Chronic Venous Congestion Of Lung, Liver and Spleen

INTRODUCTION Congestion is a hemodynamic i.e. circulatory disorder. Definition: Congestion is a passive process resulting

from reduced outflow of blood from a tissue.

It is also called passive hyperemia .

It can be: 1)Systemic or Local And 2)Acute or chronic

Chronic is more common so it is known as Chronic Venous congestion(CVC).

TYPES OF CVC Local Systemic

Results from obstruction to venous outflow from an organ or part of the body.

Eg: Portal venous obstruction in liver cirrhosis, plasters, tumors, pregnancy and hernia.

This occurs mainly due to engorgement of systemic veins.

Eg: In right and left sided heart failure and diseases of lungs interfering pulmonary blood flow like emphysema and fibrosis.

CONSEQUENCES As a result of increased volumes and

pressures, congestion commonly leads to edema.

In passive long standing congestion, lack of blood flow causes chronic hypoxia potentially resulting in ischemic tissue injury and scarring.

Capillary rupture in chronic congestion can also cause small hemorrhagic foci, subsequent catabolism of extravasated red cells can leave residual tell tale clusters of hemosiderin laden macrophages.

GROSS APPEARANCE

Congested tissue is dusky reddish blue in color due to red cell stasis and accumulation of deoxygenated hemoglobin.

Mechanisms involved in CVC of different organs :Heart

Failure

Right-sided failure Left Sided failure

Pressure transmitted upstream of right heartPressure transmitted upstream of left heart

Systemic Venous Congestion Pulmonary congestion

CVC of lungCVC liverCVC spleenCVC kidneyCongested Leg Veins

CVC OF LUNGCAUSE: Left Heart Failure, especially in

rheumatoid mitral stenosis so that there is consequent venous pressure.

GROSS APPEARANCE: Lungs are heavy and firm in

consistency. Sectioned surface is rusty brown in

color due to which is referred to as “brown induration” of lungs.

Brown induration is due to pigmentation and fibrosis.

Brown induration Of lung seen in cut section

HISTOLOGY OF CVC LUNG Alveolar septa are widened due to

interstitial edema as well as due to dilated and congested capillaries.

Septa mildly thickened due to slight increase in fibrous connective tissue.

Minute intra-alveolar hemorrhages can be seen due to rupture of dilated and congested capillaries.

The breakdown of erythrocytes liberates hemosiderin pigment which is taken up by alveolar macrophages. The minute structures so formed are called “Heart Failure Cells”, which can be easily seen in the alveolar lamina.

CVC OF LIVERCAUSE: Occurs mainly due to right heart failure

and sometimes due to occlusion of Inferior Venacava and Hepatic Vein .

GROSS APPEARANCE: The liver is enlarged and the capsule is

tense. Cut surface shows characteristic red and

yellow mottled appearance mainly due to congested centre of lobules and fatty peripheral zone respectively.

Such an appearance of the liver is called as “Nutmeg Liver”.

Gross appearance of CVC Liver1)Nut -meg appearance 2)Peripheral fatty change

NUT-MEG LIVER

HISTOLOGY OF CVC LIVER Changes are more marked in the centrilobular

zone due to severe hypoxia than in the periphery.

Central vein as well as adjacent sinusoids are distended and filled with blood.

The centrilobular hepatocytes undergo degenerative changes , and eventually “centrilobular hemorrhagic necrosis” can be seen.

Long standing cases may show fine centrilobular fibrosis and regeneration of hepatocytes.

The peripheral zone of the lobule is less severely affected by chronic hypoxia and shows some fatty change in the hepatocytes.

CVC OF SPLEEN CAUSES: Can occur due to right heart failure and in

portal hypertension from liver cirrhosis.

GROSS APPEARANCE: Spleen in early stage is moderately

enlarged(up to 250g as compared to normal 150g.)

In long standing cases there is progressive enlargement and may weigh up to 500 to 1000g.

Organ is deeply congested, tense and cyanotic.

Sectioned surface is gray tan.

Gross appearance Of CVC spleen1)Deeply congestedwith tense capsule

2)Cut surface shows gray tan parenchyma

HISTOLOGY OF CVC SPLEEN Red pulp is enlarged due to congestion

and marked sinusoidal dilation and there are many areas of new and old hemorrhages.

Sinusoids may get converted to capillary (capillarisation of sinusoids).

There is hyperplasia of reticuloendothelial cells in the red pulp of the spleen( Splenic macrophages).

There is fibrous thickening of the capsule and the trabeculae.

Some of the hemorrhages overlying fibrous tissue get deposits of the hemosiderin pigment and the calcium salts, these organized structures are called Gamna Gandy bodies or siderofibrotic nodules.

Firmness of spleen in advanced stage is seen more commonly in hepatic cirrhosis(Congestive splenomegaly) and is the most common cause of hypersplenism.