Objective To evaluate retained fetal cardiovascular function after radio frequency ablation in complicated monochorionic diamnionic twins.Methods A total of 19 complicated monochorionic diamnionic twins [10 twin-twin transfusion syndrome (TTTS) and 9 selective intrauterine growth restricted (sIUGR)] who were diagnosed at Fetal Medicine Center of the First Affiliated Hospital of Sun Yat-Sen University from December 2013 to July 2015 were enrolled,and the cardiovascular profile score (CVPS) and Tei index of retained fetus were measured preoperatively and postoperatively at 24 h,3 days,1 week,1 month,2 months respectively.Each case was matched by normal fetuses with same gestational age as control group and the same parameters were measured.Results (1) TTTS:CVPS [(8.71 ± 1.11) scores] was increased significantly at 3 days postoperatively compared with preoperation [(6.86 ± 2.12) scores],and there was a statistical significance (t =2.571,P ＜ 0.05);CVPS [(9.29-± 0.95) scores] had no statistical significance 1 month postoperatively (P ＞ 0.05) as compared with controls [(10.00 ± 0.00) scores].Tei indexes of the left ventricle (LV-Tei) (0.41-± 0.06) and Tei indexes of the right ventricle (RV-Tei) (0.42 ± 0.06) decreased as compared with those before operation (LV-Tei:0.66 ± 0.19,RV-Tei:0.63 ± 0.12) with significant difference (LV:t =-3.193,P ＜ 0.05;RV:t =-3.565,P ＜ 0.05),but there was no statistical significance 1 month after operation(all P ＞ 0.05) as compared with the controls (LV-Tei:0.35-± 0.03,RV-Tei:0.35-± 0.03).(2) sIUGR:CVPS [(9.71 ± 0.45) scores] showed no statistical significance 1 week after operation (P ＞ 0.05) as compared with controls [(10.00 ± 0.00) scores].Tei indexes of the right and left ventricle 1 week after operation were lower than after operation with significant difference (LV-Tei:0.39 ± 0.04 vs.0.47 ± 0.06,t =-6.687,P ＜ 0.01;RV-Tei:0.38 ± 0.04 vs.0.47 ± 0.05,t =-6.000,P ＜ 0.01).Compared with the controls,RV-Tei (0.38 ± 0.04)had no statistical significance 1 week after operation (P ＞ 0.05),LV-Tei (0.36-± 0.02) showed no statistical significance 1 month after operation (P ＞ 0.05).Conclusions Retained fetal cardiovascular function of TTTS and sIUGR can be restored obviously after operation.In TTTS,its cardiovascular function is recovered completely 1 month postoperatively.In sIUGR,its cardiovascular function is recovered completely 1 week postoperatively.

Congenital heart disease is a type of common birth defect and most can be cured by surgery with prominent prolongation of life expectancy.But,different kinds of arrhythmias accompanied by congenital heart disease,especially late onset postoperative arrhythmias have become one of the major causes of mortality in these patients.Management and effective treatment for fast and slow arrhythmias associated with congenital heart disease are quite critical.

The occurrence rate of long QT syndrome is 1/2 000,which accounts for approximately 10％ of cases of the sudden infant death syndrome.The morbidity is decreased after receiving appropriate therapy in early stage.Electrocardiogram (ECG) screening,with reliable results,is simple and feasible in infancy and can be used to conduct appropriate genetic testing.Neonatal screening is controversial because of individual differences in ECG results.Even there are some defects,it is still necessary to perform neonatal ECG screening which can improve prognosis in children with long QT syndrome.

With a high success and low recurrence,catheter ablation has become the standard of cure in children with tachycardia.With the innovation of mapping ablation techniques,catheter ablation for children with tachycardia has been developed.In this review, green cardiac electrophysiology,complex arrhythmias ablation with electroanatomic mapping systems and cryoablation in children will be discussed.