Prognostic Implications of Left Ventricular Ejection Fraction Across the Flow-Gradient Patterns in Severe Aortic Stenosis.

Background

Current guidelines classify normal-flow low-gradient (LG) aortic stenosis (AS) with left ventricular ejection fraction (LVEF) ≥50% as "moderate." However, the prognostic impact of LVEF remains incompletely understood across various hemodynamic subtypes of AS.

Methods

We analyzed 3363 consecutive patients with severe AS from the CURRENT AS Registry-2 (Contemporary Outcomes After Surgery and Medical Treatment in Patients With Severe Aortic Stenosis). Patients were classified into LG AS with normal flow (N=1005), and LG AS with low flow (N=372), and high-gradient AS (N=1986). Patients were further divided according to baseline LVEF: <50%, 50% to 59%, and ≥60%. The primary outcome measure was a composite of death or heart failure hospitalization. Within each hemodynamic subtype, clinical outcomes were compared across baseline LVEF categories of <50%, 50% to 59%, and ≥60% (reference), and unadjusted and adjusted hazard ratios (aHRs) were estimated using Cox proportional hazards models. The median follow-up period in the entire cohort was 763 days.

Results

LVEF <50% was associated with a greater hazard of death or heart failure hospitalization than LVEF ≥60% in all 3 subtypes of AS. LVEF 50% to 59% was associated with a greater hazard of death or heart failure hospitalization than LVEF ≥60% in LG AS with normal flow (aHR, 1.80 [95% CI, 1.35-2.40], P<0.001) and high-gradient AS (aHR, 1.42 [95% CI, 1.13-1.79], P=0.003) with hazards comparable to those with LVEF <50% but not in LG AS with low flow (aHR, 1.13 [95% CI, 0.72-1.79], P=0.59).

Conclusions

These findings suggest that LVEF may provide additional prognostic stratification within severe AS phenotypes, particularly in normal-flow LG AS. REGISTRATION URL: https://center6.umin.ac.jp; Unique Identifier: UMIN000034169.