Delayed recognition of haemodynamically relevant congenital heart disease.

UNLABELLED: Delayed recognition of congenital heart defects may have a serious impact on the long-term outcome of the children affected. It was the aim of the present study, to evaluate the proportion of children with delayed cardiac diagnosis out of a large cohort of consecutive paediatric patients requiring treatment for congenital heart disease. A prospective study was performed over a 3-year period. Of all 323 paediatric patients requiring surgical (n = 291) or catheter interventional (n = 32) treatment for congenital heart disease, patients with delayed diagnosis of their cardiac defects were observed and especially examined for the presence of clinical cardiac findings other than systolic murmurs, not recognized as such prior to referral. Of all the patients, 32 (10%) had delayed diagnosis of heart defects. Surprisingly, the proportion of late diagnoses was not different in the group of patients with cyanotic heart disease where 7/72 patients were referred with delay, compared to 25 delayed referrals among 251 children with acyanotic heart defects. Of the 32 patients with delayed diagnosis, 7 had complications due to delayed referral, but there was no mortality associated with late diagnosis. CONCLUSION: A substantial proportion of all paediatric patients requiring intervention for heart disease were diagnosed with relevant delay. In all study patients with late diagnosis, clinical cardiac findings other than systolic murmurs were present that should have alerted the physician on the possible presence of underlying heart disease.

Pediatric open heart operations without diagnostic cardiac catheterization.

BACKGROUND: Echocardiography allows for an adequate noninvasive preoperative evaluation in an increasing proportion of pediatric patients before open heart operations. The present study assessed the diagnostic accuracy of both invasive and noninvasive preoperative evaluation in children with congenital heart disease. METHODS: We prospectively evaluated the accuracy of preoperative noninvasive or invasive diagnostic methods. Preoperatively established diagnosis was compared with the intraoperative diagnosis made by surgical inspection and routine perioperative transesophageal echocardiography. RESULTS: During the study period of 30 months (ending in December 1997) 209 open-heart procedures were performed. Eighty-one patients (39%) were in the first year of life at the time of surgery, and 43% of all patients had symptoms. Noninvasive preoperative diagnosis using echocardiography was done exclusively in 142 patients (68%). Of the 67 children who had preoperative catheterization, 4 (6%) showed an additional intraoperative finding that modified the surgical approach in 2 of them. In the 142 patients who had echocardiographic preoperative assessment, the surgeons were confronted with a previously undiagnosed finding in 12 patients (8.5%). The finding was considered significant (prolongation of cardiopulmonary bypass time) in 2 patients and might have affected the outcome in 1 of them, a neonate with transposition of the great arteries and a preoperatively undiagnosed intramural coronary artery, who died postoperatively despite a technically adequate repair. CONCLUSIONS: In many infants and children, diagnostic work-up before open heart operations could be adequately based on an exclusively noninvasive basis by relying on echocardiography alone.

Quantitative echocardiographic characterization of abdominal aortic pulsatility in children with coarctation.

Obstructed blood flow due to aortic coarctation leads to a pressure drop and loss of the pulse wave distal to the stenosis. This can be observed by echocardiography as typically decreased pulsatility of the abdominal aorta after cardiac systole. Our study intended to quantitatively describe abnormal abdominal aortic pulsatility in children with coarctation. A standardized M-mode echocardiographic study of the abdominal aorta was prospectively performed with measurements of minimum and maximum abdominal aortic diameters and the corresponding time intervals during the cardiac cycle. Of these measurements the percent increase in aortic diameter was calculated and this increase was indexed to a unit of time. A total of 50 children were studied: 27 had angiographically proven severe coarctation (19 unoperated and 8 operated children with recurrent coarctation) with a mean minimum aortic lumen of 32+/-6% of the prestenotic aortic lumen. A total of 23 healthy children were studied as a control group. Children with significant coarctation differed from normals in all parameters evaluated. Two calculated values, the percent increase in aortic diameter (5-25% in patients and 27-50% in normals) and the percent increase per unit of time (18-108%/s in patients and 154-288%/s in normals) allowed for a clear discrimination between patients and normals with no overlap of individual values. Quantitative characterization of abnormal pulsatility of the abdominal aorta due to the loss of pulse wave pressure clearly discriminated children with angiographically proven significant coarctation from normal controls.

[Atenolol for preventing recurrence of atrioventricular reentry tachycardia in childhood]. / Atenolol zur Rezidivprophylaxe von atrioventrikulären Reentrytachykardien im Kindesalter.

BACKGROUND: Supraventricular reentrant tachycardias are the most common cardiac arrhythmia observed in infancy and childhood. The often benign clinical course of the disease warrants careful selection of any antiarrhythmic drug given to prevent recurrencies, in order to avoid potentially dangerous side-effects such as proarrhythmia. This study reports our experience with atenolol in the longterm treatment of infants and children with supraventricular tachycardias. PATIENTS AND METHODS: A search of our database was made and all the children admitted in our institution between 1987 and 1995 for treatment of supraventricular tachycardia were selected. Patients who had longterm oral treatment with atenolol were retrospectively evaluated and were seen during 1996 in our outpatient clinic for a follow-up examination including a Holter-monitor. RESULTS: 14 infants and children with a median age of 2 9/12 years at first presentation could be evaluated. In 10 patients, atenolol was the first antiarrhythmic drug given. In 10 of the patients (72%) therapy with atenolol was considered successful and no further attacks of tachycardia occurred. In 2 patients a partial response to atenolol was seen with an important decrease in the frequency of tachycardias. Two patients showed no effect of treatment and the betablocker was withdrawn. The effect of the drug on heart rate and blood pressure was mild and did not lead to symptoms. In no case had the drug to be withdrawn for adverse effects. After a mean follow-up of 50 months (3-105 months), 7 patients were off the drug and free of recurrencies while among the 5 children still on atenolol, only one experienced rare episodes of tachycardia. CONCLUSION: Atenolol is efficient in the longterm treatment of supraventricular tachycardias and due to its favorable risk profile can be recommended as first line treatment option.

Results of a restrictive use of antiarrhythmic drugs in the chronic treatment of atrioventricular reentrant tachycardias in infancy and childhood.

Childhood supraventricular tachycardia (SVT) carries a good prognosis. Thus, treatment should be based on the use of drugs with a low risk of such potentially serious side effects as proarrhythmia, which is well documented for class I and III drugs in children. We studied all pediatric patients with a first manifestation of SVT between 1988 and the end of 1995 who were seen for a follow-up examination, including Holter monitoring, during 1996. The minimum follow-up period was 12 months. Fifty children met study entry criteria. Mean patient age at first presentation was 2 years (median 1 month), with 33 of the patients (66%) having experienced their first episode of tachycardia in their first year of life. Of 39 patients initially treated with either digoxin or a beta blocker, SVT in 29 (75%) responded favorably to this treatment. There were no adverse effects. Of the 10 children whose disease did not respond to these first-line agents, 9 (23% of those treated) required class I or III antiarrhythmic drugs. Thus, first-line antiarrhythmic long-term prophylaxis using drugs with a favorable risk profile, such as digoxin and beta blockers, resulted in successful disease management in a large proportion of unselected children, avoiding the need for chronic use of class I or class III antiarrhythmic drugs.

Re-entrant supraventricular tachycardia in infancy: current role of prophylactic digoxin treatment.

UNLABELLED: Re-entrant supraventricular tachycardia is the most common cardiac arrhythmia in infancy. Pharmacological prevention of recurrencies is a standard recommendation for infants less than 1 year of age. In view of the often benign spontaneous clinical course of the disease, the risk-benefit analysis of any antiarrhythmic agent given is important. It was the aim of this retrospective study, to assess the value of oral long-term digoxin given to paediatric patients with supraventricular tachycardia with onset in the first 4 months of life. Twenty-six newborns and infants fulfilled the inclusion criteria. Median age at first presentation of the patients was 7 days. Eight patients (31%) had structural heart disease, 9 patients had a pre-excitation syndrome, and the other 17 children had a concealed accessory atrioventricular pathway. Long-term prophylaxis with oral digoxin was considered successful in 17 children (65%). In 2 patients therapy with digoxin was considered partially effective and in 7 patients (27%) failure of digoxin to improve symptoms led to the introduction of other anti-arrhythmic agents. Serum digoxin levels were no different in the patients with successful therapy as compared to those with treatment failure. No side-effects due to digoxin were noted in all the patients treated. After a mean followup of 54 months (12-130 months), 19 children (73%) were free of recurrencies and on no medication, 5 children were free of recurrencies but had anti-arrhythmic therapy. Only 2 patients, both on anti-arrhythmic therapy, were still suffering from tachycardia. CONCLUSION: Digoxin remains an effective treatment option in infants with supraventricular tachycardia and it helped to avoid the long-term use of other anti-arrhythmic drugs with potentially more serious side-effects (pro-arrhythmia) in a considerable proportion of infants treated.

Comparison of troponin-I and troponin-T after pediatric cardiovascular operation.

BACKGROUND: Although the diagnostic value of troponin-T in childhood is documented, little is known about the significance of troponin-I. It was the aim of this study to compare the diagnostic value of troponin-I and troponin-T in children and newborns to assess the perioperative potential myocardial damage. METHODS: Forty-eight children, mean, 51+/-54 months (mean value +/-1 standard deviation) (range, 1 day to 204 months) undergoing cardiac operation were prospectively enrolled in the present study. Troponin-I, troponin-T, creatine kinase (CK), and the MB isoenzyme were measured before operation and postoperatively within 2 days. RESULTS: Postoperative values of troponin-I for children undergoing extracardiac operation were in the normal range. In children with interventions through the right atrium (n = 10) the mean value increase to 6.5+/-6.1 microg/L (range, 1.8 to 24.3 microg/L) and even to a mean of 29.9+/-21.1 microg/L (range, 7.5 to 90 microg/L) (p<0.01) in children with atrial and additional ventricular surgical approach (n = 23). Troponin-I was of equal specificity and sensitivity compared to troponin-T, excepted in patients with postoperative renal failure in whom troponin-T raised to false pathological results. CONCLUSIONS: For detection of perioperative myocardial damage troponin-I shows a higher specificity than CK-MB activity and CK-MB mass. The diagnostic value of troponin-I is similar to troponin-T, but compared with troponin-T, it has the advantage of not being influenced by renal failure.

Familial hypercholesterolaemia with severe cardiac involvement in a boy: successful management and mid-term follow-up.

A 13-year-old boy with double heterozygosity for familial hypercholesterolaemia with a 90% left coronary artery main stem stenosis is reported. The patient's cholesterol levels were effectively controlled with weekly sessions of selective low-density lipoprotein cholesterol removal through immunoadsorption by use of an extracorporeal system. Left main coronary artery stenosis was successfully treated with percutaneous transluminal balloon dilation. At 30 months after the intervention and still under treatment with weekly sessions of low-density lipoprotein apheresis the patient is free of cardiac symptoms. He shows normal exercise capacity and normal myocardial perfusion. It is concluded that aggressive management is justified in such patients and may result in a near-normal quality of life.

Cardiac arrhythmias mimicking primary neurological disorders: a difficult diagnostic situation.

Cardiac arrhythmias can present with the signs and symptoms of a seizure disorder. This potentially life-threatening underlying cause of non-febrile seizures should be recognized early, since successful specific treatment is possible. The purpose of this retrospective study was to examine common features in such patients. Over a period of 25 years, eight patients were initially treated for up to 5 years at our institution for a seizure disorder until dysrhythmia as the underlying cause of the seizures was disclosed. The main symptom was drop attacks coinciding with physical activity or emotional stress. Convulsions were only rarely observed. In five of the eight patients the underlying disorder was the long-QT-syndrome (Romano-Ward syndrome). In one patient intermittent complete atrioventricular block was found, another patient showed ventricular tachydysrhythmia of unknown etiology and the last patient suffered from hypertrophic cardiomyopathy.

[Therapeutic efficacy and diagnostic potential of adenosine in infants and children]. / Therapeutischer Nutzen und diagnostische Möglichkeiten von Adenosin bei Säuglingen und Kindern.

In an open study a total of 53 episodes of supraventricular reentrant tachycardia in 31 infants and children were treated with intravenous adenosine at two centers. Adenosine was given as a rapid intravenous bolus injection beginning with a dose of 0.1 mg/kg. If there was persistence of the dysrhythmia dosage was increased in 0.05 mg/kg-steps up to a maximum dose of 0.3 mg/kg if necessary. The median dose required for successful termination of the tachycardias was 0.15 mg/kg. In 26 patients with 48 episodes of regular narrow-QRS-complex tachycardia adenosine was used as the therapeutic agent of first choice. In all patients a shortlasting atrioventricular block occurred within seconds after the administration of adenosine. In 42 of 48 episodes of tachycardia (87%) the dysrhythmias were converted to a stable sinus rhythm. In six episodes (13%) recurrence of the tachycardia was observed immediately. In five children adenosine was used for diagnostic purpose: in three children with wide-QRS-complex tachycardia successful termination with adenosine proved the supraventricular origin of the dysrhythmia. In two children with suspected atrial flutter adenosine-induced atrioventricular block allowed identification of flutter waves in one patient while in the other patient no effect of adenosine was seen. Side-effects such as flush, chest-pain or abdominal pain were frequent but mild and only of a few seconds' duration. No influence of adenosine on blood pressure was noted. Only in one child with previously unknown sinus node dysfunction was a relevant electrophysiologic side effect seen: a prolonged sinus arrest with asystole of 12 seconds' duration occurred after adenosine administration.(ABSTRACT TRUNCATED AT 250 WORDS)

[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.

Stress-induced polymorphous ventricular tachyarrhythmias in two brothers: unusual pattern of inheritance in the long QT syndrome.

Two brothers, 10 and 9 years old, are reported who were treated for years with antiepileptic drugs until the cardiac origin of their syncopal attacks was discovered. Our findings are consistent with the diagnosis of long QT syndrome, although no other family members are affected and only intermittent and mostly borderline QT prolongation could be found. Diagnostic difficulties and genetic implications are discussed.

Left main coronary angioplasty in a 10-year-old boy with homozygous familial hypercholesterolemia.

Homozygous familial hypercholesterolemia is a rare cause of premature coronary artery disease. A young boy with this disorder who underwent successful coronary angioplasty for left main stem stenosis is presented.

[Energy metabolism of the brain, detected with 31-P magnetic resonance spectroscopy during extracorporeal circulation in the rabbit]. / Energiestoffwechsel des Hirns, erfasst mit 31-P Magnet-Resonanz-Spektroskopie während des extrakorporalen Kreislaufes beim Kaninchen.

The question of a possible brain damage during open heart surgery using extracorporeal circulation is still a problem, especially in infants with circulatory arrest under deep hypothermia. During the last years Magnetic Resonance Spectroscopy was developed, and with this method we have now a possibility to study brain energy metabolism non-invasively and continuously. Our aim was to develop an animal model (rabbit) for studying brain energy metabolism by 31-P Magnetic Resonance Spectroscopy during extracorporeal circulation. In a first step we have shown that the influence of hypothermia on energy metabolism in the brain can be measured in the intact animal by MR-Spectroscopy. In a second step a non-magnetic heart-lung machine for rabbits was constructed and is described here. We get a completely normal brain spectrum in the beginning and after two hours of extracorporeal circulation. The spectrum is also normal on extracorporeal circulation at 35 degrees C and during cooling down to 18 degrees C. With this animal model it will be possible to study different variables of extracorporeal circulation such as duration of circulatory arrest under deep hypothermia or changes of the priming including pharmacological changes.

[Kawasaki syndrome]. / Das Kawasaki-Syndrom.

Kawasaki syndrome was first described in 1967 in Japan. It is due to a generalized vasculitis of probably infectious etiology. Diagnosis is based exclusively on clinical criteria. Both morbidity and mortality are mainly determined by coronary artery involvement. The principal purpose of the present analysis of the 32 patients treated for Kawasaki syndrome at the University Children's Hospital in Berne (22 males = 69%, 11 females = 31%; mean age +/- SD = 2.7 +/- 2 years) was to describe the clinical and laboratory presentation and to evaluate high-risk factors and therapeutic efficacy with regard to course of the disease and cardiac involvement. Treatment has included aspirin and, since 1986, intravenous immunoglobulins (IVIG) as well. Routine electrocardiographic and echocardiographic checks detected 10 patients (31%) with cardiovascular complications, all of whom remained clinically asymptomatic: 9 with carditis (28%) and 3 with coronary artery aneurysms (CAA) (9%). The 3 patients with CAA were boys aged 18-25 months who presented an extremely long duration of fever (12-30 days) and markedly elevated ESR (100-128 mm/h). Since the therapeutic use of high-dose IVIG (9 patients), no CAA has been observed, and carditis in only 2 patients (22%). All patients are clinically cured. The carditis findings and 2 of the 3 CAA completely resolved; one patient has persistent CAA and myopathic cardiomegaly after more than 3 1/2 years. This study, together with the review of the literature, should enable the physician to diagnose and correctly manage the childhood disease Kawasaki syndrome.

[Acute therapy of cardiovascular malformations in infancy: non-surgical measures]. / Akuttherapie kardiovaskulärer Missbildungen im Säuglingsalter: nicht-chirurgische Massnahmen.

Non-surgical acute therapeutic procedures in infants replacing immediate surgery are mainly indicated in life threatening cyanosis and/or cardiac failure in the first 2 to 4 weeks of life. Balloon septostomy replacing surgical creation of an atrial septal defect, and pharmacological manipulation of the ductus with prostaglandin E in newborns (opening of ductus replacing aortopulmonary shunt) or by inhibition of prostaglandin synthesis with indomethacin in premature babies (ductus closure replacing ligation of ductus) are used routinely nowadays. Balloon dilatation of stenotic pulmonic or aortic valves (replacing valvotomy), balloon dilatation of coarctation of the aorta (replacing operative correction) and, rarely, closure of vessels with the help of catheters (replacing ligation) are being increasingly tried in this age group as well, though they do not yet belong to the routine methods.