FM Radiology Case - Congestive Heart Failure

Question 1

What are the characteristic pathologic features of the heart in CHF?

Answer 1

1. Enlarged heart
2. Changes in cardiac chambers and myocardium (depending on etiology)
3. Irregular fibrosis replaces myocardium

Question 2

What are the characteristic pathologic features of the lungs in CHF?

Answer 2

1. Severe, chronic passive congestion of the lungs
2. Vessels, including alveolar capillaries, are congested as a result of pulmonary venous hyeprtension
3. Alveoli contain numerous hemosiderin laden macrophages

Question 3

What causes the frothy liquid seen from the cut surface of the lung in CHF?

Answer 3

Air moving through water in the respiratory tree

Question 4

List some of the anticipated CXR findings in a patient with CHF.

Answer 4

1. Cardiomegaly
2. Vascular Phase (phase 1) - cephalization, hilar fulness with haziness
3. Interstitial Phase (phase 2) - kerley lines
4. Alveolar phase (phase 3) - butterfly distribution, pulmonary edema
5. Pleural effusions

Question 5

Define cardiomegaly on CXR.

Answer 5

If the transverse diameter of the heart is larger than the diameter of the hemithorax; cardiothoracic ratio >0.5

Question 6

What are the phases of congestive heart failure?

Answer 6

1. Vascular phase
2. Interstitial phase
3. Alveolar phase

Question 7

What happens pathophysiologically in the vascular phase of CHF?

Answer 7

Pulmonary venous hypertension

Question 8

What is cephalization?

Answer 8

The vessels in the upper chest are more prominent due to pulmonary venous hypertension (opposite of normal); increased (>1) artery:bronchus ratio at hilar level

Question 9

What causes hilar fulness with haziness?

Answer 9

Enlarged pulmonary veins with perivascular fluid collection

Question 10

What happens pathophysiologically in the interstitial phase of CHF?

Answer 10

Interstitial edema and increased lymphatic drainage

Question 11

What are kerley lines?

Answer 11

2-3cm long horizontal lines in the base of the lungs close to the chest wall

Question 12

What is seen on CXR in the Alveolar phase?

Answer 12

Bilateral diffuse soft fluffy alveolar infiltrates coalescing with each other in a butterfly distrubtion

Question 13

What happens pathophysiologically in the alveolar phase of CHF?

Answer 13

Pulmonary edema

Question 14

Why might a normal sized heart be seen on CXR during CHF?

Answer 14

CHF secondary to an acute MI

Question 15

Compare the CXR of acute vs. chronic CHF.

Answer 15

Acute - pulmonary edema (alveolar phase)

Chronic - all 3 phases + pleural effusions

Question 16

What is gravity-dependent accumulation of fluid in the lungs and alveoli?

Answer 16

Basal congestion

Question 17

What causes pleural effusions?

Answer 17

Increased hydrostatic pressure

Question 18

Compare CHF and pulmonary edema.

Answer 18

CHF - basal congestion (dependent)

Pulmonary edema - diffuse white out of lungs

Question 19

What are the steps in reading a CXR suspected to have CHF (chronic)?

Answer 19

1. Determine PA vs. AP view - many of the findings will change in AP film
2. Decide on the transverse diameter of the heart
3. Look for pleural effusion.
4. Compare the diameter of the vessels in the upper 1/3 of the lungs to the lower 2/3.
5. Comapre the size of the end on view of vessel to the adjacement bronchus
6. Look for hilar fullness and congestion
7. Look for kerley lines
8. Look for basal congestion

Question 20

What are the steps in reading a CXR suspected to have CHF (acute)?

Answer 20

1. Heart may be of normal size
2. Diffuse white out of lungs
3. Butterfly pattern - medullary or central distribution of density
4. Will NOT see findings noted in chronic CHF

Question 21

How to distinguish CHF CXR from other acute alveolar disease? - Hemorrhage

Answer 21

Hemoptysis, sudden drop in Hgb

Question 22

How to distinguish CHF CXR from other acute alveolar disease? - ARDS

Answer 22

1. Prior major event (trauma, bleeding, sepsis, etc.), progressive hypoxia resistant to therapy requiring ventilator management
2. Normal heart size, no pleural effusion

Question 23

How to distinguish CHF CXR from other acute alveolar disease? - Pneumonia

Answer 23

High fever, oddball infections (influenza, mycoplasma, pneumocystis)