Large animal cardiovascular disease Flashcards
How do LA cardiac ptx usually present?
often non-specific clinical complaint
decreased muscle mass or milk production
increased resp. rate/effort
decreased exercise tolerance
What is crucial info when approaching LA cardiac ptx?
signalmnt
onset
duration/progression of chief complaint
diet and supplements
housing envr.
repro status
deworming programme
hx of illness
presence of other animals with similar signs
What does pale mucous membrane indicate?
anaemia
decreased CO
What does hyperaemic mucous membranes indicate?
secondary to spesis
peripheral vasodilation
hyperdynamic output
What does prolonged CRT indicate?
diminished cardiac output and/or shock
What can jugular pulses/fill indicate?
pulses higher than lower 1/3 are abnormal
distention and increased pulsation: Rheart abnormality/arrhythmia
What does ventral (brisket) oedema indicate?
common sign of heart failure (R>L)
What do hyperkinetic pulses indicate?
increase systolic pressure, decreased diastolic pressure or both
What do hypokinetic pulses indicate?
diminution of cardiac output, systemic vasodilation in shock
What does muffled sounds indicate on auscultation?
pericardial/pleural effusion
What does washing machine murmur indicate on auscultation?
gas/fluid/fibrin within pericardium
What is pericarditis?
inflammation of the pericardium that results in fluid/exudate accumulation between visceral and parietal pericardium
What are the causes of pericarditis?
trauma
haematogenous spread (septicaemia)
extension of lung/pleural infection
viral infection
neoplasia
mare reproductibe loss syndrome: actinobacillus
idiopathic
What is traumatic reticuloperitonitis?
TPR is from penetration of the reticulum by a foreign body
What are the possible outcomes of an ingested object in LA?
- attach to magnet previously administered
- penetrate reticular wall without entering peritoneal cavity causing focal reticulitis/mild dz
- perforate reticular wall/entrance to peritoneal cavity causing acute localised TRP
- perforate reticular wall/entrance to peritoneal/thoracic cavity causing pericarditis, myocarditis, abscess, vagal indigestion, etc.
What are the early clinical signs of traumatic pericarditis?
fever
anorexia
depression
cranial abdominal, reticular, thoracic pain
elbows abducted, reluctant to move
positive williams test, bar test and pinch test
What are the later signs of traumatic pericarditis?
Rsided constrictive heart failure
venous congestion
peripheral oedema
What are the cardiovascular clinical signs of traumatic pericarditis?
tachycardia
muffled heart sounds
+/- washing machine murmur
venous distention
raised jug pulse
waek pulses
What are the consequences of fluid in the pericardial sac?
leads to cardiac compression
when pressure in sac is greater than heart = reduced ventricular filling and diastolic dysfunction
RCHF
What is the use of bloodwork, xray and ultrasound in diagnosing traumatic pericarditis?
Blood: suggestive but absence of abnormalities doesnt rule it out
xray: limited to referral practices, useful to ID FB, see enlarged heart
US: dtecet abnormal reticular body, pericardial effusion
What is the tx for traumatic pericarditis?
removing FB or preventing further trauma/penetration (magnet)
thoracotomy and marsupialisation of pericardial sac with lavage and debridement
What is the most common cardiac tumour in LA?
lymphosarcoma
What are the clinical signs of cardiac neoplasia?
Nonspecific: depend on site of tumour and other sites of manifestation
anorexia, depression, weight loss, fever
What are signs of cardiac neoplasia when there is pericardial involvement?
tachycardia
pain
jugular distention
peripheral oedema
weak pulses
What are the signs of cardiac neoplasia when there is myocardial involvement?
tachycardia
cardiac arrhythmias
cardiac murmur
CHF: peripheral oedema, ascites, diarrhoea
What causes lymphosarcoma in cattle?
bovine leukemia virus
cardiac involvement common with adult/enzootic form
NOTIFIABLE DISEASE
What are the common characteristics of lymphoma?
predilection for RA myocardium
RAP increases, jug distention
pericardial effusion, often haemorrhagic
Rside HF
cytology w/neoplastic cells
What causes pericarditis in pigs?
haemophilus/glaesserella parasuis (glasser’s dz)
strep. suis
What are the clinical signs of pericarditis in pigs?
fever
depression
fibrinous poly serositis
effusions in CNS, pleura. peritoneum and synovia
What causes pericardial effusion in horses?
majority are idiopathic
minority are infectious
- equine viral arteritis (notifiable) equine influenza
- strep. pneumoniae, e.coli, actinobacillus equuli
- tend to develop fibrinous effusion
What are the clinical signs of pericardial effusion in horses?
venous distention
ventral oedema
muffled heart sounds
pericardial friction rubs (difficult to hear)
pleural effusion: dyspnoea, dullness on percussion, smaller lung field on auscultation
What tools can we use to diagnose pericardial effusion in horses?
echocardiography: fluid +/- fibrin in pericardial sac, compression of cardiac chambers
ECG: small complexes
Cytology of fluid
What is the tx and prognosis of pericardial effusion in horses?
repeated pericardial drainage and lavage +/- antibio esp. if RA is collapsing
good provided tx is early and aggressive
constrictive dz may occur in chronic cases
What is Cor Pulmonale?
secondary to pulmonary hypertension
leads to RV hypertrophy, dilation or failure
What are the causes of Cor Pulmonale?
High mountain disease/high altitude disease/brisket disease
chronic pulmonary disease
equine chronic/severe asthma
What are clinical signs of Cor Pulmonale?
subQ oedema of brisket, ventral thorax, submandibular areas and limbs
lethargy
weakness
bulging eyes
diarrhoea
collapse and death
jugular pulse/distention
dyspnoea, tachypnoea
Split S2
murmur: tricuspid regurg. or pulm. ejection
What is tx and prognosis or cor pulmonale?
if high altitude sickness, move to lower pasture
prognosis usually hopeless because of underlying chronic irreparable lung pathology
What are 3 types of vascular dz?
aneurysms
embolism
thrombosis
What are aneurisms?
vascular dilations: weakening of outer elastic coat of blood vessels
What causes aneurysms?
trauma
sepsis
parasites
ageing
degenerative vascular disease
What is an embolism?
foreign material carried in the bloodstream
What causes embolism?
often from thrombus but can include catheters and other FB
What is thrombosis?
formation of clot that obstructs blood flow in the circulatory system
What causes thrombosis?
trauma
venous stasis
catheterization
needle penetration
thrombogenic solutions
bacterial contamination
cellulitis
lymphangitis
What is thrombophelbitis in horses?
pain, swelling thickening of vein
ususally associated with catheter or after its removal
When are horses more at risk for thrombophlebitis?
if animal is sick or hypercoagulable state
What are signs of thrombophlebitis?
pain
swelling
thickening of vein
bilateral jugular veneous thrombosis can lead to marked swelling of head
can lead to embolism/showering fever, murmur
What is the tx for thrombophlebitis?
remove catheter
hot packing
broad spectrum AB
anti-inflammatory drugs
anti-coagulant therapy
Why is prompt tx of bacterial endocarditis vital?
large proliferative “vegetative” lesions may develop, limiting prospects for return to normal valve function
What organisms cause bacterial endocarditis in ruminants?
enterococci
streptococci
actinomyces pyogenes
What area of the heart is affected by bacterial endocarditis in ruminants?
tricuspid and pulmonc valves
RV endocardium
What organisms cause bacterial endocarditis in horses?
pasteurella
actinobacillus
streptococci
rhodococcus equi
What areas of the heart are affected by bacterial endocarditis in horses?
mainly mitral and aortic (mitral more)
tricuspid valve usually only following jugular thrombophelbitis
What organisms cause bacterial endocarditis in pigs?
staph aureus
actinobacillus suis
erysipelothrix rhusiopathiae
What area of the heart is affected by bacterial endocarditis in pigs?
mitral, aortic
usually PM findings
What are the clinical signs of bacterial endocarditis?
CHF with murmur
fever
cardiac murmur
tachycardia
tachypnoea
What is the lab findings with bacterial endocarditis?
hyperfibrinogenaemia/SAA
anaemia
leucocytosis
What is the tx for bacterial endocarditis?
broad spectrum AB based on sensitivity
tx of farm animals usually not economically viable
What is the prognosis for bacterial endocarditis?
guarded even after bacterial cure
permanent structural damage to valve
septic emboli may shed to distant sites
What is Equine Exercise Induced Pulmonary Haemorrhage (EIPH)?
bleeding from lungs during exercise
blood detected on trachea-bronchoscopic exam after exercise or RBC in bronchoalveolar lavage fluid
What does EIPH cause?
accumulation of varying volumes of blood in pulmonary interstitium and airways
occurs in majority of thoroughbred and standardbred racehorses and in many others undergoing strenuous exercise
What are the clinical signs of EIPH?
Epistaxis
poor performance
US/XR changes to thorax
coughing
increased RR
resp. distress
behavioural changes
What happens pathophyiologically in EIPH?
pulmonary capillary stress failure, the capillary transmural pressure exceeds the threshold value
during exercise circulating blood volume can increase up to 50% due to splenic reserve of RBCs
What part of the lungs is primarily affected and why in EIPH?
caudo-dorsal lobes
higher blood flow
mehanical forces highest
displacement of diaphragm causes fall in alveolar pressure = greater transmural capillary pressures
What are predisposing conditions to EIPH?
in young TBs its a physiological response to strenuous exercise
prevalence increases with age and in males
conditions that increase pulmonary vasc. resistance: lower resp tract dz, upper resp tract obstruction, cardiac dz
How do we treat EIPH?
identity + tx any predisposing URT, LRT, cardiac dz
break haemorrhage-inflammation cycle (modify training, dust-free, furosemide)
What is the prognosis of EIPH?
good to fair if spontaneous and has minimal impact on performance or if associated with resp. infection/predisposing cause that can be identified + treated
poor for idiopathic bleeders with performance limitations
