[Efficacy of radiofrequency catheter ablation of outflow tract ventricular arrhythmias in children].

OBJECTIVE: To explore the features of outflow tract ventricular arrhythmias (OTVA) in children and evaluate the efficacy and experiences of radiofrequency catheter ablation (RFCA). METHOD: Data were collected and analyzed on 53 consecutive pediatric patients who underwent RFCA for OTVA from January 2012 to July 2015 in the First Hospital of Tsinghua University. These children included 34 male and 19 female, whose average age was (8±3) years and body weight was (33±13) kg. All the children met the indication criteria for RFCA of OTVA in children. Data were analyzed about the onset age, the forms and ablation efficacy and strategies of OTVA. RESULT: The average age of onset was (8±4) years. Of these children, 68% (36/53) had frequent premature ventricular complex which was the main arrhythmia pattern.The proportion of 66%(35/53) were of right ventricular outflow tract (RVOT). The vast majority of RVOT ventricular arrhythmias originates from myocardium with in the first 1 cm beneath the pulmonary valve(89%, 31/35) or the septal region(77%, 27/35). The total acute success rate was 98%(52/53), the recurrence rate on follow-up was 10% (5/52) and the complications of the procedure was 2%(1/53). The X-ray exposure dose was(743±323) mGay·cm(2). However, for 6 of the children RFCA on both sides of outflow tract was necessary for success. CONCLUSION: OTVA in children originates mostly from RVOT. RFCA can be used for ablation of pediatric OTVA effectively and safely. In some cases, successful RFCA should be performed on both sides of outflow tract.