SAMUEL He PAPLNs, MJ.t; M =s J. ZB, M.D4 and JAM W. HEAys, M From the Depwtmext of Pathology, Vnderbat Uxsitzy Swool ofM n, Nesk,lce, Texc. Occasionally it is necery to evaluate the role that anmia may play in the production of hypertrophy of the heart This question may be raised when enlargement of the heart is encountered and is unaccompanied by valvular lesions or other known causes of cardiomegaly but appears m patients with anemia of significant degree. Too often, in the literature on this subject, the role of factors other thn anemia is not or cannot be evaluated, and the opinions expressed are of little worth. The contribution of severe, chronic, uncomplicated anemia to the development of cardiac hypertrophy has never been conclusively demonstrated. The occurrence of cardiomegaly in patients with severe chronic anemia has long been recognized. One of the first to note its presence was Irvine' who stated in I877 tlhat the most important change in the circulatory system in an was ". .. diatation of the ventricles of the heart, especialy, perhaps, of the left." In a report of two cases of chlorosis Hersman2 noted that enlargement of the heart was commonly observed in this disorder. With the advent of roentgenography it became possible to study variations in heart size with a higher degree of accuracy. Ball3 was the first to report a case of cardiomegaly demonstrated radiographically in a patient with uncomplicated anemia in whom there was a return of heart size to normal following correction of the anemia Since this time, a number of other authors" have shown that cardiac enlargement assocated with chronic anemia may be reduced folowing successful treatment of the anemia. The roentgenogram is highly useful in the recognition of cardiomegaly, but its effectiveness in inguisin between cardiac dilatation and hypertrophy is limited, as pointed out by Levine." Although some writers'78 have attributed the cardiac enlargement in anemia to dilatation alone, others have believed that hypertrophy is present also."