Learning Curve Analysis Of Cryoballoon Catheter Ablation For Atrial Fibrillation In Single-center

Objectives: To evaluate the efficacy,safety,and learning curve of cryoballoon catheter ablation(CBCA)for atrial fibrillation in single-center.Methods: A total of 90 AF patients,who were underwent CBCA approach,performed by a single performer in our center,were collected from January 2016 to July 2017.They were divided into the first generation balloon group and the second generation balloon group.The balloon diameter,radiofrequency catheter ablation(RFCA)supplement,times of freezing,freezing time,minimum balloon temperature,operation time,fluoroscopic time,immediately success rate,and complications were analyzed.In order to analyse the learning curve,the patients of both groups were arbitrarily divided into several groups according to the chronological order,and each group had 10 patients.Results: There was no significant difference in the choice of balloon diameter(P=0.156)and the proportion of RFCA filling points(P=0.434)between the two groups.The times of freezing and the total freezing time in the second generation balloon group were all shorter than those in the first generation balloon group(P<0.05).The minimum balloon temperature in the second generation balloon group was lower than that in the first generation balloon group during left superior pulmonary vein(LSPV)(P<0.05).The average operation time and fluoroscopic time of the second generation balloon group was shorter than the first generation balloon group [(60.40±19.94)min vs(93.20 ±22.82)min,P<0.001,(18.74±6.92)min vs(22.45±7.78)min],P=0.019).In the first generation balloon group,77.5% patients and 91.41% pulmonary veins were isolated successfully with CBCA alone.In contrast,in the second generation balloon group,the rate of acute PVI was 84% on patient level,and 93.97% on pulmonary vein level.There was no significant difference in complications between the two groups(P=0.448).Through the analysis of operative time,we found that the key groups of the learning curve were the first two groups in both first generation and second generation balloon goup.The key groups of the learning curve were not observed in the fluoroscopic time and the rate of acute PVI.Conclusion: Using CBCA approach for atrial fibrillation with high success rate,good safety and short learning curve.As a beginner,20 cases of cryoballoon catheter operation can be used to master the skills,shorten operation time and complete the learning curve.On the basis of the first generation balloon operation,the fluoroscopic time was shorter,and the immediately success rate can be obtained in the second generation balloon group.