Passive hepatic congestion

Passive hepatic congestion, also known as congested liver in cardiac disease, describes the stasis of blood in the hepatic parenchyma, due to impaired hepatic venous drainage, which leads to the dilation of central hepatic veins and hepatomegaly. 

Passive hepatic congestion is a well-studied result of acute or chronic right-sided heart failure.

Clinical presentation

Clinical findings in these patients are dominated by those of right-sided heart failure. Mild right upper quadrant abdominal pain has been reported to be the result of hepatomegaly and stretching of the hepatic Glisson capsule ¹. Asymptomatic elevation of serum liver enzymes may also occur ⁴. 

Pathology

Elevated hepatic venous pressure and a decrease in hepatic venous flow cause hypoxia in hepatic parenchyma, and eventual diffuse hepatocyte death and fibrosis. This results in a micronodular cirrhosis, which is indistinguishable from cirrhosis produced by other causes ².

Etiology

All forms of heart disease (congenital or acquired) are linked to passive hepatic congestion. 

Most common causes of passive hepatic congestion ⁴:

• congestive heart failure
• restrictive cardiomyopathy or constrictive pericarditis
• right-sided valvular disease involving the tricuspid or pulmonary valve
• pulmonary-related right heart failure 

Radiographic features

Ultrasound

Early in the course of the disease, the main abnormality is enlargement of the right hepatic lobe. Normally the right hepatic vein measures <6 mm and, in these patients, its mean is ~9 mm ^{ref needed}. 

• real-time B-Mode:
  • dilated IVC/hepatic veins, hepatomegaly, ± ascites 
  • diameter of hepatic vein 
    • normal: 5.6 to 6.2 mm
    • mean diameter: 8.8 mm (in passive congestion) 
    • increases up to 13 mm with pericardial effusion
• color Doppler:
  • spectral velocity pattern (lVC & hepatic veins)
    • loss of normal triphasic flow pattern
    • spectral signal may have an "M" shape
    • flattening of Doppler waveform in hepatic veins
    • to-and-fro motion in hepatic veins and IVC
• spectral velocity pattern (portal vein)
  • increased pulsatility of the portal venous Doppler signal

CT

• early enhancement of dilated IVC and hepatic veins due to contrast reflux from the right atrium into IVC
• heterogeneous, mottled and reticulated mosaic parenchymal pattern with areas of poor enhancement
• peripheral large patchy areas of poor/delayed enhancement
• periportal low attenuation (perivascular lymphedema) 
• ascites
• hepatomegaly

Chest images may show cardiomegaly and pericardial and pleural effusion ⁴. 

MRI

Macroscopically CT and MRI are able to depict cirrhotic changes as non-specific findings.

• T1 C+ (Gd)
  • liver enhancement pattern: reticulated mosaic pattern of low signal intensity linear markings which become more homogenous in 1-2 minutes.
  • hepatic veins and suprahepatic IVC: early enhancement due to reflux from the atrium 
  • portal vein: diminished, delayed or absent enhancement
• fast low-angle shot (FLASH) contrast-enhanced MRI: early reflux of contrast into dilated hepatic veins and IVC
• T2: periportal high signal intensity (periportal edema) 
• MR angiography: slow or absent antegrade flow within IVC

Differential diagnosis

General imaging differential considerations include:

• Budd Chiari syndrome
• acute viral hepatitis
• hepatic veno-occlusive disease

See also

• congestive hepatopathy