Abstract
PURPOSE: Spectral tissue Doppler-derived E/e' ratio has been proposed as the best parameter for prediction of atrial fibrillation (AF). Relaxation and contraction are equivalent parts of a continuous cardiac cycle, where systolic and diastolic abnormalities have a variable contribution to the left ventricle (LV) failure. The aim of this study was to investigate whether the E/(e'xs') ratio is a better index than E/e' to predict AF recurrence and to determine the changes of spectral tissue Doppler indices 1 month after the electrical cardioversion (ECV). PATIENTS AND METHODS: The study included 77 persistent AF patients with restored sinus rhythm (SR) after ECV. Only patients with normal LV ejection fraction (EF) were included. Echocardiography and NT-proBNP laboratory findings were performed. A primary outcome was the early (within 1 month) recurrence of AF. RESULTS: After a 1 month follow-up period, 39 patients (50.6%) were in SR. E/e' (HR=1.74, P=0.001) and E/(e'×s') ratios (HR=8.17, P=0.01) were significant predictors of AF recurrence. E/(e'×s') in combination with LV end-diastolic diameter >49.3 mm and NT-proBNP >2000 ng/L demonstrated a higher contribution in the model to predict AF recurrence compared to the E/e' ratio (18.94, P=0.005 vs 1.95, P=0.001). On ROC analysis, E/(e'×s') and E/e' showed similar diagnostic accuracy (E/(e'×s'), AUC=0.71, P=0.002 and E/e', AUC=0.75, P<0.0001). Average e' value significantly decreased after 1 month in SR (from 10.76±1.24 to 8.96±1.47 cm/s, P=0.01), E wave did not change significantly and E/e' ratio tended to improve. A decrease of average e' and an increase of average s' values led to significant improvement of E/(e'xs') ratio. CONCLUSION: E/(e'xs') and E/e' ratios are comparable to predict early AF recurrence after ECV in patients with persistent AF. The e' value decreased significantly after 1 month follow-up period after ECV for persistent AF patients.