Tissue Doppler imaging predicts outcomes in hemodialysis patients with preserved left ventricular function

BACKGROUND: Cardiovascular disease is a major cause of mortality in patients with end-stage renal disease (ESRD). In addition to arteriosclerosis (arterial stiffness) and atherosclerosis, left ventricular (LV) hypertrophy and LV systolic dysfunction are the major cardiac determinants of cardiovascular mortality in hemodialysis patients. Although LV diastolic dysfunction is common in patients with ESRD, its prognostic value is yet to be established. METHODS: A total of 103 ESRD patients (52 females, 51 males, age 51 ± 14 years) receiving regular hemodialysis and with preserved LV systolic function were prospectively enrolled in the current study. A comprehensive cardiovascular evaluation was performed at baseline. LV diastolic function was assessed using Doppler mitral inflow velocity and tissue Doppler imaging (TDI) of the mitral annulus velocity. Predictors for hospitalization and all-cause mortality were identified via Cox proportional hazards analysis. RESULTS: There were 20 deaths and 46 hospitalizations during a follow-up period of 67.9 ± 20.2 months. After adjusting for age, aortic pulse wave velocity (PWV), and carotid intima media thickness, Cox analysis demonstrated that ratio of early ventricular filling velocity (E) to early diastolic tissue velocity mitral annulus (E') (E/E') was a significant predictor for hospitalization (hazard ratio [HR] 1.235 and 95% CI 1.115-1.368 per-1SD). E' also independently predicted mortality (HR 0.682, 95% CI 0.472-0.985). The TDI parameters significantly correlated with the LV mass index and PWV. CONCLUSION: The findings of the current study suggest that diastolic function, as indexed by TDI, is an independent predictor of hospitalization and mortality in ESRD patients receiving regular hemodialysis and with preserved LV systolic function. The TDI parameters may reflect the impairment of arterial function and LV pressure overload.