CHAP. III.] THE BLOOD IN DISEASE. 165 



of biliary ingredients into the blood ; congested kidneys will secrete a 

 urine more or less charged with albumin and probably deficient in 

 urea, and secondarily there may be set up the condition of uraemia. 



So multifarious are the ways in which heart disease may modify 

 the condition of the blood, that it would be useless to attempt to 

 classify all the changes which are thus brought about. 



TheAnae- Amongst the most interesting of the phenomena 



mia of Heart induced by heart disease is the condition of anaemia, 

 disease. Cases of anaemia in connection with heart disease may 



be arranged in two classes. In the first, the anaemia follows very 

 closely upon the establishment of the cardiac lesion, and is obviously 

 dependent upon the disturbance in the blood-pressure, which has 

 not yet been compensated for, as it subsequently is, by changes in 

 the circulatory apparatus. The establishment of anaemia in these 

 cases is clearly explained. A certain difference between the arterial 

 and venous pressure, and more than that, a certain value of the 

 arterial pressure, is absolutely necessary in order that the nutrition of 

 each organ of the body shall be efficiently maintained; when the 

 conditions for effecting this do not exist, an alteration of the blood 

 will be amongst the first evidences of impaired nutrition. 



Thus, then, we explain the anaemia which occurs so often a few 

 months after the setting up of an organic lesion of the heart by the 

 endocarditis of rheumatism. In this class of cases, however, the dis- 

 order of nutrition is often only transitory, as the disturbances in the, 

 circulation which followed the sudden establishment of the cardiac, 

 lesion are compensated, more or less completely and more or less 

 durably, by changes brought about, somewhat gradually, in the 

 circulatory apparatus. The compensating hypertrophy of the left 

 ventricle in aortic regurgitation, and of the left auricle in mitral 

 stenosis, are the best illustrations of the changes referred to. 



In a second class of cases, however, anaemia occurs, and is more 

 intense than in those already referred to ; these are cases in which 

 anaemia occurs in the last stages of heart disease. After existing 

 for many years in an apparently dormant condition, without in- 

 fluencing in any very obvious manner the health of the individual 

 subject to them, certain heart affections reveal themselves apparently 

 with great suddenness. The shortness of breath, the puffy swelling 

 of the feet, which had been scarcely noticed for a long time, are 

 followed by symptoms which indicate how profoundly the circulation 

 is interfered with. We have no longer evidences of a mere deficient 

 blood-supply to important organs, depressing their functional activity, 

 but the sure signs of a disturbance of the proper relations between 

 arterial and venous pressure, which no compensating changes can 

 overcome. Congestions of important organs occur, dropsical accumu- 

 lations in the serous sacs or the areolar tissue and, of necessity, if the 

 patient live long enough, anaemia. 



This anaemia is not difficult to explain. It is dependent partly 

 upon the alimentary canal being unfit to digest enough food to make 



