Comparison of COOL-Tip catheters vs Usual 4 mm catheters for radiofrequency ablation of accessory pathways and idiopathic ventricular arrhythmias

INTERVENTION: 1:1 randomization to COOL‐Tip catheters and usual 4 mm catheters for ablation. Efficacy of RFCA within 300 or 600 sec of radiofrequency energy delivery for treatment of ACP, ACP‐T and idioapathic PVC/CT CONDITION: Accessory pathways and idiopathic ventricular arrhythmias ; Circulatory System ; Ventricular fibrillation and flutter PRIMARY OUTCOME: 1. Procedural success rate; 300 sec of radiofrequency energy application; procedural success rate wtihin 300 sec of radiofrequency energy application (total ablation time <300 sec); 2. Need for cross‐over; 300 sec radiofrequency energy applications with suboptimal power or impedance or after 600 sec of failed radiofrequency energy application with optimal parameters of mapping and RF energy supply; need for additional use of COOL‐Tip catheter (in usual 4 mm tip group) or additional COOL‐Tip catheter in COOL‐Tip group SECONDARY OUTCOME: 1. Procedural success rate; 600 sec of radiofrequency energy application; procedural success rate within 600 sec of radiofrequency energy application (total ablation time<600 sec).; 2. Cumulative duration of ablation energy delivery (sec); periprocedural; 3. RF ablation time (sec); periprocedural; 4. Duration of fluoroscopic exposure (min); periprocedural; 5. Procedural duration (min); periprocedural; 6. Early procedural complication rate within 24 hours after procedure; 7. Late camplication rate 24 hours to 12 months after procedure INCLUSION CRITERIA: 1. Accessory pathway or idiopathic PVC/VT qualified for ablation 2. Electrophysiologically confirmed arrhythmia mechanism and procedure endpoint 3. Age above 18 years, either sex 4. Signed patient informed consent for participation in the study