The congenital long QT syndrome.
OBJECTIVE
The long QT syndrome (LQTS) is a disorder of the electrical system of the heart, due to dysfunction of the ion channels and involving the repolarisation process. The inherited form occurs when there is a mutation in one of the genes which encode the making of a channel. Prolongation of the QT interval renders the patient vulnerable to an arrythmia called torsade de pointes, resulting in syncope and sudden death.


METHODS
Three children with the congenital long QT syndrome presented to the pediatric department, one of them also having a 2:1 atrio-ventricular block. The parents and siblings of these children were screened for the long QT syndrome with an electrocardiogram. 2D echocardiography was done to rule out structural abnormalities and audiometry for deafness.


RESULTS
Four family members were identified on screening to have LQTS. Propranolol was started on all children with LQTS. The child with heart block also received a pacemaker. LQTS must be considered in all patients presenting with syncope especially if associated with deafness and/or a family history of sudden deaths in infancy or childhood.


CONCLUSIONS
The corrected QT interval must be determined in all children with heart block since the two conditions are often associated.
Shanbag
Preeti
P
Pediatric Intensive Care Unit (PICU), Department of Pediatrics, Lokmanya Tilak Municipal Medical College & General Hospital, Sion, Mumbai, India. pshanbag@yahoo.com
Govindakumar
Preetha T
PT
Vaidya
Mamta
M
Joshi
Varsha
V
Shahid
Sukhbir Kaur
SK
D002648:Child; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007223:Infant; D008133:Long QT Syndrome / Q000151:congenital* / Q000175:diagnosis* / Q000628:therapy; D008297:Male; D010138:Pacemaker, Artificial; D010375:Pedigree; D011379:Prognosis; D011433:Propranolol / Q000008:administration & dosage; D018570:Risk Assessment; D016896:Treatment Outcome
D011433:Propranolol