End-stage renal disease (ESRD) presents a significant health burden and is associated with high cardiovascular morbidity and mortality. This is particularly true in African Americans who generally have higher rates of cardiovascular mortality. Outcomes in ESRD are related to extent of cardiovascular disease, but markers for outcome are not clearly established. Global longitudinal strain (GLS) has emerged as an important measure of left ventricular systolic function that is additive to traditional ejection fraction (EF). It can be measured on routine digital echocardiography and is reproducible. This study tested the hypothesis that GLS is associated with mortality in black Americans with ESRD and preserved EF. Forty-eight outpatients undergoing hemodialysis, 59.4 ± 13.3 years, with EF ≥50% were prospectively enrolled. GLS, measured by an offline speckle tracking algorithm, ranged from -8.6% to -22.0% with a mean of -13.4%, substantially below normal (-16% or more negative). The prevalence of left ventricular systolic dysfunction, as determined by GLS, was 89%. Patients were followed for an average of 1.9 years; all-cause mortality was 19% (9 deaths). GLS was significantly associated with mortality (hazard ratio 1.15, 95% confidence interval 1.02 to 1.30, p = 0.02), whereas EF was not. After adjustment for multiple potential confounders (age, gender, race, smoking, hypertension, diabetes, hyperlipidemia, coronary disease, heart failure, and EF), GLS remained strongly associated with mortality (hazard ratio 1.30, 95% confidence interval 1.10 to 1.56, p = 0.002). In conclusion, GLS is an important index in patients with ESRD, which is additive to EF as a marker for mortality in this high-risk group.
All Science Journal Classification (ASJC) codes
- Cardiology and Cardiovascular Medicine