Interatrial dyssynchrony on tissue Doppler imaging predicts progression to chronic atrial fibrillation in patients with non-valvular paroxysmal atrial fibrillation.

OBJECTIVE To determine prospectively whether interatrial dyssynchrony detected by tissue Doppler imaging (TDI) is useful for predicting the progression to chronic atrial fibrillation (CAF) in patients with non-valvular paroxysmal AF (PAF). METHODS Thirty-seven patients with non-valvular PAF were prospectively followed after echocardiography. The interval of time from initiation of the P wave on the electrocardiogram (ECG) until the beginning of the late diastolic TDI signal at the lateral border of the mitral annulus (P-A'(M)) and the tricuspid annulus (P-A'(T)) was measured. Interatrial dyssynchrony was defined as the difference between the P-A'(M) and P-A'(T) intervals (A'(M)-A'(T)). The study endpoint was the onset of CAF (>6 months). RESULTS During a follow-up period of 28 (SD 23) months, eight patients developed CAF. Compared with those without CAF, the patients who developed CAF had a significantly lower atrial systolic mitral (A'(M)) (7.7 (1.7) vs 10.7 (2.9) cm/s, p<0.01) and tricuspid (A'(T)) (12.9 (3.5) vs 16.6 (5.1) cm/s, p<0.05) annular tissue Doppler velocity, as well as a longer A'(M)-A'(T) interval (47 (13) vs 24 (10) ms, p<0.0001). Kaplan-Meier analysis, using cut-off values determined by analysis of receiver-operating characteristics curves, revealed that progression to CAF was significantly more frequent when the A'(M)-A'(T) interval was > or =34 ms (p<0.01), the A'(M) velocity was < or =9 cm/s (p<0.05) and the A'(T) velocity was < or =16 cm/s (p<0.05). CONCLUSIONS This prospective study suggests that non-valvular PAF patients with a high risk of developing CAF have "interatrial dyssynchrony" and "atrial systolic dysfunction" on atrial TDI.