Abstract 3069: Reduction of Left Ventricular Dyssynchrony after Catheter Ablation for Isolated Permanent Atrial Fibrillation in Patients with Depressed Left Ventricular Function
Background: Persistent/Permanent atrial fibrillation (Per AF) and electromechanical left ventricular (LV) dyssynchrony are frequently associated in patients with systolic heart failure. Their relationships have not been investigated yet. Objective: We hypothesized that Per AF could induce or worsen ventricular dyssynchrony. The aim of this prospective study was
to evaluate the degree of LV dyssynchrony in patients with Per AF and depressed LV function;
to describe the evolution of dyssynchrony after AF catheter ablation.
Methods: 28 patients with isolated Per AF and depressed LV function were investigated with a VIVID7 (General Electric) before ablation (D-1), at 1 month (M+1) and at 6 month (M+6) after the procedure and compared to 28 controls. LV ejection fraction was evaluated by biplane Simpson rule. LV dyssynchrony was quantified by tissue Doppler imaging in apical views using a triplane 3D/4D acquisition. Maximal difference between times to peak (mdTP) was determined. TP was measured as the delays between the onset of the QRS and the peak velocity of systolic wave on the 6 basal LV segments. Values were averaged on 3 consecutive cardiac cycles. LV dyssynchrony was defined for a mdTP value >65ms. Parameters of dyssynchrony were normalized to RR interval.
Results: Before ablation, mdTP was >65ms for 10 (36%) of the patients (group1) and >65ms for 18 patients (group 2). Ejection fraction was significantly lower in group 1 than in group 2. During the follow-up, the LV ejection fraction increase was similar in the 2 groups (+42%; +41%)(Table⇓). In the whole population, mdTP decreased from 57.5±35ms to 44.1±35ms (P<0.05). However, the LV dyssynchrony improvement was much more marked in group 1 than in group 2 (−42%; −13%).
Conclusions: In this study, LV dyssynchrony was present in 36% of the patients with permanent AF and impaired LV ejection fraction. Catheter ablation significantly improved both LV ejection fraction and LV dyssynchrony in this population.