Effect of Erythropoietin Therapy on Cardiac Structural and Functional Changes in End Stage Renal Disease: A Comparative Study of Full versus Partial Anemia Correction
Background: Anemia contributes to the development and progression of the structural and functional abnormalities of the heart in patients with end stage renal disease (ESRD). However, the optimal level of hemoglobin correction and its effect on cardiac structure and function is not well defined. This study aimed to assess the cardiac benefits of correction of anemia and to compare the effect of full versus partial anemia correction in hemodialysis patients without symptomatic heart disease.
Patients and Methods: The study was conducted on 45 patients with ESRD divided into three groups; GI: 15 patients treated to reach a target hemoglobin level from 13 to 14 gm/dL, GII: 15 patients treated to reach a target hemoglobin level from 11 to 12 gm/dL and GIII: 15 patients without anemia correction as controls. High and lower hemoglobin targets were generated with erythropoietin (EPO) and iron therapy over 24 weeks and maintained for an additional 24 weeks.
Results: Correction of anemia caused significant reduction in left ventricular end diastolic dimension (LVEDD), left ventricular end systolic dimension (LVESD), left ventricular end diastolic volume (LVEDV), left ventricular end diastolic volume index (LVEDVI), interventricular septal thickness (IVSd), left ventricular mass (LVM), left ventricular mass index (LVMI), E wave deceleration time (E-DT), isovolumetric relaxation time (IVRT) and Tei index and significant increase in ejection fraction (EF%) and fractional shortening (FS%) in both groups with high and low hemoglobin targets. There were no significant differences in the percentage changes in these parameters between patients with high and low hemoglobin targets. Patients who were maintained without correction of anemia showed significant increase in LVEDD, LVESD, LVEDV, LVEDVI, LVM, LVMI, E-DT, IVRT and Tei index.
Conclusions: Early correction of anemia with EPO in patients with ESRD results in regression of left ventricular hypertrophy and improvement of left ventricular function. However, full correction of anemia does not have additional benefit on cardiac structure or function compared with partial correction. It is recommended to use the low target hemoglobin level rather than the higher level to correct anemia in patients with ESRD, because of increased risk, a likely increased cost and no additional ardiovascular benefit from full anemia correction.
Key words: Cardiac function, cardiac structure, anemia correction, erythropoietin therapy, end stage renal disease.