Abstract 15303: The Disappearance of ‘Double Peak Sign’ With Tissue Doppler Imaging After Radiofrequency Catheter Ablation in Patients With Atrial Fibrillation
Electromechanical conduction time (EMT) based on tissue Doppler imaging has been reported as a predictor of atrial fibrillation (AF) recurrence. A double peak mitral annular velocity was sometimes observed in AF patients after successful catheter ablation, however it’s clinical significance is still in question.
Methods: Forty-five consecutive AF patients (Age, 62 yrs) undergoing catheter ablation were enrolled. After successful ablation, the atrial activation time was measured by a three-dimentional mapping system. Echocardiography was performed within 24 hours and 6 months after the procedure. Tissue Doppler-based EMT-a’ was defined as the time interval from P wave onset to the highest late diastolic velocity in the lateral mitral annulus. Cases with higher a’2 velocity than a’1 velocity were defined as having ‘double peak sign’. Speckle tracking-based EMT-ε was also measured as a reference (Figure).
Results: The mean left atrial volume, left ventricular ejection fraction, atrial activation time, EMT-a’ and EMT-ε were 64ml, 63%, 99ms, 206ms and 210ms, respectively. The atrial activation time showed close correlations to the EMT-a’ (R2= 0.30, P< 0.001) and EMT-ε (R2= 0.34, P< 0.0001). During the 6 months follow-up, left atrial booster and reservoir function were significantly improved in parallel with left atrial volume reduction. The proportion of patients having ‘double peak sign’ decreased by half during the follow-up (42% vs 20%, P< 0.01).
Conclusions: ‘Double peak sign’ based on tissue Doppler imaging is considered to be a sign of atrial delayed mechanical contraction.
- © 2013 by American Heart Association, Inc.