Long QT syndrome with a de novo CALM2 mutation in a 4-year-old boy.
calmodulin mutation
catecholaminergic polymorphic ventricular tachycardia
long QT syndrome
pediatric
ventricular fibrillation
Journal
Pediatrics international : official journal of the Japan Pediatric Society
ISSN: 1442-200X
Titre abrégé: Pediatr Int
Pays: Australia
ID NLM: 100886002
Informations de publication
Date de publication:
Sep 2019
Sep 2019
Historique:
received:
01
05
2018
revised:
01
04
2019
accepted:
11
06
2019
pubmed:
10
7
2019
medline:
19
2
2020
entrez:
9
7
2019
Statut:
ppublish
Résumé
Human calmodulin (CALM) gene mutation has been reported to be related to inherited arrhythmia syndromes, but the genotype-phenotype relationship remains unclear. We report here a 4-year-old boy who had cardiac arrest while playing in a kindergarten playground. Cardiopulmonary resuscitation was initiated immediately. Eleven minutes after the cardiac arrest, ambulance crews arrived and an automated external defibrillator was attached. His heart rhythm, which was ventricular fibrillation (VF), was returned to sinus rhythm after only one shock delivery. The boy was brought to hospital by air ambulance. During transfer, electrocardiogram (ECG) showed transient VF. On arrival, chest radiograph showed a cardiothoracic ratio of 55% without pulmonary congestion. A 12-lead ECG showed a normal sinus rhythm, biphasic T wave, and prolongation of the corrected QT interval. On ECG, VF was preceded by torsade de pointes or frequent polymorphic premature ventricular contractions (PVC). Echocardiography showed a normal heart structure with decreased cardiac function. On the second day of hospitalization, ECG showed remarkable QT prolongation, T-wave alternans, and frequent PVC. Thereafter, propranolol was started. The ECG showed rapid improvement of QT prolongation and T-wave abnormality. Genetic test indicated a CALM2 mutation, and he was diagnosed with long QT syndrome-15 (LQT15). CALM mutations cause long QT syndrome (LQTS), catecholaminergic polymorphic ventricular tachycardia (CPVT) and idiopathic VF. This patient with a CALM2 p.N98S mutation had both phenotypes of LQTS and CPVT.
Sections du résumé
BACKGROUND
BACKGROUND
Human calmodulin (CALM) gene mutation has been reported to be related to inherited arrhythmia syndromes, but the genotype-phenotype relationship remains unclear.
METHODS AND RESULTS
RESULTS
We report here a 4-year-old boy who had cardiac arrest while playing in a kindergarten playground. Cardiopulmonary resuscitation was initiated immediately. Eleven minutes after the cardiac arrest, ambulance crews arrived and an automated external defibrillator was attached. His heart rhythm, which was ventricular fibrillation (VF), was returned to sinus rhythm after only one shock delivery. The boy was brought to hospital by air ambulance. During transfer, electrocardiogram (ECG) showed transient VF. On arrival, chest radiograph showed a cardiothoracic ratio of 55% without pulmonary congestion. A 12-lead ECG showed a normal sinus rhythm, biphasic T wave, and prolongation of the corrected QT interval. On ECG, VF was preceded by torsade de pointes or frequent polymorphic premature ventricular contractions (PVC). Echocardiography showed a normal heart structure with decreased cardiac function. On the second day of hospitalization, ECG showed remarkable QT prolongation, T-wave alternans, and frequent PVC. Thereafter, propranolol was started. The ECG showed rapid improvement of QT prolongation and T-wave abnormality. Genetic test indicated a CALM2 mutation, and he was diagnosed with long QT syndrome-15 (LQT15).
CONCLUSIONS
CONCLUSIONS
CALM mutations cause long QT syndrome (LQTS), catecholaminergic polymorphic ventricular tachycardia (CPVT) and idiopathic VF. This patient with a CALM2 p.N98S mutation had both phenotypes of LQTS and CPVT.
Substances chimiques
CALM2 protein, human
0
Calmodulin
0
Genetic Markers
0
Types de publication
Case Reports
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
852-858Informations de copyright
© 2019 Japan Pediatric Society.
Références
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