HYPEILEMIA OF THE LIVER. 659 



explained, on the complete or incomplete occurrence and on the longer 

 or shorter duration of compensatory hypertrophy of the heart. 



2. We may readily understand the congestions accompanying all 

 organic diseases of the heart and pericardium, which induce obstruction 

 to the escape of blood from the veins. 



3. Under the same class would come congestions, occurring with 

 enfeebled action of the heart, without perceptible organic change of 

 that organ, either when appearing late in the course of exhausting 

 acute diseases or in chronic marasmus. The effect on the distribution 

 of the blood is the same in commencing paralysis of the heart as in 

 degeneration of its substance. 



4. Congestion of the liver is often induced by acute and chronic 

 diseases of the lung, by which the pulmonary capillaries are atrophied 

 or compressed, and the right side of the heart and vena cava overfilled, 

 as in emphysema, cirrhosis, compression from pleuritic effusions, etc. 



5. Lastly, in some few cases, compression of the vena cava by tu- 

 mors, particularly aneurisms of the aorta, has been observed as the 

 cause of congestion of the liver. 



ANATOMICAL APPEARANCES. According to the degree of the hy- 

 persemia, the liver is more or less swollen ; sometimes it is very much 

 so ; its shape is unchanged, except that it is more increased in thick- 

 ness than in length. When the swelling is decided, the peritoneal 

 coating is smooth, glistening and tense, the resistance of the liver is 

 increased. When cut, quantities of blood flow over the cut surfaces. 

 The latter either appear evenly dark or are spotted ; this is particularly 

 apt to occur when there has been congestion for a long time ; dark 

 spots, corresponding to the dilated venae centrales, the commencement 

 of the hepatic veins, and varying in shape with the direction of the 

 cut, alternate with brighter-colored ones which do not contain so much 

 blood, and which represent the termination of the portal vessels. The 

 spotted appearance, which has given rise to the much misused name 

 of nutmeg liver, becomes still more marked, when the more bloodless 

 spots in the vicinity of the dilated central veins appear decidedly yel- 

 low from obstruction of the bile-ducts. The latter may be partly due 

 to catarrh of the gall-ducts, induced by the hyperaemia of their mucous 

 membrane ; partly to the pressure of the enlarged vessels obstructing 

 the free escape of bile from the small bile-ducts ; and it may be partly 

 due to gastroduodenal catarrh, induced by the same causes that excite 

 the hyperaemia of the liver. 



The enlarged liver may subsequently become smaller, and acquire 

 a granular appearance, so that, on superficial examination, it may 

 be confounded with granular liver. This is usually termed the atro- 

 phied form of nutmeg-liver. According to Frerichs* the atrophy 



