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.