Indications for radiofrequency ablation in children I. Paroxysmal supraventricular tachycardia 1. General age age > 3 years and weight > 15 kg. 2. ECG at the time of the attack is available. 3.Types: pre-excitation syndrome, atrioventricular node folding tachycardia, atrial tachycardia and atrial flutter. Idiopathic ventricular tachycardia 1. Generally age > 3 years, weight > 15 kg 2. With an electrocardiogram at the time of attack showing right ventricular outflow tract origin or left ventricular septal origin. 3. Echocardiography shows no organic heart disease. Ventricular premature beats 1. General age > 6 years, weight > 20 kg. 2. Frequent episodes of ventricular premature beats, persistence > 6 months, 24-hour premature beats > 10,000, or the number of premature beats > 10% of the total 24-hour heart rate.