Anemia in heart failure--a concise review.

Heart failure affects 5 million persons in the United States, with 400,000 new cases occurring every year. Paradoxically, although advances in coronary angioplasty and effective drugs have increased survival post infarction, the myocardial damage and subsequent neurohormonal activation-induced remodeling causes significant morbidity years later in the form of heart failure. Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) together with beta blockers modify the neurohormonal activation associated with heart failure and are key treatments for improving cardiac function and survival. Anemia is a significant risk factor predicting morbidity and mortality in heart failure. This article describes the various etiologies of anemia in heart failure. Of particular importance is the fact that recent stem cell studies have shown that the drugs acting on the renin-angiotensin system inhibit erythropoiesis in vivo and may cause anemia in patients with both normal renal function and end-stage renal disease (ESRD). The role of angiotensin-II as an erythropoietic growth factor and ACE in facilitating erythropoiesis is described in this article. Anemia has been shown to be a modifiable risk factor and its treatment correlates with improvement in clinical outcomes. Thus, anemia, its etiology (especially the contribution of ACEIs and ARBs), physiologic and prognostic impact, and treatment in the setting of heart failure are critical areas for investigation.