Background: Pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF) has been shown to be equally achievable and effective using High Power Short Duration (HPSD) radiofrequency ablation and cryoballoon ablation. Unlike cryoballoon, radiofrequency allows for the creation of additional ablation lines. AF in patients with structural heart disease presents a complex clinical challenge; however, data comparing the two ablation techniques in this population are scarce.

Methods: The study included 133 consecutive patients with AF (paroxysmal and persistent) and structural heart disease (coronary artery disease, dilated cardiomyopathy, moderate to severe mitral regurgitation). High Power Short Duration ablation (n=96) utilized a fixed protocol for energy delivery of 50 watts (contact force 3-20g). Cryoballoon (Medtronic, arctic front) was used in 37 patients. The endpoint of ablation was complete PV entrance and exit block, controlled by at least a 10-pole spiral catheter or a high-density catheter.

Results: Patients in the HPSD group were comparable in age, BMI, and CHA2DS2-VASc score. PVI was successfully achieved in all patients. Compared to cryoballoon, procedure time was significantly longer for HPSD (115.9±30.6 min vs. 90.05±23.26 min, p<0.01), as additional ablation lines were created in 13.54% of HPSD patients. Fluoroscopy time was comparable in both groups (HPSD 16.75±9 min and Cryoballoon 19.78±7.8 min; p=0.07). No major complications were observed in either group. There was one conservatively treated aneurysm spurium in the cryoballoon group and two in the HPSD group. Acute post-interventional pericarditis was higher in the HPSD group. At the one-year follow-up, symptomatic recurrences were 24.32% in the cryoballoon group and 17.53% in the HPSD group (p=0.46).

Conclusions: Pulmonary vein isolation using HPSD is equally effective and safe compared to cryoballoon PVI in patients with AF and structural heart disease. There was a non-significant trend toward a lower recurrence rate at the one-year follow-up with HPSD ablation, possibly due to additional substrate-based ablation lines, at the expense of longer procedure durations.