Abstract 14840: Regional changes in Left Ventricular function and geometry - Transcatheter Aortic Valve Implantation versus Surgical Aortic Valve Replacement.
Introduction Aortic Stenosis (AS) produces a pressure overloaded left ventricle (LV). Initial hypertrophy leads to eventual diastolic and systolic dysfunction. Transcatheter Aortic Valve Implantation (TAVI) and Surgical Aortic Valve Replacement (SAVR) have been shown to reverse remodel LV mass and volumes but the regional effects of TAVI on the LV wall are unknown. We used Cardiovascular Magnetic Resonance (CMR) to accurately measure global and regional LV geometry and wall function (thickness, thickening and wall motion) before and after TAVI and SAVR.
Methods Forty patients (20 TAVI/20 SAVR) completed baseline and 6 month 1.5T CMR scans. Analysis was performed by 2 experienced observers blinded to the clinical details. Epicardial and endocardial borders were contoured (QMass V7.2; Medis) on a LV short axis stack (10mm slices, 0mm gap) with segmentation of regions according to the AHA 16 segment model.
Results Globally, end-diastolic wall thickness (EDWT) and end-systolic wall thickness (ESWT) decreased after 6 months for both groups. LV systolic wall thickening (SWT) and wall motion (WM) significantly improved after TAVI but not after SAVR (Table 1). On regional analysis, out of a potential 16 segments TAVI significantly improved (p0.05) of all four parameters post-TAVI. SAVR improved regional wall function in only 5, 1, 3 and 0 segments (EDWT, ESWT, SWT and WM respectively).
Conclusion TAVI significantly improves global and regional LV wall function at 6 months. However, in SAVR treated patients there was no improvement in global SWT or WM, and fewer changes of regional function. Regional analyses demonstrated that post-TAVI the basal septal wall had less functional improvement for all measures. This corresponds with the area of greatest preoperative hypertrophy and may reflect an area of fibrosis with less potential for remodelling.
- © 2011 by American Heart Association, Inc.