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

Hindawi Disease Markers Volume 2019, Article ID 7512805, 12 pages https://doi.org/10.1155/2019/7512805 Research Article 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 Jiun-Chi Huang ,1,2,3,4 Ho-Ming Su,3,4,5 Pei-Yu Wu ,1,2,3 Jia-Jung Lee,2,4 Wen-Hsien Lee,1,3,4,5 Szu-Chia Chen ,1,2,3,4 Yi-Wen Chiu,2,6 Ya-Ling Hsu,1,7 Jer-Ming Chang ,2,6,8 and Hung-Chun Chen2,6 1 Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan 3 Department of Internal Medicine, Kaohsiung Municipal Hsiao-Kang Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan 4 Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan 5 Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan 6 Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan 7 Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan 8 Department of Internal Medicine, Kaohsiung Municipal Cijin Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan 2 Correspondence should be addressed to Szu-Chia Chen; Received 27 March 2019; Revised 18 July 2019; Accepted 30 July 2019; Published 5 September 2019 Guest Editor: Christos Chadjichristos Copyright © 2019 Jiun-Chi Huang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 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. 2 1. Introduction Cardiovascular (CV) disease is the leading cause of mortality in patients undergoing hemodialysis (HD) [1]. Higher prevalence of traditional risk factors and functional abnormalities of the heart may contribute to this high CV risk in end-stage renal disease (ESRD) [2, 3]. Pressure and volume overload could cause such cardiac abnormalities [4, 5]. Two-dimensional (2D) speckle tracking echocardiography (STE) allows for angle-independent quantification of myocardial deformation to more accurately reflect systolic and diastolic performances of all myocardial segments [6, 7]. 2D STE can assess the left ventricular (LV) early global diastolic strain rate (E’sr). Furthermore, the early mitral inflow velocity (E) to E’sr ratio has been reported to be an emerging index of LV diastolic function [8, 9] and is strongly correlated with invasively measured LV filling pressure [10– 12]. The E/E’sr ratio is associated with unfavorable outcomes among patients with acute myocardial infarction [13] and systolic heart failure [14]. Global LV longitudinal systolic strain (GLS) has been recognized as a proper indicator of LV systolic function [7, 15]. Less negative GLS is associated with an increased risk of death in patients undergoing dialysis [16, 17]. However, the associations between the E/E’sr ratio and the risk of mortality and CV outcomes have never been investigated in chronic HD patients. Therefore, this study is aimed at examining the prognostic significance of the E/E’sr ratio and GLS in the prediction of overall mortality, CV mortality, and major adverse cardiovascular events (MACE) in maintenance HD patients. We further explored whether the emerging indices of LV diastolic and systolic functions outperformed the conventional echocardiographic parameters in the prediction of mortality and CV outcomes. 2. Materials and Methods 2.1. Study Patients. The inclusion criterion of the present study was patients with maintenance hemodialysis HD > 3 months at the outpatient HD unit. This study enrolled 219 maintenance HD patients at a regional hospital in Taiwan from March to October 2014. Patients with refusal of examinations (n = 18), lack of STE measurements (n = 7), and atrial fibrillation (n = 4) were excluded. No patient was excluded because of poor echogenicity. Overall, 190 study patients were included (Figure 1). The study adhered to the Declaration of Helsinki and was approved by the Institutional Review Board of Kaohsiung Medical University Hospital, and all participants provided their written informed consent. 2.2. Echocardiographic Measurements. Patients received echocardiographic measurements in the left decubitus position by one well-experienced cardiologist, using a Vivid 7 system (GE Vingmed Ultrasound AS, Horten, Norway). The cardiologist was blind to patients’ clinical information. Early diastolic velocities (E’) of lateral and septal (...truncated)