Ratio of Early Mitral Inflow Velocity to the Global Diastolic Strain Rate and Global Left Ventricular Longitudinal Systolic Strain Predict Overall Mortality and Major Adverse Cardiovascular Events in Hemodialysis Patients

Abstract

Background. The ratio of early mitral inflow velocity to the global diastolic strain rate (E/E’sr) and global longitudinal systolic strain (GLS) of the left ventricle (LV) are emerging indices of diastolic and systolic functions, respectively, for the LV. Their prognostic significance in the prediction of mortality and cardiovascular (CV) outcomes remains underexplored in hemodialysis (HD) patients. Methods. This prospective study included 190 maintenance HD patients. The E/E’sr ratio and GLS were assessed using two-dimensional speckle tracking echocardiography. The clinical outcomes included overall mortality, CV mortality, and major adverse cardiovascular events (MACE). The associations between the E/E’sr ratio, GLS, and clinical outcomes were evaluated using multivariate Cox regression analysis. The incremental values of the E/E’sr ratio and GLS in outcome prediction were assessed by χ2 changes in Cox models. Results. Over a median follow-up period of 3.7 years, there were 35 overall deaths, 16 CV deaths, and 45 MACE. Impaired diastolic function with a higher E/E’sr ratio was associated with overall mortality (HR, 1.484; 95% CI, 1.201−1.834; p<0.001), CV mortality (HR, 1.584; 95% CI, 1.058–2.371; p=0.025), and MACE (HR, 1.205; 95% CI, 1.040−1.397; p=0.013) in multivariate adjusted Cox analysis. Worsening GLS was associated with overall mortality (HR, 1.276; 95% CI, 1.101−1.480; p=0.001), CV mortality (HR, 1.513; 95% CI, 1.088−2.104; p=0.014), and MACE (HR, 1.214; 95% CI, 1.103−1.337; p<0.001). The E/E’sr ratio and GLS had better outcome prediction than the E to early diastolic mitral annular velocity (E/E’) ratio and left ventricular ejection fraction (LVEF). Moreover, adding the E/E’sr ratio and GLS to Cox models containing relevant clinical and conventional echocardiographic parameters improved the prediction of overall mortality (p<0.001), CV mortality (p<0.001), and MACE (p<0.001). Conclusion. The E/E’sr ratio and GLS, as emerging indices of LV diastolic and systolic functions, significantly predict mortality and CV outcomes and outperform conventional echocardiographic parameters in outcome prediction in HD patients.