Changes in ventricular late potentials in children and adolescents with postural tachycardia syndrome / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the changes in ventricular late potentials (VLP) in children and adolescents with postural tachycardia syndrome (POTS).Methods One hundred and forty-four children and adolescents diagnosed as POTS by using the head-up tilt test (HUTT) in Second Xiangya Hospital of Central South University from January 2012 to March 2019 were selected as POTS group,their age ranged 4 to 16 years old [(11.03 ± 2.34) years old],there were 65 boys and 79 girls.Ninety-one healthy children and adolescents matched by age and gender [aged 4-16 (11.22 ± 1.68) years old,there were 50 boys and 41 girls] were selected as the healthy control group.VLP was measured by SR-1000A ECG automatic analyzer (Boai,Guangdong,China).Results Compared with the healthy control group,the prevalence of positive VLP in the POTS group increased [11.1％ (16/144 cases)vs.1.1％ (1/91 cases)],and the difference was statistically significant(x2=6.904,P ＜ 0.01);the heart rate in the POTS group increased compared with that in the healthy control group [82.0 (74.0-95.0) times/min vs.78.0 (71.0-86.0) times/min],and the difference was statistically significant (Z =-2.265,P ＜ 0.05);the low-amplitude signal (LAS40) in the POTS group prolonged compared with that in the healthy control group[23.0 (17.0-31.0) μV vs.19.0 (13.0-25.0) μV],and the difference was statistically significant (Z =-4.114,P ＜ 0.01);root mean square amplitude(RMS40) increased compared with that in the healthy control group [61.3 (34.4-79.1) ms vs.52.0 (38.8-64.5) ms],and the difference was statistically significant (Z =-2.469,P ＜ 0.05).There was no statistically significant difference in total QRS time (TQRS) between 2 groups [86.0 (76.0-97.5) ms vs.87.0 (81.0-94.0) ms,Z =-0.007,P ＞ 0.05].Conclusions The positive rate of VLP is increased of children and adolescents with POTS.It suggests that there is an abnormal cardiac electrical activity in children and adolescents with POTS.