In the preceding article I showed how I succeded in producing chronic congestive heart failure in rabbits with aortic or pulmonic stenosis, and concluded that cardiac hypertrophy occurred at the chamber which is under the strain retrograde from the site of stenosis.In this study a series of seventy rabbits with aortic or pulmonic stenosis, four of which showed chronic congestive heart failure, were studied to present the percentage of roentgen-ray areas of the heart from the normal at different times, observations for terminal weight of various organs, the ratio of organ weight to body weight, and the width of the fibers of the left and the right ventricles. The summary and conclusion of this study is as follows : 1. As to the average changes of roentgen-ray areas of the heart from the normal at different times, the initial enlargement appeared and reached its maximum in 3.5±2.7 days following the operation of stenosis and the change in percentage of the normal was 139±22.6%. Following this initial enlargement, it decreased in size to 107±11.4% in 24±17.3 days after the operation. The second enlargement followed this period and continued until death occurred. In the hundredth day the average change was 127±21.8%. Each time when sensitized, the size of the heart changed in the way similar to that observed just after the operation of stenosis.2. Cardiac hypertrophy occurred within 3.5±2.7 days following the operation of stenosis when the heart showed dilatation, and it became conspicuous gradually.3. In normal rabbits the width of the fibers of the left ventricle laid between 13 and 14 microns, and that of the right, between 11 and 13 microns These fibers increased in width with cardiac hypertrophy. In the four hundredth day after the operation the average width of the fibers of the left ventricle was 16.0 microns and that of the right, 13.5 microns in aortic stenosis, and 15.7 microns and 16.3 microns respectively in pulmonic stenosis.4. Although various organs of the rabbits with aortic or pulmonic stenosis (twelve had been further sensitized after the operation to produce allergic myocarditis) revealed venous congestion, the congestion of the lungs or the liver was most striking, and those of the spleen and the kidneys were rather slight. These results indicate that the passive venous congestion is localized in the organs retrograde from the failing cardiac chamber ; that it is more striking in those organs proximal to that chamber;and that this congestion is already present even in the so-called "Stage of Incompensation, " when the distal venous congestion (like ascites, hydrothorax, subcutaneous edema, and so on, which are well-recognized as the signs of decompensation clinically and at autopsy) does not yet appear.

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