Exam 2 - Food Animal Cardiology Flashcards
what is the normal heart rate of an adult cow?
60-90 bpm
what is the normal heart rate of a calf?
90-110 bpm
what is the most common congenital heart defect in cattle?
high ventricular septal defect
T/F: a newborn calf may have a innocent murmur present at birth similar to foals
false - foals can have a PDA up to 96 hours into life, but calves should not be born with a murmur
what is the most common arrhythmia seen in ruminants?
atrial fibrillation
if you have a ruminant present with atrial fibrillation, what else should you investigate?
look for gi disease!! common acid-base imbalance is metabolic alkalosis
what examples of gi disease can result in atrial fibrillation in a cow?
left or right displaced abomasum
intestinal obstruction
diarrhea
what metabolic abnormalities can be seen in a cow with atrial fibrillation?
metabolic alkalosis - low k, Cl, & sometimes Ca
why is the right av valve affected so much in cows with myocarditis/endocarditis?
the rumen is teaming with bacteria & liver abscesses can throw micro-emboli
what is the pathogenesis of myocarditis/endocarditis?
originates either hematogenously or extension of an adjacent infection (pericarditis)
what are some of the common etiologies of myocarditis/endocarditis?
foot & mouth virus
what are the common clinical signs of infectious myocarditis/endocarditis?
lethargy, variable fever, weight loss, tachycardia, may or may not have a murmur, & +/- signs of right sided heart failure
what diagnostics are used to diagnose myocarditis/endocarditis?
echo - difficult on adults, so the left side may provide better imaging, try to get to 3rd/4th ICS
CBC - helpful if bacterial
chemistry panel - look at albumin & globulin if edema is present, GGT, bilirubin, & creatinine may be elevated in heart failure
what may be seen on clin path in an animal with myocarditis/endocarditis?
inflammatory leukogram - not always
fibrinogen elevated - not always
increased creatinine & GGT - can be high in heart failure
a/g ratio < 0.6
what are potential sequelae of myocarditis/endocarditis?
liver abscesses & pneumonia
what is the etiology associated with myocarditis/endocarditis?
staph spp., strep spp., trueperella spp., & e. coli
bacteremia or septicemia can originate from what in myocarditis/endocarditis?
sources of chronic infection - chronic mastitis, foot rot, metritis, liver abscesses
rumen via ruminal acidosis
why does ruminal acidosis cause problems in the cardiovascular system?
when the rumen becomes acidotic, the normal bacteria present in the rumen is allowed to transcend the rumen wall into the blood stream which then can travel to the liver, heart, & lungs all of which can manifest in infection
what rumen bacteria can cause myocarditis/endocarditis?
coliforms, gram positives, & anaerobes
if there is a heart murmur present in a cow with endocarditis, where may it be heard best?
PMI - right av valve, 4th intercostal space
why is a blood culture typically not used for diagnosing myocarditis/endocarditis?
useful only if the sample is obtained before animals are on antibiotics - but this is often not the case as animals have often been started on a medication
how can you differentiate between pleural effusion & muffled heart sounds from pericarditis?
in pleural effusion, lung sounds will be absent ventrally, but heart sounds are present & radiate out
in pericarditis, extremely muffled, ‘adult PDA’, washing machine murmur
what is the etiology of pericarditis?
mycoplasma bovis
hardware disease
myocarditis/endocarditis
extension from the lungs
what are the clinical signs seen with pericarditis?
muffled heart sounds - difficult if not impossible to hear
washing machine murmur
tachycardia
pleural effusion vs. pericarditis
signs of right-sided heart failure - brisket edema & jugular vein pulse
what diagnostics can be used for pericarditis?
CBC/chemistry
echo
what is the mechanism of disease for cor pulmonale?
pulmonary hypertension - trash lungs/animal not acclimating well to high altitudes
pressure builds up in the capillary beds against the arteries because in low oxygen, constriction of the vessels occurs, so the arteries pump harder which leads to left-sided heart failure
what are the clinical signs of cor pulmonale?
right-sided heart failure - even though it’s technically left-sided, signs of right-sided are better appreciated
what diagnostics are used for pericarditis?
history, ruling out other diseases, & baermann test for lung worms
what is the only form of lymphoma in adult cows associated with BLV?
enzootic lymphosarcoma
what is the common anatomical site for enzootic lymphoma?
right atrium
if there are signs of cardiac lymphoma, but the animal is BLV negative, what do you suspect?
not a tumor - going to be an abscess or myocarditis
what diagnostics should be used for lymphoma?
BLV test
ultrasound - sometimes will see wall thickening
CBC - may be helpful, persistent lymphocytosis
what is the timing associated with enzootic lymphosarcoma?
adult form is 3-6 years
what are the clinical signs of bovine lymphoma with a tumor located in the right atrium?
right-sided heart failure signs
what are the clinical signs associated with right-sided heart failure?
jugular pulse that extends further than 3/4 the way up the neck when the head is held in a normal position
jugular vein doesn’t collapse below the point where held off
brisket edema - possibly up to the submandibular region
tachycardia
maybe a murmu
what toxins can cause clinical signs of right-sided heart failure?
ionophores - monensin
yew
oleander
gossypol
if you see black streaks in the heart at necropsy, what’s on your differential list?
clostridium chauvoei
plant toxicity - yew, oleander, & gossypol
myocarditis/endocarditis/pericarditis
what are the 4 causes given for edema in ruminants?
- increased hydrostatic pressure - cardiac
- decreased oncotic pressure - low protein
- vasculitis - increased vascular permeability
- blockage in lymphatic flow - masses within lymphatics or within the thorax
how can you rule out endocarditis of the heart valves?
listen for a murmur
how can you test for decreased oncotic pressure in ruminants?
check total protein, chemistry panel to look at globulins & albumin
how can you test for vasculitis in ruminants?
evidence of septicemia - do a CBC to look at the white cell count, fibrinogen, & look at conjunctival blood vessels to see if there are any bleeds or if hyperemic
how can you test for blocked lymphatics in ruminants?
use an ultrasound to look for masses in the cranial mediastinum
palpate peripheral lymph nodes
how can you test for a mass in the right atrium in ruminants?
need to rule out lymphoma - test for BLV & echo
how can you test for pericarditis in ruminants?
echo!!!
look for pieces of fibrin, suspect hardware disease
how can you test for pulmonary hypertension in ruminants?
lifestyle - environment of the animal, high altitude
pneumonia that is chronic & severe in nature
baermann test - rule out lung worms
what are the 6 differentials given to rule out edema?
- endocarditis of the valves
- decreased oncotic pressure
- vasculitis - increased vascular permeability
- blocked lymphatics -
- mass in the right atrium -
- pericarditis - increased hydrostatic pressure
- pulmonary hypertension
what is the pathogenesis of caudal vena cava syndrome?
rumen acidosis leads to spread of the bacteria to the liver where microemboli form & spread to form abscesses in the lungs
clots then form in the caudal vena cava resulting in congestion
animals can cough up blood & have respiratory problems
what is the pathogenesis of caudal vena cava syndrome?
- liver abscesses
- pneumonia
- myocarditis/endocarditis
- inflammatory mediators lead to small blood clots that are dispersed - seeding of organs leads to thrombus formation most commonly in the caudal vena cava
- lungs get showered & filled with abscesses
- abscesses rupture into airways/blood vessels & the animal coughs up blood
- sudden death
what is seen on this ultrasound of the liver?
big abscess
what is the major infectious cause of cardiac disease in swine?
erysipelas
what are the most common cardiac problems encountered in camelids?
congenital defects
this is a nail poking through the reticulum of a cow as seen on necropsy - what cardiac problem do you suspect it caused? what would you expect to see on an echo of the heart?
traumatic reticulopericarditis - hardware disease
fluid in the pericardial sac
what is the treatment plan for a cow with myocarditis/endocarditis?
long-term antimicrobials - broad spectrum, IV oxytetracycline SID & florfenicol
possibly lasixs
NSAIDs
what is the prognosis of myocarditis/endocarditis?
guarded to poor
if you get them before signs of full blown heart failure - may get them into recovery
what is this lesion?
BLV - lymphoma in the right atrium of the heart
what plant is this?
oleander - cardic problems
what plant is this?
yew
what is the toxin that causes cardiac disease in cattle that comes from this plant?
gossypol - cotton seed meal
