Radiation exposure and fluoroscopy time in AVNRT ablation: role of 3D electroanatomical mapping.

BACKGROUND

Atrioventricular nodal reentrant tachycardia (AVNRT) is the most frequent regular supraventricular tachycardia in adults. Catheter ablation of the slow pathway is considered first-line therapy, offering high success with low complication risk. Conventional fluoroscopy-guided ablation, however, exposes both patients and operators to ionizing radiation. Three-dimensional (3D) electroanatomical mapping systems have emerged as a promising alternative to reduce radiation while maintaining efficacy.

METHODS

We retrospectively reviewed 170 patients who underwent AVNRT ablation between June 2023 and August 2025. A total of 112 patients were treated using conventional fluoroscopy guidance, and 58 patients underwent 3D mapping-guided ablation. Radiation exposure, fluoroscopy time, procedural outcomes, and complications were compared between groups.

RESULTS

Radiation dose, assessed by dose–area product (DAP), was significantly higher in the conventional group (3613.6 ± 1202 mGy·cm²) than in the 3D group (656 ± 189 mGy·cm², p < 0.05). Fluoroscopy time was likewise longer in the conventional group (638 ± 161 s vs. 291.6 ± 52.6 s, p < 0.05). Acute success was 98.2% in the conventional group and 100% in the 3D group. Two patients in the conventional group developed permanent atrioventricular block requiring pacemaker implantation, while one recurrence and one procedural failure were also recorded. In the 3D group, one patient experienced transient atrioventricular block requiring temporary pacing, with no recurrences.

CONCLUSION

Three-dimensional mapping significantly reduces radiation exposure without compromising safety or efficacy in AVNRT ablation. Adoption of this approach may enhance patient and operator safety in routine practice.