Abstract 19826: Utility of Stroke Volume Index for Stratification of Patients With Low Gradient Severe Aortic Stenosis and Normal Left Ventricular Ejection Fraction
Background: Decision of intervention for low gradient severe aortic stenosis (AS) with normal left ventricular ejection fraction (LVEF) is clinically challenging. The study was to determine the impact of stroke volume index (SVi) on prognosis in patients (pts) with AS.
Methods: We examined 410 pts with moderate or severe AS and normal EF (≥50%). Pts were divided into four groups based on aortic valve area (AVA), mean pressure gradient (MPG) and SVi: Group I: low flow low gradient severe AS (AVA≤1.0cm2, MPG<40mmHg and SVi<35mL/m2, n=75); Group II: normal flow low gradient severe AS (AVA≤1.0cm2, MPG<40mmHg and SVi≥35mL/m2, n=97); Group III: severe AS with matched gradient-AVA (AVA≤1.0cm2 and MPG≥40mmHg, n=88); Group IV: moderate AS (AVA>1.0cm2 and MPG>20mmHg, <40 mmHg, n=150). Aortic valve gradients, AVA and SVi were assessed by echocardiography. Clinical charts were reviewed. Mean follow-up duration was 3.2±1.6 years.
Results: Group I had higher prevalence of atrial fibrillation, more pronounced LV hypertrophy, lower SVi, smaller AVA, higher valvuloarterial impedance (Zva) (Table) and lower 3-year cumulative survival compared to Group II and Group IV (61% vs. 75% and 80%, p=0.004). Group II had a 3-year cumulative survival similar to moderate AS (75% vs. 80%, p>0.05). In pts with medical management, Group I and Group III had lower 3-year cumulative survival in comparison with Group II and Group IV (48% and 56% vs. 73% and 76%, p=0.001). Multivariate analysis showed SVi was a strong predictor of mortality in low gradient severe AS (HR 0.95, CI: 0.91-0.99, P=0.02). However, in gradient-AVA matched severe AS and moderate AS, SVi was not associated with mortality (p>0.05).
Conclusions: Without AS intervention, low flow low gradient severe AS with normal EF carries poor prognosis similar to high gradient AS, but normal flow low gradient AS does not, suggesting that SVi may be used to identify the pts benefiting most from AS intervention in pts with low gradient AS.
Author Disclosures: H. Shen: None. B. Stacey: None. B. Applegate: None. D. Zhao: None. S. Vasu: None. B. Upadhya: None. S. Gandhi: None. R. Liu: None. M. Wei: None. M. Pu: None.
- © 2015 by American Heart Association, Inc.