Abstract 16418: The Impact of MitraClip® Procedure on Left Atrial Strain and Strain Rate
Background: Left atrial (LA) remodeling due to mitral regurgitation (MR) is associated with abnormal LA strain parameters which may correlate with degree of fibrosis. Although reverse atrial remodeling has been shown after MitraClip placement, changes in LA strain and strain rate have not been evaluated in these patients or compared with mitral valve repair (MVr).
Methods: We measured peak positive LA strain (ε) and strain rates [peak systolic (SRp), peak early diastolic (SRe) and peak late diastolic (SRa)] in 107 subjects (mean age 61±12 yrs) with degenerative MR enrolled in the randomized EVEREST II trial. Individuals with paced rhythm, atrial fibrillation, functional MR and poor image quality were excluded. LA strain measures were obtained from 4-chamber and 2-chamber views and averaged at baseline and at 1 year follow up.
Results: At one year all 44 MVr subjects had ≤2+ MR, whereas 22 of the 63 MitraClip had >2+ MR. Baseline average ε, SRp, SRe and SRa values were similar in MitraClip and MVr groups (Table 1). At one year follow up there was a significant decrease in LA volumes in the surgical group and in those with MR ≤2+ after MitraClip. Overall average ε was significantly reduced after MVr. There was a small decrease or no change in average ε after MitraClip. SRe was significantly decreased 1 year after MVr and also in the MitraClip arm, regardless of whether there was significant MR reduction. There were no changes in SRp and SRa at 1 year in either group.
Conclusion: Average peak positive LA strain either decreased modestly or did not change after treatment of MR in chronic degenerative MR subjects. There was a significant decrease in SRe in both treatment arms at 1 year. This occurred despite evidence of reverse LA remodeling. Further investigation and replication in additional cohorts is needed to explore these findings, which may suggest persistence of LA dysfunction after correction of chronic MR, or irreversible fibrosis.
Disclosure: EVEREST II was funded by Abbott Vascular.
Author Disclosures: E. Gucuk Ipek: None. A. Qasim: None. E. Viloria: None. T. Feldman: Research Grant; Significant; Dr. Feldman has received honoraria/institutional research support from Abbott, Boston Scientific, Edwards and WL Gore. P.A. Grayburn: Research Grant; Significant; Dr. Grayburn has received grants from Abbott Vascular, Medtronic, Baxter, ValTech Cardio, Guided Delivery Systems and consulting fees/honoraria from Abbott Vascular, Tendyne and Bracco Diagnostics. E. Foster: Research Grant; Significant; Dr. Foster has received a research grant from Abbott for the Evalve and EVEREST II studies..
- © 2014 by American Heart Association, Inc.