Left atrial appendage function after internal atrial defibrillation

To determine the value of echocardiographic parameters for predicting maintenance of sinus rhythm after internal atrial defibrillation (IAD), transthoracic and transesophageal echocardiography were performed in 38 patients with atrial fibrillation (AF) before IAD. In addition, serial echocardiographic examinations were performed at 1, 7, and 28 days after IAD in 20 patients to assess the effect of IAD on echocardiographic markers of thromboembolic risk. AF had recurred in 49% of patients within 6 months following IAD. Left atrial chamber and appendage size and ejection fraction were not predictive of recurrence of atrial fibrillation. However, peak emptying velocities of the left atrial appendage were significantly lower in patients with recurrence of atrial fibrillation as compared with patients who had maintained sinus rhythm (0.26 +/- 0.1 m/sec vs 0.49 +/- 0.17 m/sec; P = 0.001). A peak emptying velocity < 0.36 m/sec had a sensitivity of 82% and specificity of 83% for predicting the recurrence of AF. Peak A wave velocities increased gradually after cardioversion from 0.47 +/- 0.16 m/sec at 24 hours to 0.61 +/- 0.13 m/sec after 7 days (P < 0.05). One patient developed a new thrombus in the left atrial appendage and another patient suffered a thromboembolic event after IAD. Assessment of left atrial appendage function adds information regarding the probability of maintaining sinus rhythm after the procedure and the need for anticoagulation therapy with IAD.