Electrophysiologic Study of Cardiac Conduction System in Children

Shin, Chae Ok; Hyun, Myung Chul

Abstract

PURPOSE: Pediatric cardiac arrhythmias are increasing but there is no normal values of cardiac electrophysiologic studies(EPS) in Korean children. So we performed cardiac EPS in children undergoing cardiac catheterization for mild congenital heart disease without cyanosis and ECG abnormality.
METHODS
We studied 24 children(male : 9, female : 15) with mild congenital heart disease(PDA : 10, VSD : 8, ASD : 6, age range 1.8 years to 9.3 years, mean 4.3 years). All studies were performed under propofol intravenous anesthesia. Fifteen minutes after cardiac angiography, two elctrophysiologic catheters were inserted through the right femoral vein into the right atrial appendage and His hundle area. Using atrial pacing with various cycle lengths for 30 seconds, we evaluated the sinus node recovery time(SNRT) and corrected sinus node recovery time(CSNRT) and atrioventricular block cycle length(AVBCL). Using atrial extrastimuli during sinus rhythm and paced 8 atrial rhythm, we evaluated the atrioventricular node effective refractory period(AVNERP) and total sinoatrial conduction time(TSACT).
RESULTS
Baseline sinus cycle length was 661 +/- 107 msec. SNRT and CSNRT were 955 +/- 181 msec, 264 +/- 68 msec each. AVBCL and AVNERP were 365 +/- 56 msec, 264 +/- 63 msec each. TSACT was 220 +/- 55 msec.
CONCLUSION
Considering the importance of pediatric cardiac arrhythmias, we have to have the normal EPS values in Korean children. But it is impossible to perform a invasive EPS for normal children without heart disease. So we believe that these measured values in children with mild congenital heart disease may be used as the normal value in Korean children.