Changes over time in echocardiographic variables and atrial electromechanical intervals after ablation for atrial fibrillation

Abstract

IntroductionAcute and mid-term effects of ablation for atrial fibrillation (AF) on left atrial (LA) and left ventricular (LV) function and the atrial electromechanical interval are controversial. MethodsEchocardiographic variables and the PA-TDI interval (time from ECG lead II P-wave onset to lateral a′ wave on tissue Doppler tracings, indicating the total atrial conduction time [TACT]) were evaluated in 33 paroxysmal AF patients before, 1 day, and 3, 6, and 12 months after ablation. ResultsDuring a 12-month follow-up, 10 (30.3%) patients had recurrent AF, associated with a greater baseline LA volume (LAV) (48.4±19.3mm3 vs. 38.7±11.4mm3, P=0.0811) and PA-TDI interval (163.9±11.0ms vs. 151.1±14.6ms, P=0.0189) than in patients without AF recurrence. By 6 months after ablation, LAV had decreased progressively in the non-recurrence group (27.9±8.1mm3, P<0.0001 vs. baseline), but the decrease was modestly significant in the recurrence group (36.3±7.5cm3, P=0.0380). LV ejection fraction (LVEF) modestly increased 1 day after ablation in both groups and remained unchanged in the non-recurrence group (67.9±8.1% at baseline to 70.5±5.9% at 12 months, P=0.1711), whereas it decreased gradually below the baseline value in the recurrence group (68.2±11.3% to 60.9±13.6%, P=0.1025). The PA-TDI interval did not change during follow-up in either group, but remained longer in the recurrence group. ConclusionsThe PA-TDI interval may be useful for predicting post-ablation AF recurrences. The patterns of time-course changes in LAV, LVEF, and TACT differ, but the effects of ablation were better in patients without AF recurrence after ablation.