Balloon aortic valvoplasty in paediatric patients: progressive aortic regurgitation is common.

OBJECTIVE: To evaluate immediate and midterm results after balloon valvoplasty in a paediatric population with congenital aortic stenosis, giving special consideration to aortic regurgitation. DESIGN: Retrospective study. SETTING: Two tertiary referral centres for paediatric cardiology. PATIENTS: 70 consecutive patients, with an age range of 0-16.4 years. Group A infants < 3 months old (n = 21). Group B children > 3 months old (n = 49). Median follow up time was 19.8 months, range 0-158 months. INTERVENTION: All patients underwent balloon aortic valvoplasty. The balloon to annulus ratio was selected at a mean of 0.90 (range 0.67-1.0). MAIN OUTCOME MEASURES: Doppler gradients and degree of aortic regurgitation. RESULTS: The pressure gradient dropped significantly with the intervention and increased mildly at follow up. Freedom from relevant aortic regurgitation (that is, moderate and severe) was initially lower in group A (75% v 90% after one month) but after two years the difference between the two groups was not significant (50% v 61%). Freedom from reintervention was significantly lower in group A (with 35% v 80%) after three years. CONCLUSION: Aortic balloon valvoplasty is safe and effective but has a high rate of early reintervention in infants with critical aortic stenosis. The major long term problem is progressive aortic regurgitation, which does not seem to be prevented by the use of small balloons.

Long-term follow up of children with congenital complete atrioventricular block and the impact of pacemaker therapy.

AIMS: This study assessed survival, morbidity and impact of pacemaker (PM) therapy in children with Congenital Complete Atrioventricular Block (CCAVB). METHODS AND RESULTS: Data of 32 children, diagnosed as showing CCAVB at a median age of 0.4 years (range foetal-10 years), were retrospectively analysed. For comparison of clinical data patients were separated into two groups: CCAVB without structural heart disease (group 1; n = 23) and with structural heart disease (group 2; n = 9). Median follow-up time was 10.2 years. Pacemakers (PM) were implanted in 17 group 1 and all group 2 children. Frequency of PM therapy, age and symptoms before PM implantation did not differ significantly between the groups. Indications for PM implantation were bradycardia in 15, decreased exercise tolerance in 6, syncope in 3 and heart failure in 2 children. PM system related complications occurred in 11/26 (42%) children. Although 1 child died due to PM exit block no further CCAVB related symptoms were recorded in children with PM. CONCLUSION: PM therapy reduces mortality and morbidity in children with CCAVB when compared with natural history data. Although children with PM are free from CCAVB related symptoms limited morbidity remains due to PM system related complications.

Transcatheter occlusion of the patent ductus arteriosus with a single device technique: comparison between the Cook detachable coil and the Rashkind umbrella device.

UNLABELLED: Transcatheter coil occlusion of the patent ductus arteriosus (PDA) has become the interventional treatment option of choice. Immediate occlusion of any residual shunting results in excellent closure rates, but frequently requires multiple coil deployment. AIMS: To assess the efficacy and limitations of single Cook detachable coil PDA closure compared to a preceding series of Rashkind umbrella procedures. METHODS AND RESULTS: Between 1990 and 1999, transcatheter occlusion of a small (<2 mm; n=45) or moderate-sized (2-4 mm; n=47) PDA was successfully attempted in 90/92 consecutive patients (mean age 6+/-4.8 years) with a coil (39/41) or Rashkind device (51/51). Immediate angiographic closure rates for both devices were low, although better for small (54-68%) than moderate ducts (7-22%, P<0.01). A 2-year echocardiographic closure rate of small ducts increased to 92% for the coil group versus 95% for the Rashkind group. By that time, moderate-sized ducts were only occluded in 64% with the coil and 54% with the Rashkind device. A visible residual shunt at post-implant angiography in moderate ducts was associated with a high incidence (59%) of long-term echocardiographic shunt patency and a need for repeat interventions for audible residual shunts (32%). CONCLUSIONS: Single coil transcatheter occlusion is the treatment of choice for the small duct as most residual shunts will resolve spontaneously. However, long-term shunt persistence after single coil deployment in moderate sized ducts is as frequent as with the Rashkind device. A primary multiple coil approach is advocated if the postcoil aortogram shows residual ductal shunting and if there is persistence of a ductal murmur on auscultation.

[Fetal and genetic aspects of congenital heart disease]. / Pränatale und genetische Aspekte angeborener Herzerkrankungen.

Fetal cardiology includes the assessment of the fetal heart for congenital heart disease (CHD) and arrhythmias, the management of affected fetuses, including parental counselling for the therapeutic options, the planning of the delivery and the postnatal care. This requires a close collaboration between obstetricians, neonatologists and pediatric cardiologists. Because of restricted financial sources extensive fetal echocardiographic assessment is reserved for pregnancies with increased risk for CHD, which includes a family history of CHD, suspicion of a cardiac or extracardiac fetal abnormalities at obstetric routine ultrasonography, fetal arrhythmias and chromosomal anomalies. Since most CHD occur in pregnancies without increased risk an ultrasound screening of the fetal heart during routine pregnancy ultrasound is recommended. Most forms of CHD can potentially be detected in utero, especially the severe ones with considerable fetal and postnatal morbidity and mortality. The prenatal diagnosis of a major cardiac malformation requires further assessments for extracardiac and chromosomal disorders. The deliveries of patients with major cardiac anomalies in a tertiary obstetric center close to a pediatric cardiac facility allows optimal perinatal and postnatal management. This may be of crucial importance for cardiac malformations which are arterial duct dependent postnatally. Many CHD have genetic causes. Well established is the association of CHD and the trisomies 13, 18 and 21, as well as the monosomy XO (Turner syndrome). During the last years more and more molecular genetic causes for CHD could be demonstrated. The most significant one is the microdeletion 22q11 syndrome (CATCH 22 syndrome), which is associated with different conotruncal anomalies. Also for various other congenital cardiac malformations and syndromes a genetic cause could be demonstrated. The search for genetic cofactors is important as it affects parental counselling and patient care.

[Maternal cardiac arrhythmias in pregnancy]. / Mütterliche Herzrhythmusstörungen während der Schwangerschaft.

During pregnancy an increased incidence of maternal cardiac arrhythmias is observed. These include a wide spectrum, from clinically irrelevant isolated premature beats to debilitating supraventricular and ventricular tachycardias. In principle, management of arrhythmias during pregnancy is similar to that in non-pregnant patients. However, special consideration should be given to foetal age and potential teratogenic and haemodynamic adverse drug effects on the foetus. Therapeutic strategy should be guided by interdisciplinary consulting (i.e. cardiology, obstetrics, neonatology). Diagnostic evaluation must rule out underlying cardiovascular, pulmonary, endocrine or metabolic diseases. Additionally, precipitating factors such as excessive caffeine and/or alcohol ingestion and cigarette smoking should be avoided. For benign arrhythmias a conservative approach is appropriate. Antiarrhythmic drug selection depends on the specific arrhythmia being treated and the cardiac condition of the mother and the foetus. Some antiarrhythmic agents, such as propranolol, metoprolol, digoxin and quinidine, have been extensively tested during pregnancy and have proven to be safe; they should therefore, whenever possible, be used as firstline. For supraventricular tachycardia, intravenous adenosine may be used to terminate the arrhythmia if vagal manoeuvres fail. In emergency situations cardioversion may be performed with relative safety. Implantable cardioverter defibrillators as a preventive measure for life-threatening arrhythmias in pregnant patients do not seem to increase the risk of major complications.

Recent experience with the arterial switch operation in transposition of the great arteries.

OBJECTIVE: Review of our experience with the technically demanding arterial switch operation in transposition of the great arteries in children. METHODS: Twenty-seven children who underwent an arterial switch operation in our clinic were retrospectively reviewed. Except for one child (operated on at eight months), the operation was performed during the neonatal period. The underlying pathology was d-transposition of the great arteries in 25 children and a double outlet right ventricle of transposition type in 2. Five children had an associated ventricular septum defect and 1 aortic isthmus coarctation. The pattern of the coronary arteries was favourable in 18 children, difficult in 7 and dangerous in 3. The operation was performed in cardiopulmonary bypass for repair of the transposition and in a period of deep hypothermic circulatory arrest for repair of the intracardiac defects. RESULTS: One child died perioperatively and 1 postoperatively (operative mortality 7%) from myocardial ischaemia following unsuccessful transfer of a dangerous pattern of coronary arteries. Another child, a low-birth weight baby, died 80 days after the operation from respiratory failure. Postoperative morbidity occurred in 10 patients and medium-term morbidity in 6 patients who presented various degrees of stenosis of a pulmonary artery. During a median follow-up of 18 months no patient required reoperation. The children are asymptomatic and thriving satisfactorily. CONCLUSION: Because it restores the heart physiology, the arterial switch operation is considered the procedure of choice for correction of transposition of the great arteries. The operation involves acceptable mortality and morbidity. Transfer of difficult coronary artery patterns and development of stenosis on the pulmonary arteries remain problematic.

Elongation of confined ferrofluid droplets under applied fields.

Ferrofluids are strongly paramagnetic liquids. We study the behavior of ferrofluid droplets confined between two parallel plates with a weak applied field parallel to the plates. The droplets elongate under the applied field to reduce their demagnetizing energy and reach an equilibrium shape where the magnetic forces balance against the surface tension. This elongation varies logarithmically with aspect ratio of droplet thickness to its original radius, in contrast to the behavior of unconfined droplets. Experimental studies of a ferrofluid-water-surfactant emulsion confirm this prediction.

22q11.2 deletions in a series of patients with non-selective congenital heart defects: incidence, type of defects and parental origin.

Previous studies have indicated a wide spectrum of incidences of 22q11.2 deletions in isolated and syndromic (sporadic or familial) cases of conotruncal heart defects, whereby the detection rate of the deletion varied from 65% in one study to 0 in another. We analysed 110 patients with non-selective syndromic or isolated non-familial congenital heart malformations by fluorescence in situ hybridization (FISH) using the D22S75 DiGeorge chromosome (DGS) region probe. A 22q11.2 microdeletion has been detected in 9/51 (17.6%) syndromic patients. Five were of maternal origin and four of paternal origin. None of the 59 patients with isolated congenital cardiac defect had a 22q11.2 deletion. We compared the cardiac anomalies of our patients with a 22q11.2 deletion with those of previously published series and we describe types of congenital heart defects which appear to be often associated with a 22q11.2 deletion. The ability to detect such types of heart defects and to provide an early diagnosis of 22q11.2 deletion is particularly relevant in very young infants, who often show only very mild expression of the otherwise well-characterized phenotypes of the DiGeorge/velo-cardio-facial syndrome (DG/VCFS).

Neonatal lupus erythematosus with congenital heart block and severe heart failure due to myocarditis and endocardititis of the mitral valve.

We report a case of neonatal lupus erythematosus (NLE) with congenital heart block and severe myocardial failure, which was followed from the 25th week of gestation because of fetal bradycardia. The child was delivered at the 37th week of gestation by elective cesarean section because of echocardiographically documented heart enlargement, pericardial effusion and moderate insufficiency of the mitral and tricuspid valves. In spite of immediate pacing, intubation and supportive treatment, the newborn developed progressive heart failure. Echocardiography showed endocarditis of the mitral valve and diffuse myocarditis. The heart failure resolved under steroid treatment. Our experience supports the early use of steroids in treating myocarditis due to NLE. Intrauterine steroid treatment in the presence of fetal hydrops and congenital heart block is discussed.

Atypical Kawasaki disease with peripheral gangrene and myocardial infarction: therapeutic implications.

We describe a 2-month-old girl with atypical Kawasaki disease (KD) complicated by peripheral gangrene and myocardial infarction. Peripheral ischaemia leading to gangrene is a rare but serious complication of KD in infants younger than 7 months of age. Treatment has been targeted at reducing arterial inflammation, arteriospasm and thrombosis. We report the first patient with incomplete KD and peripheral ischaemia in whom therapy with prostaglandin E1 (PGE1) as vasodilating and antithrombotic agent appeared successful, restoring hand and foot perfusion without significant long-term sequelae. However, PGE1 could have supported development of myocardial infarction by shunting blood away from ischaemic areas distal to a giant coronary artery aneurysm with beginning thrombosis. CONCLUSION. Atypical KD with peripheral gangrene appears to react favourably to treatment with PGE1, but needs careful monitoring to detect early signs of cardiac ischaemia.

Prevention of residual ventricular septal defects with fibrin sealant.

BACKGROUND: Modern echocardiography now allows for the detection of a substantial number of residual ventricular septal defects (VSDs) after surgical patch repair that remained hidden in the past. Mostly without hemodynamic significance, residual VSDs may have clinical consequences (progressive dehiscence, hemolysis, prophylactic antibiotic treatment, endocarditis). To reduce the number and size of residual VSDs we performed an experimental and a clinical study. METHODS: (1) In an experimental setup, burst pressure of 60 fibrin glue-sealed defects (calibrated between 1.0 and 5.0 mm in diameter) was determined using a computerized recording system and pressure loads up to 500 mm Hg. (2) In a prospective clinical trial with blinded postoperative echocardiographic controls VSD closure was performed in 36 consecutive patients (age, 37 +/- 40 months; range, 4 to 134 months) using a polytetrafluoroethylene patch and running sutures reinforced with pledgets (22 of 36 patients) or sealed with fibrin glue (14 of 36 patients) in accordance to the surgeon's preference. RESULTS: (1) Experimentally, mean pressure load achieved was more than 500 +/- 0 mm Hg for 1.0-mm defects, 413 +/- 52 mm Hg for 2.5-mm defects, 363 +/- 58 mm Hg for 4.0-mm defects, and 313 +/- 48 mm Hg for 5.0-mm defects (r 0.873, p < 0.001). (2) Clinically, all patients survived. Residual VSDs at echocardiography were observed in 16 of 22 patients (72%) for reinforced versus 5 of 14 patients (36%) for sealed with fibrin glue (p < 0.05). Diameter of residual VSDs accounted for 1.3 +/- 1.2 mm for reinforced versus 0.3 +/- 0.4 mm for sealed with fibrin glue (p < 0.01). Hemodynamically significant residual VSDs were fond in 2 of 22 patients (9%) for reinforced versus 0 of 14 patients (0%) for sealed with fibrin glue (p = not significant). CONCLUSIONS: Small defects sealed with fibrin glue resist physiologic pressure load. Fibrin glue sealing of prosthetic patches during intracardiac VSD repair allows for significant reduction of number and size of residual VSDs. Improved long-term outcome can be expected.

[Childhood treatment of paroxysmal supraventricular tachycardia using i.v. adenosine]. / Behandlung der paroxysmalen supraventrikulären Tachykardie im Kindesalter mit Adenosin i.v.

Paroxysmal supraventricular tachycardia is the most frequent significant arrhythmia in the pediatric age group, especially in the first year of life. In neonates and infants there are important limitations for the commonly used drugs such as verapamil and digitalis. In an open Swiss multicentre study we treated 19 children with a total of 29 episodes of tachycardia by means of adenosine i.v. as the drug of first choice. 76% of all the tachycardias were converted, whereas the success rate was 87% if only tachycardias with atrioventricular reentry were considered. The important advantage of adenosine lies in its very short half-life of about 15 seconds, which means that the rare relevant, and the more common mild, side effects are quite limited in duration. A major disadvantage are recurrences in about one third of cases. We conclude that adenosine is an efficient and safe treatment for paroxysmal supraventricular tachycardia in the whole pediatric age group including neonates and infants.