P6475Global longitudinal strain as a prognostic marker in patients with normal left ventricular ejection fraction: a systematic review and meta-analysis

Abstract

Background: Evidence suggests that global longitudinal strain (GLS) measured by speckle tracking echocardiography in patients with heart failure predicts risk of mortality and adverse cardiovascular outcomes. However, the prognostic signif-icance of abnormal GLS in subjects with normal left ventricular ejection fraction (LVEF) without clinical heart failure remains unclear. Purpose: To assess the association between abnormal GLS and clinical outcomes in subjects with normal LVEF. Methods: EMBASE, MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL) and trial registries were searched systematically for studies inves-tigating an association between GLS and clinical events in patients with normal LVEF (>50%). The primary outcome was the composite of major adverse cardiovascular outcomes (MACE) (including all-cause mortality, cardiovascular mortality, vascular death, myocardial infarction, new heart failure, heart failure hospitalisation, target vessel revascularisation and/or ischemic stroke as defined by individual studies) or all-cause mortality. Two independent reviewers followed PRISMA protocol to extract the data and the review protocol was published in PROSPERO register (CRD42018086519). Results: Nine studies involving 2767 patients (mean age 67±1 years, 54% male and BMI 28±5 kg/m$sup$2$/sup$) were included in the final quantitative analysis. Prevalence of cardiovascular risk factors were: hypertension (57%); diabetes (28%); smoking (25%); hypercholesterolemia (34%); and past history of coronary artery disease (30%). Thirty percent of the population used angiotensin-converting-enzyme in-hibitors or angiotensin-II-receptor blockers and 29% were on beta-blockers. Mean pooled cut-off across the studies for abnormal GLS was-16%. During median follow up of 3.4±2.8 years, abnormal GLS was associated with MACE (HR 1.22, 95% confidence interval (CI) 1.12-1.33, I$sup$2$/sup$ 61.2%) (Figure 1) and all-cause mortality (HR 1.33, 95% CI 1.07-1.66, I$sup$2$/sup$ 78.3%). [Table Presented] Conclusion: In patients with normal LVEF, abnormal GLS predicts the risk of all-cause mortality and MACE. Since strain imaging is an accessible and practical technique it may be useful in assessing early left ventricular systolic dysfunction in the context of normal LVEF. Further prospective controlled studies of GLS in predicting adverse outcomes among homogeneous population are required.