The results of anemia correction by recombinant human erythropoietin (rHuEPO) therapy with regard to cardiac function and left ventricular hypertrophy in dialysis patients are controversially discussed. The aim of the study was to assess the effects of therapy rHuEPO on cardiac morphology and function in dialysis patients. We studied 11 clinically stable hemodialysis patients with severe renal anemia (hematocrit <27%) and increased left ventricular mass index (LVMi) with no history of coronary or valvular heart disease, systemic disease, severe hyperparathyroidism, hypertension stage 2 or higher, transfusion-dependent anemia, and concurrent rHuEPO treatment. The patients were treated with rHuEPO administered subcutaneously once or twice weekly at a mean dose of 80 ± 31 IU/kg week until the hematocrit was >30% and underwent a complete Doppler echocardiographic study at baseline and at follow-up (after 12.2 ± 2.9 months). At follow-up, ejection fraction and fractional shortening significantly increased from 62.7 ± 13.8 to 67.8 ± 9.7% (p < 0.05) and from 35.5 ± 9.8 to 39.4 ± 7.1% (p < 0.05), respectively, whereas mean velocity of circumferential fiber shortening demonstrated a trend towards amelioration from 1.18 ± 0.23 to 1.27 ± 0.27 circ/s (n.s.). LVMi and morphological data remained unchanged throughout the study. Nevertheless, LVMi changes showed two different behaviors with respect to baseline values: in 6 patients with higher baseline values, LVMi decreased from 229 ± 36 to 191 ± 45 g/m<sup>2</sup> (p < 0.05), while it worsened in 5 patients with less marked LVMi, increasing from 141 ± 32 to 186 ± 40 g/m<sup>2</sup> (p < 0.05). Our data demonstrate that partial correction of renal anemia with rHuEPO therapy seems to improve cardiac performance and to induce a regression of left ventricular hypertrophy, particularly in patients with greater baseline hypertrophy, ultimately confirming the multifactorial pathogenesis of left ventricular hypertrophy.