Global Longitudinal Strain is an Independent Predictor of Cardiovascular Events in Patients with Maintenance Hemodialysis: a Prospective Study Using Three-dimensional Speckle Tracking Echocardiography

The aim of this study was to investigate subclinical LV changes in patients with maintenance hemodialysis (MHD) using three-dimensional speckle-tracking echocardiography (3DSTE) and to explore its prognostic value. A total of 88 individuals were consecutively enrolled, including 66 subjects with MHD and 22 age- and sex-matched controls. Conventional and Real-time three-dimensional echocardiography was performed and analyzed. Left ventricular volume, strain and time parameters were calculated and compared. The MHD cohort was then followed to record cardiovascular events (CVE). Univariate and multivariate logistic regression analysis was used to identify independent predictors of CVE. Compared with the controls, MHD patients had significantly lower global longitudinal and radial strain (GLS and GRS), and LVEF (GLS: -17.0 ± 2.3 vs -18.8 ± 2.3 %; GRS: 37.0 ± 3.5 vs 39.4 ± 3.4 %; LVEF: 57.3 ± 4.2 vs 59.5 ± 3.5 %, p < 0.05 for all), as well as enlarged LV volume (EDV: 51.3 ± 14.2 vs 40.4 ± 7.3 ml/m(2); ESV: 22.0 ± 6.9 vs 16.3 ± 3.2 ml/m(2); SV: 29.2 ± 8.0 vs 24.0 ± 4.7 ml/m(2), p < 0.01 for all) and LV mass index (LVMi) (107.7 ± 28.6 vs 83.7 ± 20.6 g/m(2)). Time to minimum end-systolic volume and to peak longitudinal strain (T-msv and T-ls) were delayed in the MHD group (T-msv: 38.1 ± 5.2 vs 41.4 ± 6.4 %; T-ls: 38.1 ± 4.6 vs 42.1 ± 6.8 %, p < 0.05). Systolic dyssynchrony index (SDI) of the MHD group was significant larger than that of the controls (6.4 ± 1.5 vs 4.9 ± 1.8 %, p < 0.01). CVE occurred in 23 patients within a follow-up of 2 years. GLS and LVMi remained significant predictors of CVE [OR = 3.94, 95 % CI (1.33-11.66) for GLS and OR = 1.04, 95 % CI (1.01-1.07) for LVMi, p = 0.013 and 0.009, respectively]. Subclinical LV deformation and dysfunction exist in MHD patients with preserved LVEF. GLS and LVMi are two important predictors of CVE in MHD patients. Strain assessment in MHD patients may contribute to better vascular risk stratification.