Time interval from the initiation of the electrocardiographic P wave to the start of left atrial appendage ejection flow: A novel method for predicting atrial fibrillation recurrence.

OBJECTIVE: The incidence of paroxysmal and persistent atrial fibrillation (AF) recurrence is high and unpredictable. In this study, a novel noninvasive method that was thought to reflect the interatrial conduction time was investigated to predict AF recurrence. This method was on the basis of the measurement of time interval from initiation of the electrocardiographic P wave to the start of left atrial (LA) appendage (LAA) ejection flow (P-LAA).

METHODS AND RESULTS: Forty-five consecutive patients (age, 61 +/- 11 years; 20 male) with newly diagnosed AF (mean duration, 132 hours; range: 6 hours-3 months) who converted to in sinus rhythm spontaneously or with cardioversion were studied prospectively. Transthoracic and transesophageal echocardiography were performed to measure LA size, mechanical functions, LAA ejection velocity, and P-LAA. Transesophageal echocardiography was performed for the measurement of P-LAA 1 to 2 days after conversion to in sinus rhythm. The patients were followed up for a period of 163 +/- 72 days for the recurrence of AF. AF recurred in 17 (38%) patients after a mean time of 81 +/- 67 days. P-LAA was significantly higher in patients with AF recurrence (123 +/- 36 vs 92 +/- 24 milliseconds, P =.0047) and multiple regression analysis indicated that P-LAA was an independent predictor of AF recurrence. Multiple regression analysis revealed no significant differences in LA size parameters, or in clinical and LA mechanical function parameters recorded after restoration of in sinus rhythm between patients with and without AF recurrence.

CONCLUSION: P-LAA may be considered to be an independent predictor of recurrent AF.