Abstract 17534: Predictors of Progression of Aortic Valve Stenosis in Medically Treated Patients With Low-Flow Significant Aortic Stenosis
Background and Aims: The progression of aortic valve stenosis (AS) in patients with the paradoxical low-flow state despite preserved left ventricular ejection fraction (LVEF) has not been previously studied. We aim to determine its predictors in medically treated patients.
Methods: We studied 153 consecutive patients with low-flow (stroke volume index, SVI <35 mL.m-2) moderate to severe AS (indexed aortic valve area, AVAI 50%) who underwent paired echocardiographic studies >180 days apart. Besides conventional echocardiography, valvuloarterial impedance (Zva), a measure of global left ventricular afterload, was calculated. There were 49 patients (32%) with a significant (>20%) decrease in AVAI (Group A). We compare their baseline clinical and echocardiographic parameters to the group without deterioration (Group B).
Results: The mean time interval between paired studies is 909±834 days. Over this period, the mean AVAI decreased from 0.62 to 0.45 cm2.m-2 (p<0.001) in group A but remained similar in group B. LVEF fell by 4% in both groups. The mean age (71±12 years) and proportion of males (40%) were similar between the two groups. The prevalence of diabetes (52% vs. 33%, p=0.033) was higher in group A, while both groups had similar prevalence of hypertension (69%), hyperlipidemia (41%), chronic kidney disease (17%) and ischemic heart disease (30%). Left ventricular volumes, wall stress and Zva were similar between the two groups. Lower initial AVAI and dimensionless index, as well as higher transaortic resistance were associated with subsequent deterioration in AVAI. However, transaortic gradients were not predictive (Table).
Conclusion: Low-flow AS patients with preserved LVEF, smaller AVAI and higher prevalence of diabetes tended to progress more rapidly. They may benefit from more intensive follow-up as well as optimal timing of valve replacement.
- © 2013 by American Heart Association, Inc.