Effect Of Radiofrequency Ablation In Atrial Fibrillation On The Ion Channel Protein And Current Remodeling

Objective:To study the effect of radiofrequency ablation (RFA) on atrial electrical remodeling, ion flow rebalancing and reverse remodeling, and try to find possible target miRNAs which can guide early diagnosis and intervention of atrial fibrillation (AF).Methods:The Peripheral blood (PB) were taken from 30 AF patients in AF group before and after RFA 3 months, in which included patients with 10 paroxysmal,10 persistent and 10 permanent AF, and 10 healthy subjects in control group. The circulating miRNAs expression profile difference in whole genome was detected with the microRNA chips (microRNA v 18.0), analyzed with Volcano Plot and tMEV software respectively, and further validated by Real-time PCR. Furthermore, the target gene of miRNAs was predicted through the Mirbase, Miranda and Targetscan databases.Results:The miRNAs expressions profile Before RFA were significantly different in AF group compared with control group (P<0.05), and also tremendously different compared with which of the patients themselves before and after RFA of 3 months. The main 21 miRNAs regulating ion channel protein including SCN5A, CACNA1C, KCNA5, KCNH2, KCNE1, KCNQ1, KCNJ2, KCNC4, KCND3, KCNN3, HCN1, HCN3 and HCN4, there were 5 ones which was up-regulation before RFA, but down-regulation after RFA of 3 months including miR-1266 etc. Oppositely, others were down-regulation before RFA, while up-regulation after RFA of 3 months significantly excluding only miR-3664-5p down-regulated 8.88 times before RFA, and further down-regulated 46.06 times after RFA 3 months. Especially, miRNAs regulating Out-flowing K+ ion channel protein, such as KCNA5, was that the regulating tendency was unanimous, and adjusting amplitude was larger before and thereafter RFA.Conclusion:RFA can change the expressions of miRNAs regulating the ion channel proteins, rebalance and reverse the ion current remodeling of AF. miRNAs which can simultaneously regulate multiple ion channels, such as miR-1266 etc., may become the future targets for AF intervention.