Cardiovascular Flashcards
Causes for a murmur?
Puppy murmur
Anemia
Fever
High sympathetic tone
Hyperthyroid
Marked bradycardia
Peripheral AV fistulae
Hypoproteinemia
Athletic hearts
Hypertension
15-34% of healthy cats
Normal VHS for most dogs?
8.5-10.5
Normal VHS for Minie Schnauzer, greyhounds and whippets?
Exceed 11
Normal VHS for boxers?
12.6
Upper VHS for long thorax like Dachshund?
9.5
VHS for cats?
6.7-8.1
What caudal mainstem bronchus is commonly elevated with LA enlargement?
Left
Pulmonary edema with relatively normal LA size think what?
Rupture Chordae tendinae.
The S1 heart sounds originates from?
Closure of AV valves
The S2 heart sounds originate from?
Closure of the aortic and pulmonic valves
Speed of sound?
1540 m/sec
How does the ultrasound beam get attenuated? 4 things?
Beam divergence Absorption Scatter Reflection
Common range for echocardiogram (MHz)?
3.5-10MHz
What is a MHz?
1 million cycles/sec
Sedation that can be used in dogs and cats?
Ace
Butorphaol
Buprenophine
Ket if needed.
Most common views?
Right and left parastenal.
RV wall should be no greater than what of the LV free wall?
1/2 thickness
Size of the LA in cats in long axis (right ) view?
1.5cm - 1.9cm = greater risk for thromboembolism.
M-mode provides a cleaner resolution of the cardiac borders than 2-D due to what?
Higher sampling rate.
What is M-mode showing/measuring in this parasternal short axis view?
E-Point septal separation
Fractional shortening
LA: Ao ratio
What is FS and what are normals for cats and dogs?
FS = Left ventricular internal dimension diastole - LVID systole/ LVIDd (x100)
25-45% in dogs
Cats 35-65%
What happens to E point and A point at high heart rates?
They blend together
E is the point of maxium opening during rapid ventricular filling
F is when it starts to close
Then A happens when the atrium contracts.
What does increase e-point to septal separation usually assoicated with?
Reduced myocacrdial contractility
M-mode LA: Ao ratio?
1:1
Theory of saline microbubbles in echocardiogram?
Injection IV then they go to the right heart… they do not cross through the pulmonary capillary bed and therefore should not be seen in the left heart.
If in the left heart than there is a right to left shunt.
In doppler sound returning from cells moving away from the transducer has what type of frequency? Towards the transducer?
Low frequency - Away from the transducer
High frequency - Towards the transducer
The angle of the beam to the flow of blood should be less than what? What happens at 90 degrees?
20 degrees or less
At 90 degrees = 0 so no flow.
What is the advantage of pulse doppler? Disadvantage?
The blood flow velocity, direction and spectral characteristics can be caluclated from A SPECIFIC LOCATION!
Disadvantage - there is a velocity limit. (2x the pulse repetition frequency or Nyquist limit)
What can effect the Nyquist limit?
Lower frequency transducers
Closer sample volume placement
Both increase the nyquist limi.
On a Pulse waved doppler (PW) what direction is below base line? Above base line?
Below base line = away from transducer
Above base line = towards the transducer
What are the best views for the inflow velocities of the mitral and tricupsid valves?
Mitral - Four chamber left parasternal
Tricuspid - left cranial short axis
What is the peak ejection aortic and pulmonary velocity?
Pulmonary - 1.4-1.5 m/s
Aortic 1.6-1.7 m/s — Highest 2.0
Peak injection velocity of what across the aortic valve is consistent with aortic stenosis?
2.2 m/s
between 1.7-2.2 is the Gray zone!
Best views for pulmonary velocities and aortic velocities?
Pulmonary: left cranial view
Aortic: Subcostal or left apical view (pick the highest velocity)
Advantage and disadvantage of continuous doppler (CW)?
No max velocity - advantage
Range ambiguity (no idea where the velocity is coming from) - Disadvantage.
What is the the modified bernoulli equation?
P = 4v2
When do you use pressure gradient estimation?
Regurgitant jets of the pulmonary valve.
PH (measuring of the tricuspid jet) should be assoicated with what velocity/pressure ?
3.5-50mmHg or 2.9-3.5m/sec – Mild
51-75mmHg or 3.6-4.3m/sec — Moderate
>75mmHg or >4.3m/sec — Severe
In color flow (CF) what do the two colors indicate?
Red - Towards
Blue - Away
Black - No flow or perpendicular
Aliasing in CF doppler is seen as what?
Reversal of color (shifting)
What are the CF characteristics commonly associated with more severe regurgitation?
Wide and long jets
Cardiac troponins are attached to cardiac actin filaments and are released (leaked) when what happens?
Myocardial injury
What breed has a higher than normal cardiac troponin?
Greyhounds
NTproBNP evelation correlates with what?
Severity of cardiac disease
and can help differentiate CHF vs noncardiac causes of dyspnea
What can cause elevated NTproBNP artifically?
Azotemia
Most common congenital diseases in dogs?
PDA and SAS
Pulmonary stenosis is also common.
An endocardial cushion consists of what?
High VSD
Low ASD
Malformation of one or both AV valves
Most common congenital heart diseases in cats?
AV valve dysplasias
Atrial or ventricular septal defects
Congenital malformations are more prevalent in what breed of cats?
Males
Congenital malformations are more prevalent in what group of animals?
Purebreds
All congenital heart defects are seen in large breed dogs except for which ones?
Mainly PDA (Mixed group of little and big)
Pulmonic stenosis (Mixed group of little and big)
Histopathologically a PDA has what changes that don’t allow it to close?
Less smooth muscle.
How many dogs with PDAs get reverse PDAs? Why does this happen?
15%
Pulmonary vascular changes and creates high resistance and then pulmonary hypertension and therefore pressures rise over the aortic pressure thus reversing flow.
PDAs have a 2-3x higher prevelance in what sex?
Female— opposite of what you normally think of congential heart defects
What are the clinical signs with PDA?
Most are asymptomatic when first diagnosed
Others = Cough, tachypnea, exercise intolerant.
What is the classic triad of bulges for a PDA?
Left auricle
Pulmonary trunk
Aorta
Most helpful echocardiogram view for finding a PDA?
Left cranial short axis
DOPPLER FLOW
What is this?
PDA
Why is it contraindicated to close a reversed PDA?
It is acting as a pop off valve for the pulmonary hypertension… there for if it closes then the right heart pressures will go up and probably go into heart failure.
What type of heart remodeling is seen with valvular stenosis?
Concentric due to increase pressure.
What is this?
This is a PDA.. see the turbulance in the pulmoonary outflow and the arrow is pointing to the PDA.
What is the most common type of aortic stenosis?
Subaortic stenosis
What is commonly compromised in aortic stenosis that can lead to progression of hypertrophy and myocardial ischemic fibrosis?
Coronary perfusion
Why are animals with SAS thought to be a higher risk for aortic valve endocarditis?
The jet causes a lesion injury to the underside of the valve.
What is this?
SAS
What view is the best for seeinig velocities out of the aortic outflow for SAS?
Subxyphoid.
What is considered abnormal for aortic flow?
Over 2.2 m/sec is abnormal
1.7-2.2 m/sec is grey zone. (Normal in boxers, Goldens and Greyhounds)
What echo signs are there for SAS?
Stenosis of the outflow tract
Poststenotic dilation
Increased LV echogenicity (fibrosis)
Aortic thickening
LA enlargement
LV thickening.
Pulmonic stenosis is more common in what size of dog?
Small
With stenotic lesions what cause dynamic obstruction?
Severe enlargement of the myocardium just below the valve (infundibular region)
A combination of pulmonic stenosis and what can causes right to left shunting?
PS + ASD or paten foramen ovale
The pressure from the PS allows the blood pressure in the RV to be big enough to overcome the left.
What defect is important to look for in Boxers and bulldogs with PS?
Anomalous coronary artery (R2A) which wraps around the pulmonary artery thus if ballooned will kill the dog.
When does syncope or cyanosis happen in dogs with pulmonary stenosis?
When there is a concurrent VSD or ASD causing right to left shunting.
What is this?
Pulmonary stenosis
When is PS considered severe?
100mmHg jet.
The prognosis for pulmonary stenosis is worse with what other findings?
Tricuspid regurgitation
Atrial fib
Tachyarrhythmias
CHF
Where are most VSD located?
The membranous part of the septum just below the aortic valve.
VSD cause volume overloading of what side of the heart?
Left side
Very large VSD causes ventricles to function as what?
A common chamber and induces RV changes.
Best view to see a VSD?
Right parasternal long axis
Small VSDs will cause high-velocity shunting with what velocity and why is this important?
4.5-5m/sec
Important due to prognosis.. smaller VSD is better so higher velocity is better.
What is this?
VSD
What can low peak shunt velocity in a VSD mean?
Large VSD
Pulmonary hypertension
Pulmonary stenosis
How can a VSD close?
Spontaneously
The left heart hypertrophies so much it closes it
Sealed by a tricuspid leaflet or aortic leaflet.
Where are ASD most likely to be located in a dog vs cat?
Dog - fossa ovale
Cat - Lower septum
ASDs cause volume overload of what part of the heart?
Right side… due to the left to right shunting in the atrium
Why are ASDs hard to find on doppler?
Thin fossa ovalis region may look like one
Venous inflow can cause doppler to suck
Mitral dyplasia is commonly seen in what animals… why is this important?
Large young dogs
Cats
In dogs this important because of the fact that we call cardiomyopathy in big dogs with big left hearts… Therefore this should also be on the list if it is a young dog.
Tricuspid dysplasia is most common in what type of dogs?
Labs (large breed dogs)
What is the most common finding in these dogs and cats on rads?
HUGE right hearts - DDX pericardial effusion and DCM
What are the most common cardiac anomalies that cause cyanosis?
Tetrology of fallot
Pulmonary hyerptension secondary to PDA, VSD or ASD
What is tetralogy of fallot (T of F)?
VSD
Pulmonary stenosis
RV hypertrophy
Malpositioned aorta (over the septum causing right to aortic shunting)
What breed is predisposed through inheritance to T of F?
Keehond.
What is this?
Tricuspid dysplasia
What is this?
Reversal of a PDA
The first image is in the LV and looks normal, the second is in the RV and the aorta is opacified. The LV or LA is not ruling out VSD or ASD reversal.
Malformation that allow deoxygenated blood to reach circulation (Right to left shunting (reversals or T of F)) cause what?
Hyperviscosity syndrome secondary to erthrocytosis secondary to hypoxia.
What is the most common vascular ring anomaly in dogs?
PRAA
What is cor triatriatum?
Membrane divides the right or left atrium into two chambers
What is cor triatriatum sinister vs dexter?
Sinister = left atrium
Dexter = right atrium
What is the main radiographic sign of cor triatraum dexter?
Enlarged CVC with no heart enlargement.
What cat breeds get endocardial fibroelastosis?
Burmese and siamese
Left sided changes.
Chronic valvular disease is the cause of what percentage of heart disease in dogs?
70%
- What breed of large breed dogs may have a higher prevalence of mitral valve degeneration?
- Labs
- Great Dane
- Rotties
- GSD
GSD
- What are causes of acutely worsening pulmonary edema in dogs with chronic AV valve disease?
- Arrhythmias
- Increased cardiac load
- Hot, humid environment
- Ruptured chordae
All of them
- What bronchus is commonly associated with collapse in dogs with AV valve disease?
- Caudal right
- Right middle
- Left cranial
- Caudal left
left caudal bronchus
- What is the maximal TR regurg jet velocity allowed before it is considered abnormal?
- 1.7m/s
- 2.0m/s
- 2.2m/s
- 2.5m/s
2.2m/s
- What are potential sequelae of infectious endocarditis?
- Infarcts (splenic, renal)
- Immune-mediated polyarthritis
- Myositis
- Pneumonia
- Thrombosis
All of them
- What congenital heart disease has an increased risk for infectious endocarditis?
- PDA
- VSD
- Tricuspid dysplasia
- SAS
SAS
- T/F Hypertrophic osteopathy has been associated with bacterial endocarditis?
True
What is the common bacteria that causes endocarditis?
Bartonella.
What dog breed has the highest prevalence of DCM?
Dobies.
DCM in dogs commonly causes what type of heart enlargment?
Left sided.
What is the criteria for occult DCM on echocardiogram?
LVIDd greater than 4.6cm <42kg
5.0cm >42kg
LVIDs >3.8cm
VPCs
EPSS >0.8cm
- What chemo drug commonly cause secondary myocardial disease?
- 5FU
- Chlorambucil
- Doxorubicin
- Vincristine
C and A
- Strict vegetarian diet can cause secondary myocardial disease due to the lack of what nutrient?
- Vit C
- L-carnitine
- Taurine
- Vit B
L-carntine
- Atherosclerosis of the coronary arteries is cause by what endocrine disease?
- Hypoadreno
- Hyperadreno
- Hyperthyroid
- Hypothyroid
Hypothyroid
- What viruses can cause myocarditis in dogs?
- Coronavirus
- Distemper
- Rabies
- West Nile
- Parvovirus
Distemper
WN
parvo
- Noninfectious myocarditis can be caused by what?
- Thyroid homone
- Wasp venom
- Immune mediated disease
- Phyochromocytoma
All of them
- What is a major complication off cats with myocardial disease?
- Coronary infarction
- Right atrial rupture
- Arterial thromboembolism
- Endocarditis
Arterial Thromboembolism
- HCM is most common in what type of cat?
- Old, female
- Middle age, female
- Old, male
- Middle age, male
Middle aged males
- What is the normal FS for a cat?
- 25-65%
- 35-55%
- 35-65%
- 25-55%
35-65%
- Who knew there was steroid-associated heart failure in cats?
- Me
- Not me
Not me
Where are the four most clinically recognized places for a thromboembolic event?
Cranial vena cava
Distal aorta
Pulmonary arteries
Heart
What are the three things in Virchows triangle?
Endothelial damage
Stasis of blood
Hypercoaguability
The common reason for cats to get PTEs is?
HWD
A LA dimension of what may have increased risk of TE disease?
- 1.2mm
- 1.5mm
- 2.0mm
- 2.2mm
2.0mm
What is the difference between the clinical signs in dogs with an aortic thrombus and a cat?
- Dogs are usually bilateral, while cats are usually unilateral
- Dogs commonly show signs of self-mutilation and cats do not
- Dogs have chronic signs while cats are acute
- This disease is common in young dogs while it is common in older cats
Dogs have chronic clinical signs
What does claudication mean?
- Cold feet secondary to ischemia
- Blue/white appendages secondary to ischemia
- Muscle pain secondary to ischemia
- Sloughing of tissue secondary to ischemia
Muscle pain secondary to ischemia
List the four target organs in chronic systemic hypertension?
Heart
Kidneys
Eyes
Brain
An proximal ascending aortic diameter:aortic valve annulus diameter ratio is commonly seen in cats with systemic hypertension?
- 1.05
- 1.75
- 2.25
- 1.25
1.25
What group of dogs can have normally higher blood pressure than other breeds?
- Basset hounds
- Terriers
- Labs
- Sighthounds
Sighthounds
What factor has been associated with high blood pressure in dogs and cats?
- Brown eyes
- Athletic event animals
- A raw food diet
- Obesity
Obesity
