Background and Objectives : The occurrence of atrial fibrillation(AF) after ablation of atrial flutter(AFL) is of clinical importance. We investigated the variables predicting this evolution in patients without a previous AF history after AFL ablation.
Materials and Methods : Thirty-six AFL patients(age; male, 28), without a previous AF history, who underwent conventional cavotricuspid isthmus ablation were enrolled in this study. Group 1(n=11) was defined as those who developed AF after AFL ablation during 1 year follow- up. Group 2(n=18) was defined as those who did not. The clinical variables and echocardiographic parameters were analysed and compared between the two groups. The left atrial(LA) size, ejection fraction(LVEF) and left atrial volume index(LAVI) were measured before and after ablation of AFL.
Results : No difference of clinical variables between the two groups was observed. The preablation LVEF(preLVEF) and postablation LVEF(postLVEF) were 54±14% and 56±13% respectively in group 1 patients, and 47±16% and 52±13% respectively in group 2. The difference of LVEF change before and after ablation between two groups were statistically not significant( 2.2±1.5% in group 1 vs. 5.4±9.8% in group 2, p=0.53). The preablation LA size(preLA) and postablation LA(postLA) are 40±4mm and 41±4mm respectively in group 1 and 44±8mm and 41±4mm respectively in group 2. The degree of change of LA size before and after AFL ablation in two groups were statistically not significant(0.6±0.9mm in group 1 vs -3.8±7.4mm in group 2, p=0.149). The left atrial volume index(LAVI) was increased after ablation in group 1(from 32±10mm3/m2 to 35±10 mm3/m2, p=0.078). The LAVI was decreased after ablation in group 2 patients, which was also statistically not significant(from 32±10 mm3/m2 to 29±8 mm3/m2, p=0.234). However, there were a significant reduction of LAVI in group 2 patients( mean ΔLAVI= -3.8±7.4, p<0.05 ), compared to that of group 1(mean ΔLAVI= 0.6±0.9).
Conclusion : The reduction of LAVI after AFL ablation is the robust predictor of occurrence of AF after AFL ablation in patients presented primarily with AFL and no documented evidence of AF.
|
