Abstract 18816: Deterioration in Left Atrial Strain After Repeated Pulmonary Vein Isolation for Atrial Fibrillation - A Two-Dimensional Speckle Tracking Study
Background: The effect of pulmonary vein isolation (PVI) for atrial fibrillation (AF) on left atrial (LA) phasic function is currently unknown. LA strain imaging by 2-dimensional speckle tracking is a novel methods that may provide insight into the changes of LA phasic function post-PVI.
Methods: Transthoracic echocardiograms and speckle tracking (GE, Vivid 7) were performed before and after PVI in 11 patients with paroxysmal AF (age 61±8, 27% female). Five of the patients have had prior PVI. All scans were performed while in sinus rhythm. LA phasic function was assessed by peak negative and positive LA strain (εneg, εpos), corresponding to atrial systole and diastole respectively; and positive, early negative, and late negative LA strain rates (SR+ve, SRearly-ve, SRlate-ve), corresponding to LA reservoir, conduit, and contractile functions respectively.
Results: Changes in strain and strain rates after PVI were different in patients who have had prior PVI vs. those who have not. In those who had prior PVI, εneg and SR+ve deteriorated significantly after repeat PVI (p=0.036 and 0.017 respectively), indicating worsened LA contractile and reservoir functions. In those who did not have prior PVI, SR+ve improved significantly after PVI (p=0.025). Comparing the two groups, the observed changes in atrial contractile (εneg, SRlate-ve) and reservoir (SR+ve) functions post-PVI were significantly different between the two subgroups. (Table 1)
Conclusion: In this small pilot study, LA strain imaging by speckle tracking demonstrated deterioration in atrial contractile and reservoir functions in those who had repeat PVIs vs. those undergoing PVI for the first time. This phenomenon may reflect atrial myocardial scarring with repeated ablation and speckle tracking may be a useful technique for such assessment.
- © 2010 by American Heart Association, Inc.