|
|
Line 5: |
Line 5: |
| | | |
| | | |
− | ==Passive congestion== | + | ==[[Liver Congestion, Passive]] == |
− | Usually associated with right-sided heart failure because when the right side of the heart fails to function properly, blood will back up through the veins into the [[Liver - Anatomy & Physiology|liver]].
| |
| | | |
− | The appearances and changes in the [[Liver - Anatomy & Physiology|liver]] will depend on whether the conggestion is of short or long duration.
| |
− |
| |
− | ===Acute congestion===
| |
− | *occurs in acute right-sided heart failure and in shock
| |
− | ====Gross====
| |
− | *[[Liver - Anatomy & Physiology|liver]] is swollen and engorged with rounded edges to the lobes
| |
− | *fibrin may be present on the surface, coming from the dilated subcapsular lymphatics
| |
− | *blood oozes freely from the cut surface
| |
− | *the sinusoids are dilated and packed with red blood cells
| |
− | ====Microscopically====
| |
− | *hepatic venules and sinusoids engorged with blood
| |
− |
| |
− |
| |
− | ===Chronic congestion===
| |
− | *occurs in chronic right-sided heart following on from left-sided heart failure eg endocardiosis in dogs, cardiomyopathy in cats [need link in future]
| |
− | ====Gross====
| |
− | *slightly swollen with rounded edges
| |
− | *capsular surface may be paler and thicker than normal
| |
− | *alternating red and yellow areas on the cut surface: accentuates the acinar pattern
| |
− | **this contrasting red and yellow mottled gross appearance (especially that of the formalin-fixed specimen) resembles the cut surface of a nutmeg, and is referred to as ''''nutmeg'''' [[Liver - Anatomy & Physiology|liver]]
| |
− | **at this stage the [[Liver - Anatomy & Physiology|liver]] may have returned to normal size or be slightly smaller than normal
| |
− | *fibrosis can develop in the congested centrilobular zones and the liver becomes firm to section, ie cardiac fibrosis
| |
− |
| |
− | ====Microscopically====
| |
− | *the red areas are engorged and dilated hepatic venules which may show a substantial increase in perivenular fibrous tissue due to atrophy and loss of adjacent hepatocytes
| |
− | *the yellowish areas are the midzonal and perhaps periportal hepatocytes in very long standing cases which have undegone fatty change due to hypoxia and malnutrition
| |
− | *the Kuppfer cells may contain considerable haemosiderin pigment
| |
− | **golden brown in H&E sections
| |
− | **blue with Perls' Prussian blue stain (specific for haemosiderin)
| |
| | | |
| ==Thrombosis== | | ==Thrombosis== |