Left atrial function after successful catheter ablation for paroxysmal atrial fibrillation: cryoablation versus radiofrequency techniques

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Purpose It has been suggested that cryoballoon (CB) ablation for paroxysmal atrial fibrillation (PAF) may lead to more extensive left atrial (LA) injury than radiofrequency (RF) ablation, however, results are conflicting. We sought to address this issue using modern echocardiographic techniques. Methods We performed transthoracic echocardiography in 90 patients (66% males, mean age 57 ± 10 years) successfully treated with RF (51%) or CB (49%) ablation for PAF before and 6 months after the procedure. Peak longitudinal LA strain (LAS) and strain rate (LASR) during the reservoir (r), conduit (cd) and contraction (ct) phases were measured during sinus rhythm by speckle tracking. The LA diameter and volume (LAV) index - using biplane area-length method divided by the body surface area were also calculated. Results The LA diameter decreased (38.1 ± 4.0 vs 37.2 ± 3.8 mm, p = 0.004), the LAV index did not change (33.5 ± 11.9 vs 34.4 ± 8.9 mL/m², p = 0.272) at 6 months in the whole study group. The LASRr and LASRcd increased, whereas there were no changes in remaining LA function parameters in either ablation strategy (table). The CB subgroup did not differ in LA function parameters comparing to RF subgroup at six months after procedure (table). Conclusion CB and RF ablation did not differentially affect the LA function. Successful ablation for PAF resulted in improvement of rate of deformation during reservoir and conduit LA cycle and stable contractile LA function. LA function parameters RF N = 46 (51%) CB N = 44 (49%) 6 months RF vs CB Parameter Baseline 6 months p Baseline 6 months p p* Global LASr [%] 27.7 ± 6.35 27.9 ± 6.0 0.833 27.9 ± 7.2 27.0 ± 6.4 0.370 0.539 Global LAScd [%] -14.6 ± 4.1 -14.8 ± 4.6 0.761 -15.3 ± 5.3 -14.1 ± 3.2 0.080 0.399 Global LASct [%] -13.0 ± 4.84 -13.0 ± 3.20 1.00 -12.6 ± 3.81 -12.9 ± 4.18 0.629 0.897 Global LASRr [sˉ¹] 1.18 ± 0.22 1.27 ± 0.26 0.046 1.07 ± 0.27 1.18 ± 0.30 0.041 0.141 Global LASRcd [sˉ¹] -1.11 ± 0.33 -1.25 ± 0.35 0.013 -1.07 ± 0.31 -1.16 ± 0.30 0.044 0.214 Global LASRct [sˉ¹] -1.46 ± 0.40 -1.50 ± 0.31 0.500 -1.42 ± 0.51 -1.39 ± 0.42 0.742 0.187 *p value corrected for baseline values