Objective To investigate the prognostic impact of left ventricular (LV) diastolic dysfunction in patients with moderate aortic stenosis (AS) and preserved LV systolic function.

Methods Patients with a first diagnosis of moderate AS (aortic valve area >1.0 and ≤1.5 cm²) and preserved LV systolic function (LV ejection fraction ≥50%) were identified. LV diastolic function was evaluated using echocardiographic criteria according to the 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines. Clinical outcomes were defined as all-cause mortality and a composite of all-cause mortality and aortic valve replacement (AVR).

Results Of 1247 patients (age 74±10 years, 47% men), 535 (43%) had LV diastolic dysfunction at baseline. Patients with LV diastolic dysfunction showed significantly higher mortality rates at 1-year, 3-year and 5-year follow-up (13%, 30% and 41%, respectively) when compared with patients with normal LV diastolic function (6%, 17% and 29%, respectively) (p<0.001). On multivariable analysis, LV diastolic dysfunction was independently associated with all-cause mortality (HR 1.368; 95% CI 1.085 to 1.725; p=0.008) and the composite endpoint of all-cause mortality and AVR (HR 1.241; 95% CI 1.035 to 1.488; p=0.020).

Conclusions LV diastolic dysfunction is independently associated with all-cause mortality and the composite endpoint of all-cause mortality and AVR in patients with moderate AS and preserved LV systolic function. Assessment of LV diastolic function therefore contributes significantly to the risk stratification of patients with moderate AS. Future clinical trials are needed to investigate whether patients with moderate AS and LV diastolic dysfunction may benefit from earlier valve intervention.