Abstract
Background:To assess whether global longitudinal strain (GLS) can discriminate high-risk patients with adverse outcome in paradoxical low-flow, low-gradient (LFLPG) severe aortic stenosis (AS).Methods and Results:We enrolled 204 patients with severe AS (indexed aortic valve area [iAVA] <0.6 cm2/m2) and preserved left ventricular ejection fraction (LVEF >50%). Patients were divided into 4 groups according to flow state (stroke volume index < or > 35 ml/m2) and mean pressure gradient (< or > 40 mmHg). LV GLS was measured by 2-dimensional speckle-tracking analysis. The primary endpoint consisted of major cardiovascular events, including aortic valve replacement. During a mean 399-day follow-up, 51 (25%) patients met the primary endpoint. Among the 98 LFLPG AS patients, GLS was significantly reduced in patients with any event (−15.6±4.5% vs. −19.4±3.6%, P=0.002). Using receiver-operating characteristic analysis, we classified LFLPG AS patients as impaired GLS (GLS ≥−17%, n=24) or preserved GLS (GLS <−17%, n=74). The impaired GLS group had smaller iAVA, higher LV mass index, higher E/E’, and lower overall 2-year event-free survival (57% vs. 97%; P<0.001) than the preserved GLS group.Conclusions:Longitudinal function was severely impaired in patients with LFLPG AS and they had poor prognosis. GLS could stratify the high-risk group for future adverse outcomes. Patients with paradoxical LFLPG AS comprised a mixed group with different LV mechanical properties associated with different prognoses. (Circ J 2014; 78: 2750–2759)
