Cardiac electrophysiologic study in children. Preliminary report from Turkey.

Eighteen children (10 females, 8 males; age range 5.5 to 17 years, median: 10 years) who suffered from recurrent syncope, drug refractory supraventricular tachycardia and atrioventricular block or bradycardia were evaluated by cardiac electrophysiologic study between August 1988-April 1990. During the study, basal intervals were measured and the conduction system and sinus node functions were investigated. In some patients the mechanism of the tachycardia was investigated and drug-electrophysiologic studies also performed. Two of 6 cases with recurrent syncope had positive electrophysiologic findings and adequate treatment resolved the symptoms. The others have been followed. The mechanism of the tachycardia was determined in 5 cases with drug refractory supraventricular tachycardia and drug-electrophysiologic studies were done in all of them. The site of block was determined in 7 patients with atrioventricular block and pacemaker implantation was done in 5 patients. The results emphasized the usefulness of cardiac electrophysiologic study in childhood arrhythmias.