The effects of anemia on the circulatory system can be profound. Because the viscosity of blood depends almost entirely on the concentration of RBCs,
the resulting hemodilution of severe anemia decreases peripheral resistance,
causing greater quantities of blood to return to the heart.
the in creased circulation and turbulence within the heart may produce a murmur.
Because the cardiac workload is greatly in creased,
especially during exercise, infection, or emotional stress, cardiac failure may ensue.