Nine pediatric patients underwent echocardiographic evaluation prior to and after renal transplantation. Prior to transplantation parameters of cardiac contractility such as mean velocity of circumferential fiber shortening, ejection time, ejection fraction and shortening fraction were within the normal ranges for the age group. Post transplantation there was a significant decrease in heart rate and cardiac index. In addition a dramatic increase in hemoglobin levels was observed. The improvement in circulating hemoglobin levels rather than the removal of uremia appears to be the dominant beneficial result in improving cardiovasuclar hemodynamics.