Radiology of Heart Failure

Question 1

What are the stages of heart failure seen on a chest X ray?

Answer 1

1. Redistribution
2. Interstitial oedema
3. Alveolar thickening

Question 2

What are the values of Pulmonary Wedge Pressures for the 3 stages of heart failure?

Answer 2

1. Redistribution stage : 13 - 18 mmHg
2. Interstitial oedema stage : 18 - 25 mmHg
3. Alveolar oedema stage : more than 25 mmHg

Question 3

What are the radiological signs of Redistribution stage of heart failure?

Answer 3

1. Upper lobe vasculature thickening

2. Cardiomegaly

Question 4

What are the radiological signs of Interstitial Oedema stage?

Answer 4

1. Kerley Lines
2. Perihilar haziness (blood vessels have ill-defined margins)
3. Peribronchial thickening

Question 5

What are Kerley lines?

Answer 5

Thickening of interlobular septae due to fluid accumulation or fibrosis.

Question 6

Types of Kerley Lines?

Answer 6

Kerley A - oblique lines longer than Kerley B lines, distention of of anastomoses of peripheral and central lymphatics
Kerley B lines - perpendicular lines to the pleura that are thickened interlobular septae; 1 - 2 cm
Kerley C lines - Oblique lines, might be posterior Kerley B lines ; reticular lines at lung bases

Question 7

What are the radiological signs of alveolar oedema stage?

Answer 7

1. Consolidation
2. Air bronchogram
3. Pleural effusion
4. Central haziness that fades out peripherally (bat’s wing)

Question 8

What is the possible nature of the fluid of pleural effusion? Give example of causes.

Answer 8

1. Transudate - protein < 30g/L ; LDH < 200IU ; pH > 7.1
   Causes : heart failure, cirrhosis, nephrotic syndrome
2. Exudate : protein > 30g/L , LDH > 200IU ; ph < 7.1
   Causes : Pulmonary embolism, Pneumonia (infection); Bronchial Carcinoma