Radiography of the heart Flashcards
What are the types of cardiac chamber enlargement?
Concentric hypertrophy is a likely response to increased afterload (e.g., affecting the left ventricle as a result of aortic stenosis).
Eccentric hypertrophy is a likely response to increased preload (e.g., affecting the left ventricle as a result of patent ductus arteriosus or mitral insufficiency). Dilation is a likely response to chronically increased preload and is associated with cardiac failure.
Which types of dog are easy to falsely classify as having cardiomegaly
puppies, brachycephalic breeds, or obese dogs because these dogs usually have a relatively broad, rounded cardiac silhouette
What is tentatively considered a normal VHS?
8.7 - 10.7
Outline assessment of the pulmonary vessels
In each pulmonary lobe, the lobar arteries and
veins are normally equal in diameter and slightly
smaller than their accompanying bronchus in an
inspiratory radiograph. In a lateral radiograph, pulmonary veins are ventral to their corresponding lobar artery; in dorsoventral or ventrodorsal radiographs, pulmonary veins are medial to the corresponding lobar artery. Pulmonary congestion may be recognized radiographically when the pulmonary veins appear larger than either the corresponding lobar artery or the bronchus
How can you assess the right cranial lobar vessels?
The right cranial lobar vessels are normally thinner than the thinnest part of the right fourth rib,
What are the stages of pulmonary vessels congestion?
Initially, edema fluid leaks into the loose tissue around pulmonary vessels and bronchi, and its radiographic appearance may mimic bronchial wall thickening.
There is a tendency for edema to collect first at the
hilum, although this may be difficult to recognize
radiographically because the hilar region may already
have an increased opacity as a result of superimposition of enlarged vessels and the left atrium.
Edema fluid then accumulates in the alveolar septa, which become thicker, producing a hazy, diffuse interstitial pattern. Finally, fluid leaks through the epithelium of the alveolar ducts and floods the alveoli. If sufficient alveoli are flooded, the lung appears consolidated (sometimes with air bronchograms) and therefore is classified radiographically as an alveolar
pattern
What are the signs of CHF on rads?
Cardiomegaly Left Atrium enlargement Pulmonary venous distention Pulmonary oedema pleural effusion ascites Increased sternal contact (increases with R ventricle enlargement or significant L ventricle enlargement
On the DV view, where are the different chambers?
12-1 = Ao 1-2 = Pulmonary artery 2-3 = left auricular appendage
3-6 = left ventricle 6-9 = RV 9-12 = RA
What is the cowboy leg sign?
When the LA is enlarged on a DV view
The left and right principle bronchi normally have a split at approx 60 degrees, in LA enlargement it goes to up to 90 - cowboy legs split further apart
How can you assess the pulmonary vessels?
Veins are ventral veins are central
On DV, compare the vessels either side of the bronchus at the level of the 9th rib
Do on the left side of the body to avoid the vena cava confounding things
How can you subjectively assess the heart on an echo?
Ventricular size and wall thickness LA size - should be square, no bigger than L V LV systolic function Valve morphology LV should be elliptical
What is the triple knuckle sign on a radiograph?
Bulges at 12-1,1-2, 2-3 (e.g. Ao, PA, lAu)
Suggestive of PDA
What is the reverse D sign?
reverse D on RHS of heart on DV
Suggest RHS cardiac enlargement
What are the signs of pulmonary hypertension on rads?
LHS failure
Increase in size of the pulmonary arteries
RHS heart enlargement
Bulge at the place of the pulmonary artery on the heart.
Why may dobermans be hard to see cardiomegaly on?
Often can appear as an elongation on lateral
As deep chested may not look enlarged when it is
