Effect of Catheter Ablation for Isolated Paroxysmal Atrial Fibrillation on Longitudinal and Circumferential Left Ventricular Systolic Function

Abstract

Isolated paroxysmal atrial fibrillation (AF) is commonly associated with left ventricular (LV) diastolic dysfunction but normal radial systolic contraction. We aim to investigate LV systolic function more precisely using 2-dimensional strain technique in patients with isolated paroxysmal AF and to evaluate evolution of longitudinal, circumferential, and radial (or transverse) strain components after catheter ablation of AF. Thirty patients with isolated paroxysmal AF were investigated by echocardiographic studies before and at 1-day, 1-month, 6-month, and 12-month intervals after radiofrequency ablation. Left heart dimensions and LV systolic and diastolic functions were evaluated at each time interval. LV systolic function was quantified by LV ejection fraction and by 2-dimensional strain evaluation, giving regional and global longitudinal, circumferential, transverse, and radial peak of percentage deformation. Patients with AF were compared with 30 control subjects, paired by age and by sex. Before AF ablation, LV ejection fraction, transverse and radial strains were not significantly different from control subjects. By contrast, global longitudinal and circumferential strains were significantly lower than controls (-17.7%+/-2.4% vs -21.5%+/-2.0% [p<0.01] and -16.0%+/-2.9% vs -20.7%+/-3.4% [p<0.01], respectively). At the end of follow-up, global longitudinal and circumferential strains were significantly improved (-20.8%+/-2.6% vs -17.7%+/-2.4% (p<0.01) and -18.5%+/-3.1% vs -16.0%+/-2.9% [p<0.05], respectively). Global longitudinal strain was not significantly different from normal control subjects at the end of follow-up. In conclusion, this prospective study demonstrates (1) the existence of early longitudinal and circumferential LV systolic function abnormalities in patients with isolated paroxysmal AF but normal ejection fraction and (2) reverse remodeling of these abnormalities after AF ablation.