A global longitudinal strain cut‐off value to predict adverse outcomes in individuals with a normal ejection fraction

AIMS: Global longitudinal strain (GLS) has become an alternative to left ventricular ejection fraction (LVEF) to determine systolic function of the heart. The absence of cut‐off values is one of the limitations preventing full clinical implementation. The aim of this study is to determine a cut‐off value of GLS for an increased risk of adverse events in individuals with a normal LVEF. METHODS AND RESULTS: Echocardiographic images of 502 subjects (52% female, mean age 48 ± 15) with an LVEF ≥ 55% were analysed using speckle tracking‐based GLS. The primary endpoint was cardiovascular death or cardiac hospitalization. The analysis of Cox models with splines was performed to visualize the effect of GLS on outcome. A cut‐off value was suggested by determining the optimal specificity and sensitivity. The median GLS was −22.2% (inter‐quartile range −20.0 to −24.9%). In total, 35 subjects (7%) had a cardiac hospitalization and/or died because of cardiovascular disease during a follow‐up of 40 (5–80) months. There was a linear correlation between the risk for adverse events and GLS value. Subjects with a normal LVEF and a GLS between −22.9% and −20.9% had a mildly increased risk (hazard ratio 1.01–2.0) for cardiac hospitalization or cardiovascular mortality, and the risk was doubled for subjects with a GLS of −20.9% and higher. The optimal specificity and sensitivity were determined at a GLS value of −20.0% (hazard ratio 2.49; 95% confidence interval: 1.71–3.61). CONCLUSIONS: There is a strong correlation between cardiac adverse events and GLS values in subjects with a normal LVEF. In our single‐centre study, −20.0% was determined as a cut‐off value to identify subjects at risk. A next step should be to integrate GLS values in a multi‐parametric model.