventional cardiac catheterization

Over the past decade, transcatheter interventions have become increasingly important in the treatment of patients with congenital heart lesions. These procedures may be broadly grouped as dilations (e.g., septostomy, valvuloplasty, angioplasty, and endovascular stenting) or as closures (e.g., vascular embolization and device closure of defects). Balloon valvuloplasty has become the treatment of choice for patients in all age groups with simple valvar pulmonic stenosis and, although not curative, seems at least comparable to surgery for congenital aortic stenosis in newborns to young adults. Balloon angioplasty is successfully applied to a wide range of aortic, pulmonary artery, and venous stenoses. Stents are useful in dilating lesions of which the intrinsic elasticity results in vessel recoil after balloon dilation alone. Catheter-delivered coils are used to embolize a wide range of arterial, venous, and prosthetic vascular connections. Although some devices remain investigational, they have been successfully used for closure of many arterial ducts and atrial and ventricular septal defects. In the therapy for patients with complex CHD, best results may be achieved by combining cardiac surgery with interventional catheterization. The cooperation among interventional cardiologists and cardiac surgeons was highlighted in a report of an algorithm to manage patients with tetralogy of Fallot or pulmonary atresia with diminutive pulmonary arteries, involving balloon dilation, coil embolization of collaterals, and intraoperative stent placement. In this setting, well-planned catheterization procedures have an important role in reducing the overall number of procedures that patients may require over a lifetime, with improved outcomes.     

Interventional pediatric cardiology: State of the art and future perspective

Interventional catheter therapy has drastically changed the practice of cardiac catheterization and the treatment of congenital heart disease. In some centers, interventions amount to 30% or more of all cardiac catheterizations. For some lesions, surgery has become obsolete. For valvular pulmonary stenosis, balloon dilatation is the therapy of choice and results in permanent elimination of pressure gradients. Balloon dilatation is also indicated for valvular aortic stenosis and results in mild residual stenosis with gradients below 35 mmHg. Aortic insufficiency, mostly mild, is induced in 15%–20%. Native and post-operative coarctation can be successfully dilated. About 50% of pulmonary artery stenoses can be relieved by balloon dilatation. Stent placement increases the success rate to 75%–80%. Stent implantation is also being investigated for other lesions. Valvular pulmonary atresia can be opened by catheter technique. In the majority of patients over 6 kg, the patent ductus arteriosus is transvenously closed by implantation of the Rashkind occluder. Secundum or similar atrial septal defects and muscular ventricular septal defects can also be closed by catheter technique, but suitable specific occluders are not generally available at present. Therapeutic vascular occlusions, radiofrequency ablation of aberrant conduction pathways and arrhythmia foci are examples of other catheter interventions.     

Overview of interventional pediatric cardiology in 2004

Pediatric interventional catheterization is an expanding specialty with a range of mature, emerging, and investigative procedures and technologies. Many dysfunctional obstructions and/or shunts caused by congenital heart defects may be treated or significantly palliated in the catheterization laboratory. These include valvar pulmonary or aortic stenosis, the patent ductus arteriosus, coarctation of the aorta, branch pulmonary stenosis, atrial septal defects and even ventricular septal defects. Valve replacement technology, approaches to complex heart diseases such as single ventricle, and fetal interventions are subjects of active investigations. A comprehensive review of the present and future of interventional pediatric cardiology is presented.     

Combined Treatment for Multiple Cardiac Defects with Interventional Techniques

Multiple congenital cardiac defects are usually addressed by cardiac surgery. We present our experience with simultaneous transcatheter treatment of multiple defects in children. Ten children, six females and four males, with multiple defects underwent treatment with interventional technique. The mean age was 4.4 +/- 2.6 years (range, 7 months to 8 years). The cardiac diagnosis was patent ductus arteriosus (PDA) and valvular pulmonary stenosis (PS) in two, atrial septal defect (ASD) and PDA in two, ASD and PS in two, PDA and aortic stenosis (AS) in three (severe left ventricular dysfunction in two), and perimembranous ventricular septal defect (VSD) and valvular PS in one. The ASDs were closed with an Amplatzer septal occluder (mean size, 16 +/- 4 mm), four PDAs were closed with an Amplatzer duct occluder, and three with a Cook's detectable coil. Mean balloon size used to dilate the pulmonary valve was 18 +/- 4 mm, and for the aortic valve this was 12 +/- 2 mm. There was a 70% (+/-15%) postprocedure reduction of gradients across the stenotic valves. The closure rate was 75% for PDAs in the catheterization laboratory, 80% for ASDs, and there was a mild residual intradevice leak in the VSD. In conclusion, interventional technology addressing multiple congenital cardiac defects as a combined procedure in the catheterization laboratory is safe and effective.     

Non surgical treatment in congenital heart disease

Dilation of blood vessels transluminally was demonstrated by Dr Andreas Gruntzig in 1978. In 1982, Kan demonstrated that congenitally stenosed valve can be dilated with the use of cylindrical balloon and opened up new vistas in the non-surgical treatment of congenital heart lesions. Rapid progress has been now made in (1) Understanding of mechanism of success or failure of balloon dilation (2) Development of newer hardwares like low profile balloon, high pressure ballons, extra support wires which have contributed to increase in success rate of the procedures (3) Understanding the unnatural history of various congenital heart lesions from the vast data bank of Registries of balloon dilation. As a consequence balloon dilation has become the first procedure of choice in the treatment of valvar pulmonary stenosis and post surgical recurrent coarctation. Although an essentially palliative procedure for the treatment of valvar aortic stenosis and native coarctation beyond the neonatal period, non-randomised studies have shown results similar to that of surgical correction. Balloon dilation of pulmonary artery, pulmonary vein, venous baffles stenosis have shown poor overall results. Balloon dilation for sub-pulmonary stenosis like tetralogy of Fallot is controversial. The development of stents to keep dilated vessel open has also found a place in treatment of congenital heart lesions. Thus pulmonary artery stenosis, recurrent coarctation in adults, venous baffle obstruction, conduit stenosis which respond poorly to balloon dilation alone have shown promising early and mid term results with stents. The use of stents to keep the ductus open, recurrent coarctation in children, in right ventricular outflow tract obstruction is controversial. Development of devices to achieve closure of cardiac defects is relatively new. Patent arterial duct was the first defect to be closed with the help of devices and has shown good results on long term follow up. Recently stainless steel coils have been used to close dose small ducti (up to 3 mm) with very promising medium term results. Its use has also been extended to larger ducti (up to 7 mm). Devices used for closing atrial septal defects, ventricular septal defects are undergoing rapid development. In atrial septal defects its use is restricted to small defects in the fossa ovalis area and in day for atrial septal closure are relatively new and await long term results. The results achieved by non surgical treatment for many congenital heart lesions are essentially palliative and may require repeat interventions at some point in the unnatural history which increases the cost of treatment substantially. The reuse of balloons, guide wires in developing countries helps reduce the overall cost of the procedure.     

Consensus on Timing of Intervention for Common Congenital Heart Diseases: Part I - Acyanotic Heart Defects

The purpose of this review/editorial is to discuss how and when to treat the most common acyanotic congenital heart defects (CHD); the discussion of cyanotic heart defects will be presented in a subsequent editorial. By and large, the indications and timing of intervention are decided by the severity of the lesion. Balloon pulmonary valvuloplasty is the treatment of choice for valvar pulmonary stenosis and the indication for intervention is peak-to-peak systolic pressure gradient >50 mmHg across the pulmonary valve. For aortic valve stenosis, balloon aortic valvuloplasty appears to be the first therapeutic procedure of choice; the indications for balloon dilatation of aortic valve are peak-to-peak systolic pressure gradient across the aortic valve in excess of 70 mmHg irrespective of the symptoms or a gradient ≥50 mmHg with either symptoms or electrocardiographic ST-T wave changes indicative of myocardial perfusion abnormality. The indications for intervention in coarctation of the aorta are significant hypertension and/or congestive heart failure along with a pressure gradient in excess of 20 mmHg across the coarctation; the type of intervention varies with age at presentation and the anatomy of coarctation: surgical intervention for neonates and young infants, balloon angioplasty for discrete native coarctation in children, and stents in adolescents and adults. Long segment coarctations or those associated with hypoplasia of the isthmus or transverse aortic arch require surgical treatment in younger children and stents in adolescents and adults. For post-surgical aortic recoarctation, balloon angioplasty in young children and stents in adolescents and adults are treatment options. Transcatheter closure methods are currently preferred for ostium secundum atrial septal defects (ASDs); the indications for occlusion are right ventricular volume overload by echocardiogram. Ostium primum, sinus venosus and coronary sinus ASDs require surgical closure. For all ASDs elective closure around age 4 to 5 y is recommended or as and when detected beyond that age. For the more common perimembraneous ventricular septal defects (VSDs) of large size, surgical closure should be performed prior to 6 to 12 mo of age. Muscular VSDs may be closed with devices. Patent ductus arteriosus (PDA) may be closed with Amplatzer Duct Occluder if they are moderate to large and Gianturco coils if they are small. Surgical and video-thoracoscopic closure are the available options at some centers. In the presence of pulmonary hypertension appropriate testing to determine suitability for closure should be undertaken. The treatment of acyanotic CHD with currently available medical, transcatheter and surgical methods is feasible, safe and effective and should be performed at an appropriate age in order to prevent damage to cardiovascular structures.     

Normality of cardiopulmonary capacity in children operated on to correct congenital heart defects

BACKGROUND: One of the main goals of corrective surgery of congenital heart defects in children is the improvement of quality of life, which in young children is predominantly determined by exercise capacity. It is not known whether this goal can be achieved in school-aged children who have undergone cardiac surgery in infancy. OBJECTIVES: To determine if primary school-aged children who underwent surgery to correct congenital heart defects in infancy are physically as fit as their peers. METHODS: We examined 84 children with congenital heart defects, aged 4 to 11 years, after surgical repair. Fifty-two children had simple defects (ie, atrial or ventricular septal defect, coarctation of the aorta). Thirty-two children had complex defects (ie, tetralogy of Fallot, pulmonary atresia with ventricular septal defect). All patients underwent exercise testing performed on a specially modified bicycle ergometer. Ninety-eight sex- and age-matched healthy children served as the control group. RESULTS: There was no gender difference, either in healthy children or in the group with congenital heart defects, regarding exercise testing and that the healthy children reached a mean +/- SD normalized maximal performance of 2.8 +/- 0.3 W/kg. The same range was found for the children who had undergone surgery to correct simple heart defects. The children operated on to correct complex heart defects showed significantly impaired mean normalized maximal performance, although this tended to be lower in the group that had pulmonary atresia with a ventricular septal defect than in the group with tetralogy of Fallot (mean normalized maximal performance, 1.9 W/kg vs 2.3 W/kg). CONCLUSIONS: The goal of normal exercise capacity in childhood after heart surgery is achieved in those with simple heart defects only. In children with complex heart defects impaired exercise performance persists, depending on the severity of the heart defect and probably on chronotropic incompetence.     

Spectrum of congenital heart defects in Croatia

The aim of our study was to investigate the incidence of congenital defects in children born in Croatia during a period of 5 years, its association with extracardiac malformations, its treatment, and outcome. Medical information about the patients was obtained from 14 paediatric cardiology centres that cover the whole country. Diagnosis was made by clinical findings, electrocardiography, chest X-ray, echocardiography, catheterisation, or autopsy. Between October 1, 2002 and October 1, 2007, there were 205,051 live births in Croatia, 1,480 of which were patients diagnosed with congenital heart disease, accounting for 0.72% of the live-born children. The distribution was made up of 34.6% children with ventricular septal defect, 15.9% with atrial septal defect, 9.8% with patency of arterial duct, 4.9% with pulmonary valvar stenosis, 3.3% with tetralogy of Fallot, 3.3% with transposed great arteries, 3.3% with aortic stenosis, 3.2% with aortic coarctation, 4.3% with atrioventricular septal defect and common atrioventricular orifice, 2.3% with hypoplastic left heart syndrome, and 8.3% other with severe defects. The average age in the time of diagnoses is 70.41 days (SD, 188.13), with low average time of diagnoses of severe heart defects, 9.6 days (SD, 32.52). Among patients, 14.5% had chromosomal defects, syndromes, and/or other congenital major anomalies. During the study, 57 patients died because of cardiac anomalies or other related problems, 24 who died were operated. The rates of specific cardiac defects and association with extracardiac malformations are generally comparable with those reported in similar studies. In spite of all problems, mortality rate of 3.85% is low but could be improved.     

Risk of pulmonary tuberculosis in children with congenital heart disease

Children with low-flow congenital heart lesions are reported to have an increased incidence of pulmonary tuberculosis. The aim of this study was to investigate if children with congenital heart disease have an increased incidence of pulmonary tuberculosis and to determine if patients with certain heart conditions are more susceptible to pulmonary tuberculosis than others. This retrospective study over a 6-year period showed that pulmonary tuberculosis was 2.5-fold more common in children with congenital heart disease than in normal children from the same community. Children with congenital pulmonary stenosis had a prevalence equal to those with acyanotic (ventricular and atrial septal defects) and cyanotic (transposition of the great arteries) high-flow heart lesions, whereas there were no cases of tuberculosis in children with low-flow cyanotic heart lesions such as tetralogy of Fallot. Cardiac surgery had to be postponed as a result of pulmonary tuberculosis in 7.2% of all patients in whom it was required. Over the 6-year period of the study, cardiac surgery had to be delayed in 60% of cases with pulmonary tuberculosis and congenital heart lesions so antituberculosis therapy could be completed. Physicians treating children with congenital heart lesions should maintain a high index of suspicion for the development of pulmonary tuberculosis, especially in those with acyanotic and cyanotic high-flow lesions and pulmonary stenosis.     

Percutaneous device closure of atrial septal defect in a premature infant with rapid improvement in pulmonary status

Atrial septal defects are a common congenital heart defect and may complicate the course of a premature infant by imposing volume overload to the lungs. Surgical closure requires cardiopulmonary bypass and, frequently, a midline sternotomy. Recently, percutaneous transcatheter devices were approved for atrial septal defect closure but have been limited to use in larger children. Here we present the first known report of a transcatheter device closure of an atrial septal defect in a premature infant, which resulted in rapid improvement of the patient's respiratory status.     

先天性心脏病复合畸形的介入治疗

目的探讨介入治疗小儿先天性心脏病(CHD)复合畸形的可行性和疗效。方法对CHD复合畸形患儿10例施行联合介入治疗,其中房间隔缺损(ASD)并肺动脉瓣狭窄(PS)2例,室间隔缺损(VSD)并动脉导管未闭(PDA)4例,PDA并PS 2例,ASD并PDA 2例。结果7例1次治疗成功,余3例中2例分2次治疗,1例8个月患儿,因其在最初0.5年随访中发现VSD明显缩小,故先封堵了PDA,目前正在随访中。成功率100%,无严重并发症。经1个月-3年随访,患儿心脏缩小,心脏功能改善。结论在病例选择恰当情况下,对小儿CHD复合畸形进行介入治疗是安全、可行的。     

先天性心脏病经导管介入治疗现状及进展

先天性心血管疾病的经导管介入治疗近年得到了长足的发展,介入治疗的方法不断增加,范围不断扩大.文章简要回顾小儿先心病经导管介入治疗的方法如球囊扩张成彤术治疗主动脉、肺动脉及其分支狭窄以及主动脉瓣和主动脉弓缩窄,血管内支架在肺动脉分支狭窄、体静脉狭窄、主动脉缩窄及在未闭动脉导管中的植入以及房、室间隔缺损的介入治疗等,同时介绍最新的一些研究进展,如经皮二尖瓣修复术、主动脉和肺动脉带瓣支架植入及外科手术中的介入治疗(内外科镶嵌治疗)等.     

Congenital heart disease in 111 225 births in Belgium: birth prevalence, treatment and survival in the 21st century

Aim: To investigate the birth prevalence, treatment modalities and short-term survival of children with congenital heart disease who were born in 2002.
Methods: We undertook a retrospective review of medical records of all patients who were born in 2002, and were diagnosed, treated and/or followed-up in one of the seven-paediatric cardiology programmes in Belgium.
Results: In 111 225 births, 921 children with congenital heart disease were detected, yielding a birth prevalence of 8.3 per 1000. The most frequently occurring conditions were ventricular septal defects (VSDs) (33%), ostium secundum atrial septal defects (18%) and pulmonary valve abnormalities (10%). Thirty-nine percent of the children either had a cardiosurgical operation or catheter intervention. In this study, 4% of the children died. The actuarial survival at 6 months and 1 year of age was 97% and 96%, respectively and remained stable after then. Compared to other heart defects, mortality was higher in univentricular physiology, pulmonary atresia with VSD, left ventricle outflow obstruction and tetralogy of Fallot.
Conclusion: Survival of congenital heart disease is excellent and continued to improve in the early 21st century. New therapeutic options are increasingly used. This study provides baseline data for the longitudinal follow-up of this cohort.     

Balloon dilation catheters

Catheter therapy has gained an important role in the treatment of congenital heart disease. The cumulative experience with vascular and valvular balloon dilations has demonstrated low mortality and morbidity with short-term results similar to surgery. Currently, balloon dilation is an accepted treatment for valvular pulmonary stenosis, distal pulmonary artery stenosis, recurrent coarctation, rheumatic mitral stenosis, congenital valvular aortic stenosis, and intra-atrial baffle obstruction. Except for patients at high surgical risk, balloon dilation of native coarctation is considered investigational at most institutions but accepted at others. No conclusive evaluation is yet possible for dilation of bioprosthetic valves and membranous subaortic stenosis. Individual pulmonary veins appear undilatable. Various devices are available for closure of extra- and intracardiac communications. Transcatheter closure of aortopulmonary collaterals and arteriovenous malformations is now well established at some centers. In selected patients, therapeutic embolization of surgical shunts can replace surgery. Transcatheter closure of the patent ductus arteriosus has become routine at some centers. Nonsurgical closure of atrial and ventricular septal defects has entered clinical trials, and preliminary results appear very promising. Blade atrioseptostomy and foreign body retrieval are well established. Improvement of existing procedures and implementation of new concepts will consolidate the role of catheter therapy in congenital and acquired heart disease.     

Transcatheter Closure of Patent Ductus Arteriosus and Atrial Septal Defect Without On-Site Surgical Backup: A Two-Year Experience in an African Community

Congenital heart disease contributes significantly to the health burden of children in Nigeria. Interventions for congenital heart disease have been available in the developed world since the first report on device closure of patent ductus arteriosus (PDA) in 1967 by Porstmann. However, this did not start in Nigeria until October 2010. This study aimed to document the profiles of the patients who had undergone interventions for congenital heart diseases since the availability of the procedure, the challenges encountered, and the prospects associated with the interventions at the study site. All the patients referred to undergo interventions for congenital heart disease at the study center between October 2010 and 2012 were studied. The profile of the patient, including diagnosis at referral, indication for interventions, and interventions performed, were documented. The patients ranged in age from 3 to 62 years (mean age, 13.54 ± 17.7 years), and the male-to-female ratio was 1:3. The diagnosis at referral included PDA in 10 (83 %) of the 12 patients and secundum atrial septal defect in 2 patients (17 %). They all had transcatheter closure of the defects. Interventional procedures for congenital heart diseases currently are available locally, but the high degree of manpower training required, the cost, and the local availability of consumables are major factors limiting their use. Regional and international collaboration could be mutually beneficial.     

Congenital heart disease in Nigeria: a ten-year experience at UCH, Ibadan

Of 880 patients who attended the paediatric cardiology unit, University College Hospital, Ibadan, during a ten-year period, 635 (72.2%) had congenital cardiac malformations. Ventricular septal defects were the commonest lesions (35% of the 635 cases), followed by patent ductus arteriosus (22%), Fallot's tetralogy (10%), pulmonary stenosis (9%) and atrial septal defects (7.5%). Coarctation of the aorta was uncommon (2%) and aortic stenosis rare (0.6%). The overall sex incidence was even. Aetiological factors were ascertained in 72 cases (11%). In 60% of these cases intra-uterine rubella was responsible and in 18% perinatal asphyxia. In most patients the cardiac malformation was detected late; consequently complications, such as heart failure, pulmonary hypertension, and polycythaemia were common, even in new patients. Sixty-seven patients (11%) died in hospital, mostly from surgical intervention, heart failure, hypoxaemia, bronchopneumonia and associated extracardiac defects. It is suspected that hypocalcaemia, resulting from vitamin D deficiency may be a cause of the observed low prevalence of obstructive aortic lesions. We suggest that cardiac evaluation be performed at birth in postnatal clinics and in immunization centres, in order to facilitate early detection and treatment of congenital heart disease.