Heart Weights of Normal and Anemic Animals

Abstract

Cardiac hypertrophy resulting from nutritional anemia reported by Forman and Daniels 1 was based on moist heart weights. There was nothing to indicate whether the enlargement was a true hypertrophy—an increase in muscle fiber, or was caused by an imbibition of water. In the present study both moist and dry heart weights of anemic rats at different hemoglobin levels, were compared on the basis of sex, age, body weight, and body length with those of normal animals of the same sex, age, length, and weight. In an attempt to determine the fate of these hypertrophied hearts, other anemic animals were fed anemia correcting diets. When the haemoglobin and red cell count were again within the normal range, their hearts were compared with those of normal individuals.

The findings indicate that nutritional anemia produces a true cardiac hypertrophy, the result of increased muscle fiber. The dried heart weights were found to be distinctly heavier, whether compared on the basis of age, weight, or length, the degree of enlargement based on the dry heart weights being inversely proportional to the degree of anemia. The ratio of dried heart weight to body length was found to average approximately the same for male and female in both normal and anemic groups, although a consistently higher ratio was observed amongst the latter. During the period of observation (24 to 44 days), the animals receiving the anemia correcting diet continued to show a high degree of hypertrophy in spite of the fact that the blood haemoglobin and red cell count had returned to normal.