DIAGNOSIS AND OUTPATIENT TREATMENT OF CHILDREN WITH LONG QT SYNDROME: LONG-TERM OUTCOMES

Aim To assess the diagnostic accuracy of long QT syndrome in children and to estimate the results of the follow-up.

Methods High-risk groups of children with bradycardia less than the second percentile and/or a family history of sudden death syndrome, and children with syncope diagnosed with the ECG testing were included in the study. All patients underwent routine medical examination, molecular genetic testing and were followed-up for 3,5–10 years.

Results The majority of children haves transient corrected QT prolongation secondary to therapy, requiring ECG monitoring. High-risk group screening reports higher rates of idiopathic LQTS. ECG testing shows its efficiency among asymptomatic children with a normal heart rate. Patients present with syncope at the outpatient settings require the exclusion of a wide range of diseases, both congenital and acquired heart disease. The clinical status of the examined patients does not always correspond to the known LQTS variants. Molecular genetic analysis provides relevant information on the genetic heterogeneity of the disease, including new mutations, both pathological and beneficial ones.

Conclusion Regardless of the presence or absence of molecular genetic confirmation of LQTS, beta blocker therapy in some cases combined with implanted cardioverterdefibrillator prevents the development of the adverse events in the long-term period and ensures normal emotional, intellectual and physical development.

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