Abstract: Objective To evaluate the changes of function and structure of left and right atrium and brain natriuretic peptide(BNP) level after radiofrequency catheter ablation(RFCA) in patients with idiopathic and frequent ventricular premature contractions(VPCs) of different origins before and after operation, and to explore the impact of RFCA on left and right atria of patients with normal cardiac function and VPCs of different origins. 
Methods A total of 62 inpatients undergoing successful RFCA in the Second Hospital of Hebei Medical University were enrolled, and divided into left ventricle origin group and right ventricle orgin group. Two-dimensional echocardiographic speckle tracking technology was used to observe the left atrial diameter(LAD), right atrial ejection fraction(RAEF) and left atrial ejection fraction(LAEF) before and at 1 day, 1 month, 3 months, and 9 months after RFCA, and BNP detection was performed. The relevant data were compared within and between groups. 
Results The indicators in both groups were increased except BNP, as compared with those before operation. Strain(S) and strain rate(SR) of the left atrium after operation were significantly better in the right ventricle origin group than in the left ventricle origin group. The S and SR of the right atrium in the left ventricle origin group was significantly higher than those of the right ventricle origin group, however, the two groups were only statistically significant at different time points(P＜0.05). No significant difference was found in interaction between groups, and time points between groups(P＞0.05). After operation, BNP in right ventricle origin group and left ventricle origin group was decreased gradually. 
Conclusion After RFCA treatment of simple VPCs, the recovery of left atrial function of the right ventricle origin group was more obvious than that of the left ventricle origin group, and the recovery of right atrial function of the left ventricle origin group was more significant than that of the right ventricle origin group. After effective treatment of VPCs by RFCA, the plasma BNP was reduced. It may be of significance to use BNP to judge the severity and development of patients with VPCs when the cardiac function or structure changes are not obvious by echocardiography.

Key words: cardiac complexes, premature, natriuretic peptide, brain, catheter ablation