Pulmonary Vein Isolation for Paroxysmal Atrial Fibrillation Using High-Power Short Duration Radiofrequency or Second-Generation Cryoballoon Ablation

Abstract Funding Acknowledgements Type of funding sources: None. Background Differences in the left atrial (LA) tissue loss can occur following different pulmonary vein isolation (PVI) techniques. Purpose Our prospective study compared the biomarker, the LA mechanical, and the electrophysiological findings as indicators of LA myocardial damage after a high-power short duration (HPSD) with contact force radiofrequency catheter and second-generation cryoballoon (CB2) ablation of paroxysmal atrial fibrillation (AF). Methods :We enrolled 40 patients with paroxysmal AF [16 (40%) women, mean age = 55.9 ± 12.4 years] who underwent HPSD (n = 21) or CB2 (n = 19). Biomarker levels (hs-cTnT, CK-MB, hs-CRP, LDH) and the transport function of the LA by transthoracic echocardiography (TTE) were compared pre and post procedurally. High-density mapping (HDM) was performed in sinus rhythm using a multielectrode diagnostic catheter in each group to define isolated left atrial low voltage area (LVA; <0.2mV in bipolar voltage mapping). LA CT-angiography and HDM merge was used to calculate the post-PVI LVA and the LVA/LA surface ratio. Results Postablation hs-cTnT and hs-CRP levels were comparable in the ablation groups (HPSD: 1249 ± 469 and 9.53 ± 10.30 vs. CB2: 995 ± 280 and 12.36 ± 5.76, p = 0.065 and p = 0.732), while CK-MB and LDH levels were significantly higher following CB2 ablation (HPSD: 6.61 ± 2.62 and 349.9 ± 65.6 vs. CB2: 26.01 ± 6.88 and 451.6 ± 91.3, p < 0.001 and p < 0.001). The transport function of the LA did not change significantly by TTE after the procedure. Fractional Area Change at baseline and 3 months was 33.9 ± 13.8 and 33.5 ± 10.7 p = 0.9 in the HPSD group while 38.1 ± 8.6 and 35.3 ± 12.2 p = 0.9 in the CB2 group. LA Ejection Fraction measured in the two groups (before and 3-month post-procedure): HPSD: 51.2 ± 20.5% and 49.5 ± 14.7%, p = 0.9, CB2: 49.7 ± 15.5% and 50.7 ± 13.3%, p = 0.8). Ablation time was comparable in the two groups (HPSD: 1676 ± 570 sec, CB2: 1495 ± 494 sec, p = 0.279), while fluoroscopy time and radiation exposure were significantly higher in the CB2 group (HPSD: 5.62 ± 4.31 min and 232 ± 406 cGycm2, CB2: 13.65 ± 5.18 min and 1819 ± 1669 cGycm2, p <0.001 and p <0.001). The LVA/LA surface ratio were: HPSD group: 8.37 ± 6.42% and CB2 group: 13.58 ± 8.92% (p = 0.007). At 12-month follow-up, the success rate, defined as freedom from AF/atrial tachycardia without antiarrhythmic drug was 80.1% (HPSD) and 84.2% (CB2) respectively. Conclusions The LA scar tissue was significantly higher following CB2 ablation, but did not affect medium-term efficacy. However, tissue loss did not reduce the transport function of the LA.