Effect Of Hematocrit Levels On Cardiac Function And Structure In Hemodialysis Patients

ObjectiveCardiovascular disease is one of the most common complications and the leading causes of death in uremia patients. It is reported that the incidence of cardiovascular disease in uremia patients is around50-80%. As the great development and widely using of hemodialysis, the survival rates of uremia patients have been improved significantly. Nevertheless, the incidence of cardiovascular disease in uremia patients does not decreased consistently. Renal anemia, which could cause a series of pathophysiological changes in human organism, is the most common complication in end-stage renal disease (ESRD), especially in uremia patients with maintenance hemodialysis, thus designated as one of the most crucial factors affecting survival and prognosis in uremia patients.In recent years, recombinant human erythropoietin (rh-EPO) has been widely used in the management of renal anemia. As the elevation of hemocrit (Hct) and hemoglobulin (HGB) in uremia patients, the state of ventricular remodeling and cardiac function improves gradually, with significantly decreased incidence, hospitalization rate, and mortality of cardiovascular disease. However, there are still some debates in the clinical goal of renal anemia. In the following study, the effect of hematocrit levels on cardiac function and structure in hemodialysis patients will be investigated,providing some clues for the clinical goals enacting in renal anemia patients.Materials and MethodsAbout69hospitalized uremia patients receiving regular hemodialysis treatment at least6months between Jan2011and Jun2012at the hemodialysis center of Zaozhuang Municipal Hospital was collected in the study. The hemodialysis process of all included patients was stable, without serious acute or chronic complications. Species of dialyzer and dialysate, the flow rate of dialysate, as well as the temperature of dialysate were kept consistently in all patients. Three separate parts were included in the study.(1) Multiple correlation analysis between clinical physicochemical indexes and cardiac function in hemodialysis patients was performed.16items of physicochemical indexes and cardiac function indexes were collected, and multiple stepwise linear regression was next performed. The clinical physicochemical indexes were ranked according to size of the correlation coefficient, and the clinical indexes with the biggest correlation coefficient to cardiac function were chosen. Among these parameters, the focus will put in Hct, left ventricular ejection fraction (LVEF), left ventricular end-systolic dimension (LVESD), left ventricular end-diastolic dimension (LVEDD), interventricular septal thickness (IVST), left ventricular posterior wall thickness (LVPWT), and left ventricular mass index (LVMI).(2) The effect of hematocrit levels on cardiac function and structure in hemodialysis patients will be inspected. The69uremia patients were divided into5groups according to the levels of Hct:group A (10%≤Hct<20%), group B (20%≤Hct<25%), group C (25%≤Hct<30%), group D (30%≤Hct<33%), group E (33%≤Hct). The difference in cardiac function indexes among5groups were determined by Randomized Block Design Analysis of Variance (ANOVA), and the Hct related changing trends were also investigated.(3) The effect of different hemodialysis time on cardiac function of MHD patients. Hemodialysis patients were divided into3groups according to the duration of hemodialysis:group A (6month to2years), group B (2years to4years), group C (more than4years). Data were analyzed by randomized blocks analysis of variance.Results:(1) Hct is positively correlated with LVEF, while it shows no correlation with LVESD and LVMI.(2) As the Hct rises, levels of LVEF grow up accordingly;(3) LVESD has the trend of down then up and then down with the increase of Hct, and statistical significance was found between group B and group C (P=0.048);(4) As the gradually prolonging of hemodialysis time, especially between2and4years, the LVEF showed a significant drop, and there was significant difference between group A and group B (P=0.046)ConclusionsThe higher levels of Hct (≥33%) and long-term maintenance can significantly improve the left ventricular systolic function and reduce the chances of heart failure in hemodialysis patients. It also has the trend to reverse the left ventricular hypertrophy.