[Anti-arrhythmia efficacy of propafenone in children. Apropos of 30 cases]. / Efficacité anti-arythmique de la propafénone chez l'enfant. A propos de 30 cas.

Thirty children aged from 3 months to 20 years were treated with propafenone 250 to 650 mg/m2 divided into 2 to 4 daily doses, for a mean period of 14 months (range: 4 days to 5 years); 8 had chronic atrial tachycardia, 9 had junctional arrhythmia and 13 had ventricular arrhythmia. There were 17 good results (suppression of the arrhythmia), 7 fair results (good clinical effect but partial persistence of the arrhythmia) and 6 failures, either because the drug proved ineffective (3 cases) or on account of side-effects (3 cases). In the treatment of chronic atrial tachycardia propafenone seemed to be more effective than amiodarone in 3 cases and as effective as that drug in 2 cases. In junctional arrhythmia propafenone was certainly effective but unpredictably so (3 good results, 2 fair results, 4 failures). Among ventricular arrhythmias, ventricular tachycardia in bursts was the one which benefited most regularly from treatment with propafenone: the results in 8 patients were better than those obtained with other antiarrhythmic agents (class I drugs, beta-blockers, calcium antagonists); only amiodarone proved superior to propafenone in this type of arrhythmia. Despite a 27% incidence of side-effects, propafenone was generally well tolerated by the children, with no significant gastrointestinal disorders. No depressive effect on the myocardium was noted in 6 children with moderate heart failure well controlled by digitalis and diuretics. However, since overdosage may cause severe disorders of conduction with widened ventriculogram, we recommend regular ECG monitoring during the first 3 days of treatment at least: although there is little slowing down of sinus rate (12%) and little modification of the slow phase under treatment, serious toxicity is possible. Thus, propafenone is a drug that should be handled with caution, but it constitutes a major addition to the range of antiarrhythmic agents which can be used in paediatrics.

[Arrhythmia after atrial correction of transposition of the great vessels. Holter recording study of 123 surgically treated patients]. / Troubles du rythme après corrections atriales des transpositions des gros vaisseaux. Etude par enregistrement Holter de 123 opérés.

Sinus node dysfunction after intra-atrial repair of transposition of the great arteries by a Mustard or Senning procedure is well known. We undertook this study to evaluate the frequency, the nature, the severity and evolution of these dysrhythmias by performing Holter monitoring in 123 children followed up over 5 years; 302 Holter recordings were reviewed. The patients were divided into 3 groups of increasing severity: I = no sinus node dysfunction, II = moderate sinus node dysfunction, III = severe sinus node dysfunction with bradycardia of less than 30/min and/or pauses of over 2000 ms. The association of atrial hyperexcitability was classified in 3 subgroups: A = no extrasystoles, B = at least 4 extrasystoles per 24 hours, C = atrial tachycardia (focal tachycardia or flutter) after the first six postoperative months. There were only 15% of normal recordings (IA) and the majority of children (58%) were classified in the intermediary groups (IB, IIA and IIB). Sinus node dysfunction tended to become more severe with time in nearly 30% of the 69 cases followed up sequentially. The bradycardia tended to become more severe and associated with episodes of atrial tachycardia: the frequency of type B and C increased to 30% in Group I, to 68% in Group II and to 91% in Group III. The attacks were severe, especially in patients with a mediocre postoperative haemodynamic result. This explains the global mortality of 3%, the morbidity of 15% and the pacemaker implantation rate of 12%.(ABSTRACT TRUNCATED AT 250 WORDS)

[Medical treatment and long-term development of permanent reciprocal tachycardia in children. Apropos of 10 cases followed for 11 years]. / Traitement médical et évolution à long terme des tachycardies réciproques permanentes de l'enfant. A propos de 10 cas suivis durant 11 ans.

Incessant reciprocating tachycardia (IRT) was diagnosed in 10 children aged 0-11 years (mean 2.5 years), followed-up for an average of 11 years (range 4-22 years). 8 children were treated for an average period of 2.8 years (range 0.5-6 years) with the association of amiodarone and digitoxine. All children were treated initially or secondarily with verapamil and/or betablockers with digitoxine for an average of 4.6 years (range 1-9 years). The true frequency of IRT, its tolerance and the age at diagnosis did not indicate the probable required length of treatment with amiodarone, but only the initial response to this drug. Finally, 5 patients were cured and in sinus rhythm, and the other 5 were well controlled, having only occasional bursts of tachycardia. When we compared one group of 5 cases with clinical signs of cardiac failure and radiological cardiomegaly (CTR greater than 0.60) with a second group of 5 cases in which the arrhythmia was better tolerated, surprisingly, the frequency of intreated IRT was not t he factor which influenced its tolerance (198/min vs 194/min). On the other hand, the following differences were observed between the two groups: a younger age at diagnosis in the first group (5 months vs 4.6 years) responsible for the longer follow-up period (14.5 vs 7 years), earlier treatment period with amiodarone (3.6 years compared to 5.5 years) and a longer treatment period with this drug (3.5 vs 2 years). It was only at about the age of 7 that this treatment could be withdrawn or changed with half the children completely cured, and the other half only controlled.(ABSTRACT TRUNCATED AT 250 WORDS)

[Paroxysmal Hisian tachycardia and familial sarcoidosis]. / Tachycardie hisienne en salve et sarcoïdose familiale.

We report a His-bundle tachycardia in a 6 year-old patient without evidence of heart disease. Diagnosis and follow-up were assessed by exercise stress testing and repeated long-term electrocardiographic recording. As sarcoidosis was present in the mother and the aunt, this condition was discussed in this child also. However, since there is no absolute proof for this disease, the hypothesis of an antenatal injury of the bundle of His was discussed: this could be secondary to the transplacental transfer of abnormal maternal antibodies, as frequently observed in women with clinical or biologic evidence of connective tissue disease.

Amiodarone in the treatment of cardiac arrhythmias in children: one hundred thirty-five cases.

Oral amiodarone was given to 135 children (mean age, 10.2 years) for a mean duration of 4.1 months (range, 1 day to 6 years) for mainly idiopathic (25%) and postoperative (61%) arrhythmias. Complete ECG control or partial ECG control with clinical improvement was obtained in 60% and 33% of cases, respectively, regardless of the arrhythmia location (atrial 69%, junctional 16%, and ventricular 15%), mechanism, resistance (55%) or sensitivity (45%) to other drugs, and presence of cardiomegaly (40%) or clinical signs of heart failure (27%). The only factor favoring improvement was a short history (< 2 months in 54%). The rapid onset of drug effect (4.1 days), the early relapses after treatment discontinuation (3.3 weeks), and the absence of side effects due to drug accumulation reflect a faster metabolism than that in adults, with no cardiac toxicity and a low incidence of thyroid dysfunction (2 hyperthyroid, 1 hypothyroid).

[Congenital bundle-of-his focal tachycardias. Cooperative study of 7 cases]. / Tachycardies focales hissiennes congénitales. Etude coopérative de sept cas

The authors described seven cases of supraventricular tachycardia with atrio-ventricular dissociation, associated with the activity of an automatic focus in the bundle of His. These tachycardias, which appear at birth or are discovered at a very young age, appear to be congenital and sometimes familial, and are always isolated, having no associated cardiac abnormality. They give rise to cardiac failure, which is more marked when the rate is high (180-260/mn) and particularly resistant to treatment. The most effective form of treatment is amiodarone, almost always used in combination with digitalis. The anatomical abnormality, which was studied in the first case, is a contricting fibrosis around the main trunk of the bundle of His, and the appearances are reminiscent of those found in conditions of congenital atrio-ventricular block.