Radiofrequency Catheter Ablation for Paroxysmal Atrial Fibrillation and Supraventricular Tachycardia in Non-Fluoroscopic Versus Traditional DSA Catheterization Laboratories: Design and Rationale of the FREE-DSA Trial

Background Conventional radiofrequency catheter ablation (RFCA) has historically relied on fluoroscopic guidance, exposing patients and operators to ionizing radiation and contributing to cumulative occupational hazards. Although intracardiac echocardiography and three-dimensional electroanatomical mapping have enabled non-fluoroscopic ablation, prospective randomized evidence evaluating RFCA performed in a non-fluoroscopic catheterization laboratory remains limited. Objective This study aimed to evaluate whether RFCA performed in a non-fluoroscopic catheterization laboratory is noninferior to RFCA performed in a traditional DSA catheterization laboratory regarding procedural safety and acute procedural efficacy in patients with paroxysmal atrial fibrillation (AF) or supraventricular tachycardia (SVT). Methods The FREE-DSA trial is an investigator-initiated, multicenter, open-label, randomized, parallel-group, noninferiority trial conducted in China. A total of 1,260 patients with symptomatic paroxysmal AF or paroxysmal SVT will be enrolled from at least 10 centers and randomized in a 1:1 ratio to undergo RFCA in either a non-fluoroscopic catheterization laboratory or a traditional DSA catheterization laboratory. Randomization is stratified by participating center and arrhythmia type. Clinical endpoints will be adjudicated by an independent committee blinded to treatment allocation. Results The primary safety endpoint is the incidence of procedure-related complications occurring during the index procedure or within 3 months after ablation. The key secondary procedural efficacy endpoint is immediate procedural success. Additional secondary endpoints include procedural times, radiation exposure, hospitalization-related economic outcomes, and 3-month arrhythmia recurrence. Conclusion The FREE-DSA trial will provide randomized evidence regarding the safety and feasibility of RFCA in a non-fluoroscopic catheterization laboratory and may inform future radiation-sparing electrophysiology practice.