Smith 5 - Cardiovascular Flashcards
ASD is more common in
calves
VSD location
- mostly in the perimembranous septum
- just ventral to aortic valve
- <2.5cm
- seen on LVOT echo
loud, harsh, plateau shaped pan systolic murmur, PMI tricuspid area (R)
+ softer crescendo-descrendo holosystolic murmur in pulmonic area (L)
VSD murmur
crescendo-decrescendo shaped, low to moderate intensity, non radiating murmur PMI L heart base
innocent flow murmur
VSD shunt
L ventricle to R ventricle
continuous machinery murmur loudest in L ICS 3-4 at POS
PDA
- OR aortocardiac fistula in adult onset
PDA occurs in
foals - should close by 96 hrs
calves - very rare
major risk with PDA
pulmonary artery dilatation and rupture
Tetralogy of Fallot
- overriding aorta
- VSD
- obstruction of pulmonary flow (p stenosis)
- RV hypertrophy
how does tetralogy occur
abnormal development of the conal septum, pulmonic stenosis, septum can’t close (VSD)
loud pan systolic murmur w/ palpable thrill loudest in L ICS 3-4
+ band shaped tricuspid murmur
Tetralogy
-will be crescendo-dec (pulmonic Sten) or harsh plateau shaped (VSD)
holosystolic crescendo-decrescendo murmur at L heart base in a calf
ASD - patent formen ovale
persistent truncus arteriosus
one arterial vessel leaves the heart above a VSD; coronary and pulmonary aa.s and aorta arise from this
pseudotruncus arteriosis
pulmonary blood supply comes from bronchial arteries or a PDA
most common aortic anomaly in calves / foals
dextropositioning or transposition
heart located in the cervical region
ectopia cordis cervicalis
most common bacteria in endocarditis
strep, pasturella, actinobacillus, truperella pyogenes
murmur PMI L base ICS 4
holosystolic musical de-crescendo
aortic valve
murmur PMI L base ICS 3
pulmonic
tricuspid murmur
R ICS 3-4= horse
R ICS 2-3 = cattle
widely radiating musical murmur with honking quality
major mitral valve ruptured chordae tendinae
- respiratory distress!!
- acute CV collapse, pulmonary edema
crescendo mid-systolic to late-sys or holo-sys murmur with PMI over the mitral valve in a horse
MV prolapse
signs of MR on echo
increase LA and LV dimensions, rounded LV apex, pattern of L volume overload
- increased FS
- decreased contractility
lesions associated with triscupid regurg
cattle - bacterial endocarditis
horses - none
effect of lung dysfunction on the heart - pulmonary hypertension, RV hypertrophy / dilation / failure
cor pulmonale
primary cause of cor pulmonale in cattle
high mountain disease / brisket disease
-hypoxic vasoconstriction due to altitude
brisket disease
- hypoxic vasoconstriction due to altitude >6000 feet
- increased pulmonary vascular resistance and pulmonary hypertension
- R sided pressure overload
- jug vein distention and subcut edema
- calves and yearlings moved from low to high altitude
- fall and winter
PAP and HMD
PAP >49 at any elevation = greatest risk
PAP <35 at 5000 feet = good to breed
bacterial causes of myocarditis
staph aureus, strep equi, clostridium chauvoei, mycobacteria
viral causes of myocarditis
foot-and-mouth, EIA, EVA, e. flu, African horse sickness
nutritional causes of DCM
Vit E, selenium, or copper deficiency
CS of pericarditis
peripheral edema, jug distention and pulsations, tachypnoea or dyspnoea
- tachycardia
- muffled heart sounds + absent ventral lung sounds
ECG changes: decreased QRS amplitude, electrical alternans, ST segment elevation
pericarditis
eastern tent caterpillars
MRLS - also cause constrictive / fibrinous pericarditis
most common primary cardiac tumor
lymphosarcoma - right atrial myocardium in cattle, TR occurs
-die within 6 months
aortopulmonary fistulas and thoracic aortic rupture occur in what breed
Friesians - connective tissue disorder of the collagen or elastin?
spontaneous thromboembolism in horses
- parasites
- aorta, cranial mesenteric arteries
causes of arteriosclerosis in cattle
- excess VitD3 supplementation
- calcinogenic plants: solanum malacoxylon, centrum diurnal, or trisetum flavecens
cause of arteriosclerosis in horses
strongylus vulgaris
cattle usually have AF associated with
- GI disease
- have APCs
common cause of paroxysmal AF in horses
furosemide –> K depletion
murmurs >3/6 are present in __% AF cases
less than 50% in horses, even less in cattle
how to differentiate AF from sinus arrhythmia or second degree AV block
AF = no fourth heart sound audible
signs with V tach
jugular pulses + “bruit de cannon”
diagnosing myocardial injury
cTnI
CK- MB fraction >5%
diagnosing VT on ECG
4 or more VPCs
wide and bizarre QRSs
ECG findings with life threatening VT
- multifocal origin for VPCs
- torsades de pointes (Wide VT)
- “R on R” - r wave superimposed on the previous t
polycythemia and tetralogy
uncommon in foals and calves
common congenital cause of cyanosis
tetralogy
ASD is frequently
asymptomatic
most common valvular dz in the horse
aortic regurg with degenerative changes
most common valvular dz in cattle
pulmonic regurg with endocarditis
widely radiating murmur with a distinctive honking quality
major mitral valve chordal rupture
Severe aortic and mitral valve regurgitation can eventually cause
venous pulmonary hypertension.
effusive pericarditis
Consequences associated with physical presence of fluid
Removal of pericardial fluid is beneficial
constrictive pericarditis
Reduction in ventricular compliance due to fibrinous or fibrotic involvement of the pericardium or epicardium
Removal of pericardial fluid is of limited benefit
paroxysmal AF
converts to normal sinus in 24-42 hours on its own
the most common VSD location is
perimembranous located ventral to the tricuspid leaflet, and below the junction of the right and noncoronary cusps of the aortic valve
the most common congenital heart defect in horses is
VSD
