Article Text
Abstract
Introduction Cardiovascular mortality is high in end-stage renal disease patients undergoing haemodialysis (HD). Early detection of cardiac dysfunction is important. Left ventricular global longitudinal strain (GLS) measures the maximal shortening of myocardial longitudinal length during systole compared to the resting length in diastole. Reduced GLS may reflect abnormal systolic function before loss of ejection fraction (EF) becomes apparent. We aimed to determine the prevalence, clinical correlates and prognostic value of abnormal GLS in stable HD patients.
Methods Clinical and echocardiographic data were obtained in a prospective study of HD patients at one centre. Survival analysis for GLS was performed using Cox regression adjusted for age, co-morbidities, dialysis chronicity, laboratory data, left ventricular mass index adjusted for height (LVMIHt2.7) and Teicholz EF.
Results 199 patients had adequate speckle tracking images; the mean age was 62 ± 14years, 69% were male, 39% had diabetes, 29% heart failure, 17% coronary artery disease. The mean GLS was -13.4 ± 3.5%, LV ejection fraction (LVEF) 63.8 ± 12.9% and LVMIHt2.7 53.6 ± 17.2g/m2.7. 98% of patients had abnormal GLS (>-20%), compared with 14% with reduced LVEF(<50%) and 55% with LV hypertrophy. Factors associated with an abnormal GLS included LVMIHt2.7 (OR 1.06, 95% CI 1.04–1.09, P < 0.01), LVEF (OR 0.96, 95% CI 0.94–0.99, P < 0.01) and diabetes (OR 2.04, 95% CI 1.08–3.9, p = 0.03). Median follow-up was 24 (17–30) months, during which there were 41 deaths (21%). After adjustment for age, diabetes, coronary artery disease, LVEF, LVMIHt 2.7, 3 month-averaged serum potassium and albumin, a less negative GLS remained an independent predictor of all-cause mortality (HR 1.18 for each 1% worsening change in GLS, 95% CI 1.03–1.35, P = 0.02). Figure 1.
Conclusions Abnormal GLS is highly prevalent amongst HD patients, and appears to be a better marker of all-cause mortality in stable HD patients than the standard echocardiographic parameters LVEF and LVMIHt2.7.
- Global longitudinal strain
- haemodialysis patients
- echocardiography