The aim of this single-center prospective randomized controlled trial is to assess the superiority of contact-force-(CF)-sensing-based approach compared to conventional (non-CF-sensing) approach in the catheter ablation of PSVTs, and to investigate the safety of open-irrigated, contact-force-sensing ablation catheters (used in a "non-irrigated" mode) in these procedures.

Rationale:

Multiple studies have demonstrated the importance of adequate catheter-tissue contact in the creation of effective lesions during radiofrequency catheter ablation. The development of contact-force(CF)-sensing catheters have contributed significantly to improve clinical outcomes in atrial fibrillation 3-18. However CF-sensing technology is not used in the ablation of paroxysmal supraventricular tachycardia. Although PSVT ablation with the conventional approach (non-irrigated, non-CF-sensing catheters) is considered a relatively low-risk procedure with fairly high success rate (short-and long-term) 1,2,19, we hypothesize that contact-force sensing can further improve the outcomes of these procedures. Based on the results of studies on atrial fibrillation ablation (mentioned above) we believe that CF-sensing could similarly improve such important parameters as radiofrequency (RF) application number/time, total procedure time, and fluoroscopy time in cases of PSVT ablations, as well. In addition CF-sensing could also further improve acute success/recurrence rates of PSVT ablation, and might also be capable to further diminish complication risk.

Primary Objective:

The primary objective of the present study is to demonstrate the superiority of contact-force-sensing in the ablation of AVNRT and WPW-AVRT as assessed by the improvement in the number and duration of radiofrequency applications compared with the conventional ablation approach.

Secondary Objective:

Secondary objectives of the study are the followings:

• to demonstrate that contact-force-sensing catheters are superior in terms of total procedure duration and fluoroscopy times in the case of AVNRT/WPW-AVRT ablation.
• to show that the use of contact-force sensing catheters is non-inferior to conventional catheters (without contact-force-sensing) in terms of acute/long-term procedural success and procedural safety (major/minor complication rate) of AVNRT/WPW-AVRT ablations.

Study population:

All patients above 18 years without structural heart disease being referred for electrophysiological study and potential treatment with radiofrequency catheter ablation of atrioventricular nodal reentrant tachycardia (AVNRT) and atrioventricular reentrant tachycardia (AVRT) with manifest (WPW syndrome) or concealed accessory pathways.

Intervention:

One group undergoes manual ablation using standard non-irrigated ablation catheters and the other group undergoes manual ablation with an open-irrigated ablation catheter equipped with CF- sensing (and utilized in a non-irrigated mode during ablation)

Main study parameters/endpoints:

The main study endpoint is the difference in RF application number during the procedures of AVNRT/WPW-AVRT ablation; secondary endpoints are differences in RF application rate, acute success rate, long-term recurrence rate (1 year) major/minor complication rate, and total procedure/fluoroscopy time.

Inclusion Criteria:

• Referral for electrophysiology study because of pre-excitation on 12-lead surface ECG and/or documented (or suspected) symptomatic PSVT
• Identification of AVNRT or WPW-AVRT (with manifest or concealed accessory pathway) during standard EP study
• Verbal consent to continue with ablation therapy
• Informed written consent to be included in the study

Exclusion Criteria:

• evidence of structural heart disease and/or myocardial ischemia
• pregnancy (and lack of exclusion of potential pregnancy)
• age below 18 years