Correlation analysis on QT prolongation and hypertension combined with atrial fibrillation after radiofrequency catheter ablation

doi:10.3760/cma.j.issn.1673-4777.2014.04.001

Abstract：Objective To determine whether prolongation of QTc interval predicts atrial fibrillation (AF) recurrence after catheter ablation in a cohort of patients with hypertension.Methods We retrospectively enrolled 242 hypertensive patients with AF who underwent the first time catheter ablation procedure in Beijing Anzhen hospital,all patients were divided into relapse group (98 cases) and no relapse group (144 cases) according to disease relapse.Baseline data and QTc before procedure were collected.Results 98 patients had AF recurrence after a mean follow-up of (17 ± 9) months.Those experiencing recurrence had longer QTc than those who did not experience recurrence[(419 ±23)ms vs (429 ±26) ms] (P =0.004).Left atrial diameter(LAD) of relapse group was larger than that of no relapse group [(41 ± 6) mm vs (38 ± 5)mm] (P =0.003).There were significant correlation between QTc and heart rate (r =0.162,P =0.011).Recurrence of AF after catheter ablation of long QTc group(n =53) were higher than that of normal QTc group (n =165) and short QTc group (n =24) (P =0.001,P =0.069).Compare on recurrence of AF after catheter ablation between the group with LAD ＜ 38.3 mm and the group with LAD ≥38.3 mm,left atrial enlargement was associated with recurrence after catheter ablation (P =0.017).Multivariate Cox regression analysis demonstrated that QTc and LAD were independent predictors for recurrence of AF [QTc:hazard ratio(HR) =2.361,95％ CI:l.353-4.121,P =0.003 ;LAD:HR =1.795,95％ CI:I.041-3.094,P =0.035].The patients with longer QTc was associated with an increased risk of AF recurrence (HR:2.361,95％ CI:1.353-4.121,P =0.003).QTc had an incremental value over LAD in predicting AF recurrence after catheter ablation.Conclusion QT prolongation is an independent risk factor for AF recurrence after catheter ablation in patients with hypertension.