Left Atrial Function Assessed by Doppler Echocardiography Rather Than Left Atrial Volume Predicts Recurrence in Patients With Paroxysmal Atrial Fibrillation

BACKGROUND: Paroxysmal atrial fibrillation (PaAF) may present as a single self-terminating episode of atrial fibrillation (AF) or a more persistent form after sinus conversion. We investigated predictors of recurrence in patients with PaAF. HYPOTHESIS: Left atrial function would be an useful parameter for predicting PaAF recurrence. METHODS: The study population included 228 PaAF patients (131 males, age 64±14 years) who underwent transthoracic echocardiography immediately after spontaneous sinus conversion at initial AF diagnosis. We followed the study patients for AF recurrence. RESULTS: AF recurrence was demonstrated in 45 patients (20%, age 68±13 years) after spontaneous sinus conversion. Patients with recurrence had larger left atrial volume index (32±12 vs 25±10 mL/m2, P<0.001), left ventricle mass index (107±34 vs 93±25 g/m2, P=0.012), and left ventricle filling pressure (E/e'') (14±7 vs 12±5, P=0.012), whereas early diastolic mitral annular velocity (e') (5±2 vs 6±3 cm/s, P=0.021), late diastolic mitral annular velocity (A') (7±3 vs 9±2 cm/s, P<0.001), and peak systolic mitral annular velocity (7±2 vs 8±2 cm/s, P=0.045) were significantly lower. In multivariate Cox regression analysis detecting independent predictors of PaAF recurrence, lower A' (hazard ratio: 0.623, 95% confidence interval: 0.476-0.815, P=0.001) was a significant predictor of AF recurrence. CONCLUSIONS: A', which indicates left atrial (LA) contractile function after sinus conversion, was the independent predictor of PaAF recurrence, whereas LA volume was not. LA function may be more important than LA volume in predicting recurrence particularly in patients with PaAF.