Abstract 11741: Severe Aortic Stenosis With Normal Left Ventricular Ejection Fraction, Normal Flow and Low Gradients. Another Paradox or Only Moderate Stenosis?
Background: Among the 4 hemodynamic subsets of severe AS with preserved EF, based on LV stroke volume index (SVi) and mean pressure gradients, normal flow with a low gradient (NF/LG) has been attributed to measurement errors, small body size or inconsistencies in guideline criteria and associated with a favorable prognosis. We hypothesized that AV weight (AVW) in NF/LG AS, would be lower than that in other hemodynamic groups.
Methods: Between 2010-13, 403 consecutive patients (pts) undergoing AV replacement (AVR) for severe isolated AS, (mean age 76.8 (9.3) yrs, 56% men, AVA index 0.36 (0.10 cm2)/m2, EF = 61.3 ± 4.6%, 11% bicuspid valves, mean follow-up 18 ± 9 months), underwent intraoperative TEE and had the AV weighed after excision (AVW = 2.4 ± 0.9 g), and excised valves were collected in formaldehyde, dried and weighed. All echo variables were measured off-line by a single observer on a dedicated reading station (Agfa). Medical records were reviewed to extract clinical data and all-cause mortality determined from the Social Security Death Index. Analysis of covariance (ANCOVA), Chi-square test, and Cox proportional hazards regression models were used as appropriate.
Results: (for unadjusted comparisons see table.) In models adjusted for age, gender BSA, EF and annular area, AVW and AVW index remained lower in NF/LG than that in the high gradient groups (p<.01 for both). Although the number of deaths was small, no significant difference in all-cause mortality or time from AVR to death was found among the 4 groups (p=0.27 and p=0.28, respectively). AVR improved survival to a similar degree regardless of hemodynamic phenotype.
Conclusions: 1. Compared with high gradient groups, pts with normal flow-low gradient have a lower AVW and AVW/aortic annulus area, a lower severity of stenosis and less LV remodeling. 2. These findings support the recent recommendation to categorize these pts as having only moderate AS.
Author Disclosures: D. Alexandru: None.
- © 2014 by American Heart Association, Inc.