Blood volume measurements in patients with heart failure and a preserved ejection fraction: implications for diagnosing anemia.

Racial differences in the prevalence of anemia in patients with heart failure have been noted. The diagnosis of anemia in heart failure patients can be confounded by many factors. Plasma volume expansion is one of the most prominent confounders. The authors investigated the difference of anemia prevalence using two different diagnostic techniques: peripheral hemoglobin recommended by the World Health Organization criteria and blood volume (BV) analysis. Racial disparities in the prevalence of anemia using both measures were compared. Sixty patients with heart failure and preserved ejection fraction (HFPEF) underwent measurement of BV by a radio-labeled albumin technique. Anemia was defined by both WHO criteria and by measured red blood cell volume (RBCV) >10% below ideal. Anemia was found in 67% of patients by the peripheral hemoglobin technique with no racial disparity. Only 35% of the patients had anemia by the BV analysis, with a 2-fold higher prevalence among Hispanics compared with whites and blacks. In patients with HFPEF, the diagnosis of anemia based on hemoglobin is confounded by plasma volume derangements resulting in significant overdiagnosis in this cohort. Racial differences in the rate of anemia were found. Such data could have important implications for the diagnosis and management of anemia in ethnic minorities with HFPEF.