Association of Left Ventricular Longitudinal Strain with Mortality among Stable Hemodialysis Patients with Preserved Left Ventricular Ejection Fraction

BACKGROUND AND OBJECTIVES: Little is known about the optimal echocardiographic parameters for risk stratification in stable dialysis patients with preserved left ventricular ejection fraction (LVEF) (ejection fraction ≥ 50%). Left ventricular (LV) global peak systolic longitudinal strain (GLS) is the ratio of the maximal change in myocardial longitudinal length in systole to the original length and reliably and accurately assesses LV function. During systole, LV myocardium in the longitudinal direction shortens and GLS is represented by a negative value. The more negative value of GLS, the better the LV function is. This study hypothesized that subtle abnormalities of GLS are associated with an adverse prognosis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This prospective study collected clinical and echocardiographic data (including GLS) from 88 stable hemodialysis patients (mean age 67.0 ± 11.2 years; 35% men) with preserved LVEF. These patients were enrolled from December 2008 to January 2009 and were followed-up for 25.6 ± 9.9 months. The primary outcome was all-cause mortality. Multivariate Cox regression analysis was used to investigate risk factors for mortality. RESULTS: The mortality group (n=24) had lower albumin levels, less negative GLS, and higher prevalence of coronary artery disease and diabetes mellitus than the survival group. Using a GLS cutoff value of -15%, the less negative GLS group (GLS ≥-15%) had a higher mortality rate. Cox regression analyses revealed that lower albumin level (hazard ratio, 0.16; 95% confidence interval, 0.05 to 0.53; P=0.003) and less negative GLS (hazard ratio, 3.57; 95% confidence interval, 1.41 to 9.04; P=0.01) were independent predictors of all-cause mortality. Furthermore, less negative GLS was associated with a higher cardiovascular death rate. CONCLUSIONS: Less negative GLS is predictive of poor prognosis among stable hemodialysis patients with preserved LVEF.