Differences in atrial electromechanical coupling and atrial volume in patients with idiopathic paroxysmal atrial fibrillation.

OBJECTIVES

The objective of the study was to evaluate the differences in atrial electromechanical coupling time and atrial volume between patients with idiopathic paroxysmal atrial fibrillation and control subjects and to investigate the influencing factors of electromechanical coupling time.

METHODS AND

RESULTS

We studied 46 patients with idiopathic PAF (group IPAF) and 62 control subjects (group N). Doppler tissue imaging data were performed to assess atrial electromechanical coupling.Atrial volumes were evaluated by acoustic quantification.The time intervals from the beginning of the P wave to the onset of atrial contraction motion at the interventricular septum atrioventricular annulus (P-A1), left lateral mitral annulus (P-A2) in group IPAF were significantly longer than in group N (P < 0.01). P-A2 was correlated positively with left atrial (LA) anterior-posterior dimension and the largest LA volume (r = 0.751, 0.689, P < 0.01) in the IPAF group.The longest duration of IPAF episodes was correlated with P-A2 (r = 0.652, P < 0.05).

CONCLUSIONS

There is a prolongation in the atrial electromechanical coupling from the onset of the P wave to the beginning of the backward motion of the mitral annulus and interventricular septum atrioventricular annulus in patients with idiopathic PAF. This prolongation may be affected by left atrial size and the longest duration of the IPAF episodes.