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Background— β-Blocker efficacy in long-QT syndrome type 1 is good but variably reported, and the causes of cardiac events despite β-blocker therapy have not been ascertained. Methods and Results— This was a retrospective study of the details surrounding cardiac events in 216 genotyped long-QT syndrome type 1 patients treated with β-blocker and followed up for a median time of 10 years. Before β-blocker, cardiac events occurred in 157 patients (73%) at a median age of 9 years, with cardiac arrest (CA) in 26 (12%). QT-prolonging drugs were used by 17 patients; 9 of 17 (53%) had CA compared with 17 of 199 nonusers (8.5%; odds ratio, 12.0; 95% confidence interval, 4.1 to 35.3; P P P =0.001). None of the 26 patients with CA before β-blocker had CA/sudden death on β-blockers. Conclusions— β-Blockers are extremely effective in long-QT syndrome type 1 and should be administered at diagnosis and ideally before the preteen years. β-Blocker noncompliance and use of QT-prolonging drug are responsible for almost all life-threatening “β-blocker failures.” β-Blockers are appropriate therapy for asymptomatic patients and those who have never had a CA or β-blocker therapy. Routine implantation of cardiac defibrillators in such patients does not appear justified.

Objectives: To investigate the clinical profile, natural history, and optimal management of persistent or permanent junctional reciprocating tachycardia (PJRT) in children. Methods and results: 85 patients meeting the ECG criteria for PJRT were enrolled in a retrospective multicentre study. Age at diagnosis varied from birth to 20 years (median 3 months). Follow up ranged from 0.1 to 26.0 (median 8.2) years. At the time of referral, 24 of 85 patients (28%) had congestive heart failure that was resolved with medical treatment in all patients. Eighty three patients received drug treatment initially. Amiodarone and verapamil were the most effective with a success rate of 84–94% alone or in association with digoxin. Radiofrequency ablation of the accessory pathway was performed in 18 patients. There was a trend for a relation between age at ablation and the result of the procedure, failures being more common in younger patients (three of six procedures in younger and 15 of 18 in older children were successful; p = 0.14). Two patients with persistent left ventricular dysfunction on echocardiography but with no symptoms of congestive heart failure died suddenly one month and three years after diagnosis. PJRT resolved spontaneously in 19 patients (22%). Age at diagnosis of PJRT was not a predictor of spontaneous resolution. Conclusions: PJRT is a potentially lethal arrhythmia in children with tachycardia induced cardiomyopathy. Spontaneous resolution of tachycardia is not uncommon. Antiarrhythmic treatment is often effective. Radiofrequency ablation should be performed in older children or when rate is not controlled, especially in patients with persistent left ventricular dysfunction.

Objective: To study the fetal response to prenatal therapy in non-hydropic fetuses with supraventricular tachycardia (SVT) as a function of fetal haemodynamic status at presentation. Study Design: Retrospective study. Material and Methods: Between 1990 and 2000, 40 non-hydropic fetuses presented with SVT. Twenty-eight had reciprocating SVT and 12 had atrial flutter. Ten fetuses had significant tricuspid valve regurgitation. All fetuses were treated prenatally. The main outcome measurement was fetal response to therapy as assessed by the rate of prenatal SVT reduction and by the mean time interval to sinus rhythm restoration. Results: The mean gestational age at presentation was 29 ± 4.9 weeks. Overall, there were 39 liveborns and 1 intrauterine death. Reduction of SVT was achieved prenatally in 32 cases (80%). Among the 30 cases without tricuspid regurgitation, prenatal conversion to sinus rhythm was achieved in 27 cases (90%) with a mean time interval of 7 days. Among the 10 fetuses presenting with tricuspid regurgitation, the rate of prenatal conversion was significantly lower (5/10) and the mean time interval to conversion was significantly longer (24 days; p = 0.04, Mann-Whitney test). In the subgroup treated by digoxin as first-line therapy (n = 32), the interval to sinus rhythm restoration was also significantly higher in the presence of tricuspid regurgitation, with a slightly but not significantly lower reduction rate. Conclusion: The response to prenatal therapy may be poorer in cases presenting with tricuspid regurgitation.

Smith-Magenis syndrome (SMS) is a clinically recognisable contiguous gene syndrome ascribed to interstitial deletions of chromosome 17p11.2. Patients have a phase shift of their circadian rhythm of melatonin with a paradoxical diurnal secretion of the hormone. Serum melatonin levels and day-night behaviour were studied in nine SMS children (aged 4 to 17 years) given acebutolol, a selective β1-adrenergic antagonist (10 mg/kg early in the morning). Cardiac examination, serum melatonin, motor activity recordings, and sleep diaries were monitored before and after drug administration. The present study shows that a single morning dose of acebutolol suppressed the inappropriate secretion of melatonin in SMS. A significant improvement of inappropriate behaviour with increased concentration, delayed sleep onset, increased hours of sleep, and delayed waking were also noted. These results suggest that β1-adrenergic antagonists help to manage hyperactivity, enhance cognitive performance, and reduce sleep disorders in SMS. Keywords: Smith-Magenis syndrome; circadian rhythms; melatonin

Isolated complete atrio-ventricular (AV) block in children occurs in anatomically normal hearts in the absence of any known predisposing factor likely to have caused the block. This study aimed to define the current prognosis of these conduction disorders.135 patients with isolated complete AV block, diagnosed before the age of 15 years, were included in this monocentric, retrospective study.52.6% of the cases were diagnosed in the antenatal or neonatal period, demonstrating their congenital nature. The disease was heralded by symptoms in only 6.7% of cases. A search for maternal anti-Ro/La antibodies was performed in 111 of the patients. It was positive in 56 cases, and was associated with an early diagnosis, a short delay in cardiac pacemaker implantation, and the occurrence of cardiomyopathy (16 cases), the latter representing a critical point in the progression of the disease (37.5% mortality at 6 years). Among the 55 cases not associated with antibodies, 2 cases were familial and no etiology was discovered in the others. The diagnosis was therefore made later, and no progression to cardiomyopathy was noted. A cardiac pacemaker was implanted in 122 patients (66 epicardial, 56 endocardial).Isolated complete AV block in children is not a homogenous entity: 'immunological' blocks are genuinely congenital and their prognosis remains grave, owing to the risk of cardiomyopathy, which is sometimes diagnosed late. The other types of block are diagnosed much later in childhood, and their mechanism is still unknown. They have a good prognosis as long as the indications for pacing the child are respected.

Hypertrophic cardiomyopathy (HCM) carries an increased risk of sudden death, especially in children and young adults. We investigated heart rate variability (HRV) in children with HCM, in order to evaluate its prognostic value. Seventeen patients (9 males and 8 females) with non-obstructive HCM were prospectively enrolled in the study. The diagnosis of HCM had been made between the ages of 1 month and 13 years (mean (SD) 71 (54) months). At the time of the study their ages ranged from 16 months to 16.5 years (mean 123 (70) months). HCM was defined by the presence of a hypertrophied, non-dilated left ventricle, in the absence of underlying cardiac, systemic disease or syndromic conditions. Four patients had a family history of HCM and two had a family history of premature (less than 50 years) sudden cardiac death of a first degree relative. At the time of the study, no patients were receiving treatment. Seven patients complained of moderate exertional dyspnoea; no patient had a history of chest pain or syncope. Standard 12 lead ECG showed that seven patients had abnormal repolarisation. On 24 hour monitoring, all patients were in stable sinus rhythm, and no arrhythmia was recorded. Ten patients underwent exercise testing and none had hypotension, arrhythmias or ischaemia during exercise. Five patients …

Prior to putting in place a percutaneous device, the assessment of the atrial septal defect anatomy is mandatory. The 3D transthoracic echocardiography is a non-invasive method bringing an imaging of the septal defect surface and its borders. Fifty-two patients ageing from 3 to 16 years old had a rotational 3D transthoracic echocardiography. Thirty-six (69%) were selected for a percutaneous closure (borders7 mm and a septal surface/atrial septal defect ratio2). Thirty-two of these selected patients (89%) benefited from the Amplatz prosthesis implantation with success. The maximal 3D diameter of the septal defect was 20 + 4 mm (14-30) compared to the mean size of prosthesis at 22 mm (18-30). Four of the 36 patients (aneurismal septum or a borderline septal surface/atrial septal defect ratio) were secondarily oriented to surgeons. Sixteen patients (31%) were selected directly to a surgical closure. The lack of borders or septal surface were confirmed by the surgical view. The 3D transthoracic echocardiography allows to define new criteria for the selection of patients prior to a percutaneous closure of atrial septal defects. This prospective study demonstrates that 9 out of 10 patients who had the 3D criteria had a percutaneous closure of the septal defect.

OBJECTIVETo evaluate the quality of life in patients with univentricular heart and to determine the impact of sociodemographic and clinical characteristics.DESIGN AND SETTINGRetrospective, cross sectional study conducted in a regional paediatric cardiology centre.PATIENTSThe health records of 89 survivors with univentricular heart (median age 21 years; range 17–49 years) were reviewed. Sixty seven answered the Duke questionnaire. Sociodemographic and clinical variables were similar in the responders and non-responders. The impact of sociodemographic and clinical variables on individual Duke's measures was assessed.RESULTSThe Duke scores of adults with univentricular heart were similar to the normal population. Cyanosis predicted a worse score for physical (p = 0.05) and perceived health measures (p = 0.02). A higher educational level predicted a better score for physical (p = 0.004), mental (p = 0.01), and general health measures (p = 0.02). Orthopaedic problems worsened the social score (p = 0.05). Psychosocial problems worsened the pain score (p = 0.04). In comparison with the other anatomical types, mitral atresia worsened the perceived health score (p = 0.02). Patients younger than 23 years scored better for almost all health and dysfunction measures.CONCLUSIONSDespite repeated interventions and other disease related everyday stresses, a selected group of adults with univentricular heart had a satisfying quality of life.

From January 1975 to January 1987, 21 consecutive infants aged less than six months (mean (SD) 2.6 (1.2] were admitted with anomalous origin of the left coronary artery from the pulmonary artery. In the first 12 patients, who were seen up to 1982, operation was performed after the age of one year (mean (SD) 29 (29) months) (group 1). The next nine infants, seen from 1983 to 1987, had their operations within a few weeks of the onset of symptoms (mean (SD) age 4.8 (1.4) months) (group 2). In group 2 the left coronary artery was relocated into the aorta, whereas in group 1 there was additional resection of the left ventricular wall or mitral valvoplasty or both. At presentation there were no differences in age, clinical condition, heart enlargement, and echocardiographic left ventricular dysfunction between groups 1 and 2. Seven of the 12 patients in group 1 died, five while they were awaiting operation (three died suddenly at home) and two at operation. The five survivors are doing well 6.4 (3.1) years after operation with normal left ventricular function which improved slowly over several months after operation. Two of the nine patients in group 2 died; both deaths occurred at or soon after operation. The seven survivors are doing well 1.8 (0.9) years after operation. In three, left ventricular function recovered within three weeks; and there was even partial or total regression of the Q waves in the supposedly necrotic areas. In the remaining four the pattern of improvement in left ventricular function resembled that in group 1. Operation should be undertaken early in infants with anomalous left coronary artery arising from the pulmonary artery because the procedure is relatively safe, prevents a high natural mortality, and offers a better chance of a faster recovery of left ventricular function.

From April 1984 to January 1986, anatomic surgical correction was performed in 50 newborn (2- to 23-day-old, mean 8 +/- 5 [SD]) infants with simple transposition of the great arteries. Before surgery, balloon atrial septostomy was performed in all patients, prostaglandin E1 was infused in 42, and left ventricular shape on a two-dimensional echocardiogram was considered "satisfactory" in 48. Surgery was performed in patients on cardiopulmonary bypass without cardiac arrest; the pulmonary artery was reconstructed by end-to-end anastomosis according to Lecompte's maneuver with a pericardial patch. In all but one patient coronary artery transfer was possible regardless of the distribution of these vessels. There were eight early deaths (16%), but only four (10%) of the last 41 patients treated died. There was one late death (2%) due to a secondary myocardial infarction caused by compression of the left coronary artery. Reoperation was successfully performed in two patients for supravalvar pulmonary artery stenosis. The only late medical complication was a transient episode of myocardial ischemia 6 months after surgery. The 41 late survivors were in excellent condition, were in sinus rhythm, and had a normal left ventricle 1 to 22 months after surgery (mean 7.2 +/- 5.4 [SD]). Aortic growth was normal; pulmonary artery supravalvar stenosis occurred in six patients (mild in four). We conclude that anatomic correction can be applied successfully in the first few days of life in newborns with simple transposition of the great arteries, regardless of coronary distribution.

From April 1984 to April 1987, surgical anatomic correction was performed in 86 newborn infants, 2-23 days old (6.8 +/- 3.6 days, mean +/- SD) with simple transposition of the great arteries. In all patients, the pulmonary artery was reconstructed by end-to-end anastomosis according to the Lecompte maneuver, including eight patients with side-by-side position of the great arteries. Three different approaches were used. In the first 10 patients (group 1, six survivors), two separate patches of preserved tanned pericardium were used to reconstruct the pulmonary artery, whereas in the next 15 patients (group 2, 13 survivors), a single patch of the same material was used, and in the last 61 patients (group 3, 56 survivors), surgery was performed with a single patch of fresh autologous pericardium. Among the 75 survivors, 68 (including six in group 1, 12 in group 2, and 50 in group 3) were followed serially for at least 6 months (6-48 months, 26 +/- 9 months) with sequential noninvasive evaluations. At follow-up, all were asymptomatic with normal growth. Two patients with severe pulmonary artery stenosis (group 1) were successfully reoperated on. Four infants with moderate pulmonary artery stenosis have been followed medically and have had stable right ventricular pressures. The last 62 patients have normal or near-normal right ventricular pressures. The spatial relation of the great arteries did not affect the quality of the results. Group 1 had clearly the worst results.(ABSTRACT TRUNCATED AT 250 WORDS)

To study heart rate variability (HRV) in patients operated for tetralogy of Fallot (ToF) and to identify any correlation between HRV and ventricular tachycardia (VT).We studied HRV in 23 consecutive patients operated for ToF (mean age 14 +/- 6.6 years; mean follow-up 10.6 +/- 5.2 years). Seven patients had non-sustained VT on Holter monitoring. Two control groups were included: 18 healthy subjects and 15 patients operated for other congenital heart disease. There were no differences in age, age at surgery (in the operated groups), follow-up, and mean heart rate between the three groups. Four time and four frequency domain indices were calculated: mean duration of RR intervals, standard deviation of all RR intervals (SD), square root of the mean squared differences of successive RR intervals (r-MSSD), percent of differences between adjacent RR intervals (pNN50), total power (TP), low frequency (LF), high frequency (HF), and LF/HF ratio.HRV indices were identical in the two control groups but were significantly reduced in patients with ToF. Within the patients who had been operated on for ToF, HRV indices were significantly lower in the seven with non-sustained VT than in those without arrhythmias: SD (95 +/- 15 vs. 135 +/- 54 ms; p = 0.01), r-MSSD (26 +/- 9 vs. 45 +/- 20 ms; p = 0.03), pNN50 (4.4 +/- 3.4 vs. 16.5 +/- 12.5%; p = 0.001) and HF (111 +/- 97 vs. 352 +/- 291 ms(2); p = 0.009). Using stepwise multivariate regression analysis, pNN50, age at surgery, degree of pulmonary regurgitation and higher right/left ventricular ratio were independent predictive variables for VT (p0.0001; r(2) = 0.85).ToF patients, particularly those with ventricular arrhythmias, have significant impairment of sympatho-vagal balance, characterized by a reduction of vagal drive.