Safety and effectiveness of very-high-power, short-duration ablation in patients with atrial fibrillation: Preliminary results

Background: Pulmonary vein isolation (PVI) is at the forefront of rhythm control strategies in patients with atrial fibrillation (AF). A very-high-power, short-duration (vHPSD) catheter, QDot Micro (TM) (Bio-- sense Webster) was designed to improve the effectiveness of AF ablation within a shorter procedure time. The aim of this study was to compare the effectiveness and safety of PVI ablation between this vHPSD ablation mode and conventional ablation-index-guided ablation (ThermoCool Smarttouch SF catheter). Methods: This single-center, retrospective, observational study enrolled 108 patients with AF, referred for catheter ablation between December 16, 2019 and December 3, 2021. In 54 procedures (mean age: 58.0 +/- 12.3; 66.67% male), a QDot Micro(TM )catheter was used (vHPSD-group), and 54 patients (mean age: 57.2 +/- 11.8; 70.37% male) were treated with a ThermoCool Smarttouch (TM) SF catheter (AI-group). The primary endpoint was freedom from AF 3 months after ablation. Results: Atrial fibrillation was found to recur in 14.81% of patients in the vHPSD-group and in 31.48% of patients in the AI-group (p = 0.07). There was no difference in treatment-emergent adverse events between the two groups (6.3% vs. 0%; p = 0.10). One severe adverse event (a cerebral vascular accident) was observed in the vHPSD-group. The mean dose of remifentanil was reported to be lower during QDot Micro (TM) catheter-based PVI (p < 0.001). The vHPSD-based PVI was associated with shorter radiofrequency application time (p < 0.001), fluoroscopy time (p < 0.001), and total procedure time (p < 0.001). Conclusions: This study suggests vHPSD ablation is safe, can reduce the dosage of analgesics during significantly shorter procedures and may enhance the success rate of catheter-based PVI.