Background: Acute atrial fibrillation (AF) is often treated with the administration of intravenous flecainide; however, this treatment may not always be successful and is potentially hazardous. Previous studies suggest that electro-echocardiographic tissue velocity imaging (TVI) of the atrial wall may reflect atrial remodeling.
Objective: To study whether atrial TVI can be used to identify nonresponders of flecainide administered intravenously in patients with acute AF.
Methods: We used atrial TVI to measure atrial fibrillatory cycle length determined by using tissue velocity imaging (AFCL-TVI) and atrial fibrillatory wall motion velocity determined by using tissue velocity imaging (AFV-TVI) in the left atrium in 52 (55%) patients presenting with acute AF in the emergency department. These 2 parameters reflect electrical and structural remodeling, respectively. Standard baseline characteristics were recorded.
Results: Patients were predominantly men (76%) and 64 ± 11 years old. Thirty-six (69%) patients had successful cardioversion after flecainide infusion. There were no significant differences in baseline characteristics between responders and nonresponders. Patients with a successful cardioversion had a longer mean AFCL-TVI and higher median (interquartile range) AFV-TVI compared with patients with failed cardioversion: 172 ± 29 ms vs 137 ± 35 ms (P < .001) and 4.2 (3.3-6.2) cm/s vs 2.3 (1.9-3.5) cm/s (P = .001).
Conclusions: Electro-echocardiographic atrial TVI measurement is a promising noninvasive tool for predicting outcome of pharmacological cardioversion. A short AFCL-TVI and a low AFV-TVI are related to failure of cardioversion of AF using flecainide.
Keywords: Atrial fibrillation; Echocardiography; Flecainide; Pharmacological cardioversion; Tissue Velocity Imaging.
Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.