7.3.25 cardiac lecture IIIA Flashcards
Auscultation of the cardiac patient.
Start at point of maximum intensity (PMI) which is usually cardiac apex left side.
Ausculate both sides of the thorax of course.
4 valve areas in total
4 lung fields in total
Min. 30 sec for each area is good.
Mötskula also recommends listening to the cranial thoracic inlet as aortic valve stenosis can be heard there.
Minimum 2-3 min for skilled practitioner so longer for green.
Usefulness of radiography for the cardiac patient.
Is readily available, and you can see the following on xray:
– Cardiomegaly/cardiac chamber enlargement
– Evidence of pulmonary oedema
– Causes of respiratory signs
Indications for thoracic xray:
Cough, tachypnoea, dyspnoea, orthopnoea
Right lateral is always default for heart xray but always take 2+ views. But dorsoventral if dyspnea.
Indications for thoracic radiographs. (7)
■ Cough
■ Dyspnoea/tachypnoea
■ New heart murmur (assessment of cardiomegaly)
■ Collapse
■ Exercise intolerance
■ Geriatric profile
■ Staging for neoplasia
Mötskula recommends sternal recumbancy/DV for heart images as the heart is in a more natural position.
Technique for cardiac radiography?
Technique requires fast exposure to avoid breathing artefact.
Inspiratory Respiratory phase films for better detail!
Use the anti-scatter grid (hila) for >10 cm thickness targets.
Pay special attention to Positioning.
At least two views: Dorsoventral/ventrodorsal first to avoid collapse of dependent lung, then right lateral, then left lateral if needed or desired.
Watch out for rotation!
Right lateral is always default for heart xray but always take 2+ views.
Inspiratory vs expiratory films.
ALWAYS take your image on inspiration!
Your image can be dractically different if you don’t.
Tip: Breathe in synchrony with your patient in order to do this.
Whats this referring to?
Avoid rotation!
normal vascular pattern
pulmonary edema
pleural effusion
You need to know your lung lobes. Left side: two lobes: cranial and caudal, cranial be divided into cranial and caudal parts. Right side: cranial, middle, caudal, and accessory.
Small animal lung lobes.
Left side: two lobes: cranial and caudal, cranial be divided into cranial and caudal parts.
Right side: cranial, middle, caudal, and accessory.
Right-heart structures.
CrVC = cranial vena cava
PAS = pulmonary artery segment
LP = left pulmonary artery
RP = right pulmonary artery
CaVC = caudal vena cava
RA = right atrium
TV = tricuspid valve
RV = right ventricle
PV = pulmonary valve
ra = right auricle
seen in left lateral
Left-heart structures.
Aa = aortic arch
LA = left atrium
CVC = caudal vena cava
MV = mitral valve
LVI = left ventricular inflow
LV = left ventricle
Aot = aortic outflow tract
AV = aortic valve
Aor = aorta
seen in right lateral
Approximate location of heart chambers on a lateral radiograph.
Vertebral heart score.
VHS = short axis + long axis measured in vertebral units beginning at T4
- Measure the long axis (from carina to apex) and short axis (widest part of the heart).
- Place these measurements over the thoracic vertebrae starting at T4 and count how many vertebrae they span.
- Add BOTH values together.
- Normal VHS varies by species and breed (~8.5–10.5 in dogs, ~6.9–8.1 in cats).
Higher scores suggest cardiomegaly, requiring further evaluation.
Up to 10.5 is normal.
VLAS
MHS
2 other systems for evaluating cardiac size
VLAS = vertebral left atrial size
* Draw a line from the center of the tracheal carina to the dorsal border of the left atrium.
* Place lines/measurements over vertebrae from T4 just like in VHS.
MHS = manubrial heart size
* Measure the maximal cardiac height (base to apex) on the radiograph.
* Measure the length of the manubrium and calculate the ratio: MHS = Cardiac Height ÷ Manubrium Length.
4 causes of right atrial enlargement
Right sided heart failure
Tricuspid insufficiency
Cardiomyopathy
Right atrial neoplasia
4 causes of left atrial enlargement
Mitral insufficiency
Cardiomyopathy
Left ventricular failure
Congenital heart disease: MV dysplasia, PDA, Ventricular Septal Defect, atrial SD
6 causes of right ventricular enlargement
Secondary to left-sided heart failure
Tricuspid insufficiency
Cardiomyopathy
Cor pulmonale (RV enlargement)
Dirofilariasis
Congenital heart Dz: Pulmonic Stenosis, PDA, VSD, Tetralogy of fallot, TV dysplasia
4 causes of left ventricular enlargement
Mitral insufficiency
Cardiomyopathy
Congenital heart Dz: PDA, Aortic stenosis, VSD
High-output heart Dz: fluid overload, chronic anemia, obesity, chronic renal Dz, hyperthyroidism
Points to remember about cats’ radiographs. (4)
■ Their Heart is more elongated and elliptical in lateral view.
■ Cardiac silhouette is about 2- 2.5 intercostal
spaces on lateral view.
■ Heart tends to become more horizontal with
age.
■ On DV/VD view the heart is more oval and
thinner.
normal/vascular pattern
artery is always “on top”, vein is central or ventral
interstitial pattern
fluid in pulmonary interstitium
alveolar pattern
fluid where it shouldn’t be. interstitial is frequently on top of alveolar.
Radiographic change of CHF in dogs. (4)
■ Cardiomegaly
– Left atrial enlargement
■ Pulmonary venous distension
– Not always present
■ Interstitial pulmonary edema
– Peribronchial and interstitial changes
■ Alveolar pulmonary edema
– Air bronchograms
You MUST have LA enlargement due to the sequence of events.
Pulonary edema in dogs vs cats.
Dogs:
■ Interstitial edema in mild-moderate with clouding of pulmonary vasculature and a peribronchial pattern may be noted.
■ In dogs, typically Central perihilar region, progressing caudodorsally.
■ On DV/VD, commonly noted in right caudal lung lobe.
Cats:
■ Distribution is extremely variable. Can be Diffuse, non uniform; Diffuse & uniform or Multifocal.
■ Appearance variable, can have Concurrent alveolar changes, Concurrent bronchial changes and Presence of pleural effusion.
dog pulmonary edema
cat pulmonary edema
skeletally mature cat
inspiratory resp. phase in both
blood vessels at heart base are visible.
vessels closer to table are smaller due to shadow effect.
moderate cardiomegaly with a bronchial pattern
mature cat
good position
no significant rotation
lat image not big looking heart but VD image it looks big.
moderate cardiomegaly, bronchointerstitial to mixed pattern.
mature cat
position is okay
very slight rotation in VD
vessels visible
hazy cranial heart margin
air bronchograms caudal to heart (telltale for alveolar pattern)
moderate cardiomegaly, interstitial mixed pattern = CHF
Tx with furosemide.
mature cat
very hazy lungs
aerophagia
severe pulmonary edema
interstitial mixed? pattern
pulmonary edema in a cat
pleural effusion usually caused by
right-sided heart failure but in cats even left-sided can cause it.
How to tell which side a lateral image is on?
in right - crura parallel
in left - crura V shaped
miliary interstitial pattern
mets from primary neoplasia outside the thorax.
bronchial pattern
small-looking heart aka microcardia
(technically hypovolemia can cause it and Addison’s can cause that, always suspect Addison’s with small hearts. sedation of this patient would be dangerous if it has hypoadrenocorticism)
dog
hazy/cloud lung fields
interstitial pattern at least as cardiac silhouette is disappearing.
could be some alveolar pattern ventrally where you can see air bronchograms.
big blood vessels visible like they should be.
left atrium does not look very big.
sever interstitial pattern
big blood vessels obscured mostly
interstitial-alveolar mixed pattern perihilar distribution
left atrium very enlarged
the big blood vessels looke quite dilated
tx with furosemide, take new xray in an hour.
dog
severe alveolar pattern
trachea displaced dorsally
severe pulmonary edema
give furosemide asap
massive cardiomegaly
left atrial enlargement
bronchial compression dorsal of the heart (due to the heart pushing them up)
interstitial pattern
right atrial enlargement
westie
idiopathic pulmonary fibrosis
cardiomegaly
trachea elevated
enlarged left atrial margin
ddx pericardial effusion
or at least rule out with U/S before giving furosemide
in this case it was pulmonary edema
massive cardiomegaly
trachea extremely dorsally displaced
interstitial, maybe some alveolar pattern
pulmonary vein massively dilated
growth plates open, congenital dz
ddx: persistent ductus arteriosus (causes left-sided heart dilation and eventual failure unless surgically corrected)
this dog had PDA causing CHF
Advanced imaging in veterinary cardiology. (4)
■ Cardiac catheterisation
■ Fluoroscopy
■ Computed tomography
■ Magnetic resonance imaging
