Pulmonary Vein Isolation And Its Predictors In The First Step Cryoballoon Ablation Of The "ICE Plus FIRE" Ablation In Patients With Atrial Fibrillation

Background:There is not yet a theory or hypothesis can explain the trigger and maintain mechanisms of atrial fibrillation perfectly, pulmonary vein isolation ablation is still the cornerstone of the treatment of atrial fibrillation. So far, cryoballoon ablation and radiofrequency catheter ablation both are the most widely used clinical ablation mode. Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, originally use both cryoballoon ablation and radiofrequency ablation during procedure in the treatment of atrial fibrillation, which is called "ICE plus FIRE" ablation. By analyzing baseline and intraoperative data, the study discusses the effectiveness of pulmonary vein isolation and its predictors.Method:The study enrolled 49 patients with drug refractory atrial fibrillation, make statistical comparison of each pulmonary vein isolation in the cryoballoon procedure. According to the significant difference between each pulmonary vein isolation, we compare the right inferior pulmonary vein with the other three pulmonary veins about the intraoperative data. Then, patients are divided into two groups depending on whether pulmonary vein is isolation, we make statistical analysis of various factors that may affect pulmonary vein isolation. Meanwhile, discuss the safety of cryoballoon ablation and observe whether related complications happend.Result:After the first step cryoballoon ablation, the rate of each pulmonary vein isolation shows below:left superior pulmonary vein 65%(32 cases), left inferior pulmonary vein 53%(26 cases), right superior pulmonary vein 53%(26 cases), right inferior pulmonary vein 20%(10 cases), in which the right inferior pulmonary vein isolation success rate is significantly lower than left superior pulmonary vein (P<0.001), left pulmonary vein (P=0.001) and right superior pulmonary vein (P=0.001), and the right inferior pulmonary is also significantly different with other three pulmonary veins in warming time (P<0.05). In addition, the unisolated group of left inferior pulmonary vein’s creatinine level (89 ±18 umol/L) is significantly higher than the isolation group (79 ± 12 umol/L), P=0.016; the unisolated group of right superior pulmonary vein includes more patients with persistent atrial fibrillation (4 cases,17%) than the isolation group (0 cases,0%), P=0.046.Conclusion:In the first step cryoballoon ablation of "ICE plus FIRE" ablation, the rate of right inferior pulmonary vein isolation is significantly lower than the left pulmonary vein, the left pulmonary vein and the right superior pulmonary vein; Persistent atrial fibrillation and high preoperative creatinine level may be associated with the failure of pulmonary vein isolation among the cryoballoon ablation.