Large Animal Cardiology

Question 1

What are the contributing factors to cattle developing Bovine High Mountain Disease or pulmonary hypertension

Answer 1

-Genetics
-Pneumonia
-Migrating parasite larva
-high altitude
-poisoinous plants (Locoweeds- oxytropis and astragalus)
-nutrition
-Age
-illness
-body condition
-breed
-gender
-anything that leads to pulmonary hypertesion

Question 2

What is the pathophysiology of BHMD

Answer 2

1) Altitude induced pulmonary hypoxia
2) Pulmonary shunting and vasoconstriction
3) Pulmonary artery hypertrophy
4) Pulmonary hypertension
5) Right ventricular hypertrophy
6) Right Ventricular failure
7) Death

Question 3

Understand that at the present time the best means to identify those animals at risk for
BHMD:

Answer 3

Carry out a PAP measurement and cull those with high scores, i.e. >50mmHg

Question 4

What is the economical affect that BHMD has on the cattle industry in high elevations:

Answer 4

This disease can often cause losses of greater than 5% of the calf crop resulting
in hundreds of thousands of dollars loss per year for the cattlemen in high
elevation. It is most likely the major concern and most costly loss for high
altitude ranchers

Question 5

What is the use of PAP testing by high altitude ranchers

Answer 5

Trying to develop a genetically resistant herd to the effects of high altitude. By
utilizing the PAP test a rancher can use low testing PAP bulls to help minimize
BHMD losses in claves. To really attempt to control losses they may choose to
test all replacement females. This would then allow them to have an entire herd
that is genetically resistant to the effects of altitude

Question 6

known as Hardware Disease by the rancher, and why it carries both of
these names. The often foreign body results in a bacterial infection of the entire
thoracic cavity

Answer 6

Traumatic Reticuloperitonitis/Pleuritis, Fibrinous Pericarditis

Question 7

How might a rancher prevent Hardware disease

Answer 7

Hardware Disease is most often caused by a foreign object being ingested by the
animal, most commonly cattle but it has been seen in other animals. This object
is often metal and do to its weight falls to the lower portion of the stomach, most
commonly the reticulum were it penetrates the stomach wall and often the chest
cavity. Infection from the stomach contents then overwhelms the animal resulting
in death. This can often be prevented by using a magnet that is given orally.

Question 8

What is the flow of blood through the body and the direction of
flow starting at the right ventricle:

Answer 8

Right ventricle, pulmonary artery, lungs, left pulmonary vein, left atrium, left
ventricle, arteries of body, organs, veins of body, cranial/caudal Vena Cava,
right atrium, right ventricle. Understand how this flow may be associated with
the clinical signs of BHMD as well as endocarditis

Question 9

Where is endocarditis most common in bovines

Answer 9

most commonly found on the right side of the heart on the pulmonary
valve or the tricuspid

attle tend to develop periodical episodes of a bacteremia (bacteria in
their blood). This is often caused by concurrent illness or feeds much too high in
concentrates, grain. The bacteria then enter the blood stream, and now knowing
the flow of blood, you can see that the bacteria enter the right ventricle first and
begin to localize on the right tricuspid or pulmonary values. In humans and other
species the most common bacterial invasion of the body is from the lungs,
therefore entering the blood stream on the left side of the system invading the left
ventricle and its structures

Question 10

These negatively charged cations from Streptomyces cinnamonensis help in
feed efficiency by; increasing rumen propionate and decreasing acetate and
enhancing rumen nitrogen metabolism into protein. They also help in being
coccidiostatic. Besides these benefits Ionophores can be cardio-toxic by causing
an influx of Na+ into the cell which induces an influx of Ca++ into the cell which
often results in mitochondrial damage and cells death.

Answer 10

Inophores (Monesin)

Question 11

Increases rumen propionate and decreases acetate and enhances rumen nitrogen metabolism into protein

Answer 11

Inophores (Monesin)

Question 12

What are the effects of rattlesnake bites

Answer 12

Local edema and inflammation around the bite wound. Rapid swelling of the face
and airway if bitten in the nose resulting in respiratory failure.
Thrombocytopenia and coagulopathies. Local severe infection and cellulitis
resulting in tissue necrosis and sloughing.

Question 13

How do you approach a rattle snake bite in cattle

Answer 13

mergency supportive care including
oxygen therapy. Maintaining a functioning respiratory system by utilizing syringe
cases to keep nasal airway passages open or performing a tracheostomy.
Antibiotic therapy in hopes of preventing infection for the bite. Anti-
inflammatories, Laser therapy and Anti-venom may all be utilized.

Question 14

Vitamin E and Selenium deficiency in camelids causes

Answer 14

diaphragmatic paralysis and
respiratory death

Question 15

Lab finding of bovines with Vitamin E and Selenium deficiency

Answer 15

CK often being greater than 50,000 and have been seen as high as 500,000

Question 16

What is the therapy for bovines with Vitamin E / Selenium deficiency

Answer 16

herapy often is
vitamin E injection and oral supplementation. If selenium deficiency is suspected
further herd evaluation should be done and consider selenium supplementation or
treatment.
Practice Questions:

Question 17

At the present time the best means to identify those animals at risk for Bovine High
Mountain Disease (BHMD) is?
a. Genetically DNA match them and cull those that are possible carriers.
b. Take all animals to high elevations about 8000 feet and leave them for 1 month, keep
only those that are alive and well after that elevated altitude stress.
c. Carry out a Pulmonary Arterial Pressure (PAP Measurement) and cull those with
high PAP scores, i.e. above 50mmHg.
d. Carry out a PAP Measurement and cull out those animals with low scores, i.e. below
40 mmHg

Answer 17

C

Question 18

T/F: BHMD has little impact on the cattle industry in high elevations

Answer 18

False

Question 19

A ranch family wants to try to develop a herd that they can utilized in high elevation and
produce bulls that they can market for high altitude use. They know of the PAP test but
desire to know how it can best be used or can it be used for this type of situation. How is
the PAP test best utilized in this situation?
a. PAP measure/test all animals and identify those animals with pulmonary hypertension
and eliminate them, especially all replacement heifers and bulls used in their breeding
program.
b. Explain to them that a PAP measurement is a means to genetically select those animals
not experiencing pulmonary hypertension (low PAP measurements) with hopes of
developing a genetically resistant herd to the effects of altitude.
c. Explain to them that the PAP test/measurement can be used as a marketing tool and a
means of supply genetically resistant bulls to the buyers for high altitude use.
d. All of the above.

Answer 19

D

Question 20

Hardware Disease” as it is known by the rancher can best be described in medical
terminology as:
a. Traumatic Reticuloperitonitis/Pleuritis, Fibrinous Pericarditis
b. Lung Abscesses and infection
c. Rumenitis/Abomasitis

Answer 20

A

Question 21

Hardware Disease is most often caused by_________, and often is prevented by using
a_______.

Answer 21

metal foreign object; magnet

Question 22

You explain endocarditis most commonly affects
the ________ side of the heart in ruminants specifically the ________ valve. Often in
ruminant’s endocarditis can be and is most commonly associated with an __________
infection from the_______ associated with chronic acidosis secondary to a high
concentrate diet. Often ruminants with endocarditis will also have multiple bacterial
_______ abscesses. You recommend further work–up that may include,_______ and
______ _______ knowing neither may be 100% diagnostic. Treatment options at this
point may be long term ________ therapy with a guarded prognosis

Answer 22

right side of the heart in ruminants specifically the tricuspid valve. Often in ruminants endocarditis can be and is most commonly associated with a bacterial infection from the rumen associated with chronic acidosis secondary to a high concentrate diet. Often ruminants with endocarditis will also have multiple bacterial liver abscesses. You recommend further workup that might include echocardiogram and blood culture knowing neither may be 100% diagnostic. Treatment options at this point may be long term antibiotic therapy with a guarded prognosis

Question 23

What is associated with ruminant endocarditis

Answer 23

associated with chronic acidosis secondary to a high concentrate diet

Question 24

What else can help you diagnose Endocarditis in ruminants

Answer 24

You recommend further workup that might include echocardiogram and blood culture knowing neither may be 100% diagnostic.

Question 25

You are asked to look at a 3 month old Limousine heifer that has not done well her entire life. She is now 60 pounds lighter than the other heifers her age. On her physical exam you find her to have a T-99.0, P-186, R-60. On lung auscultation there are louder sounds in the lungs that you would expect for a calf this age. Her lung sounds are twice to volume of her trachea sounds. On the left side of her thorax over the pulmonary valve there appears to be an III/VI pansystoloic murmur. On the right side over the tricuspid value there is a VI/VI pansystoloic murmur with a palatable thrill. You ask the rancher if you can do a PAP test and the results you find are, PAP 140mmHg with a 160/104 systolic/diastolic. Your best diagnosis and prognosis at this time for this progressively poor doing heifer with these clinical findings?

Answer 25

Ventricular Septal Defect (VSD), since there are clinical signs at this time prognosis would be poor

Question 26

Which one of the following statements is correct regarding "high mountain disease? a. Alveolar hypoxia is the primary stimulus for pulmonary arteriolar vasoconstriction encountered in high mountain disease. b. Pulmonary hypertension of high altitude is not reversible. c. Death in high mountain disease results from acute pulmonary edema secondary to right ventricular failure. d. Only Angus breed cattle are susceptible to high mountain disease. e. Edema of the brisket ("brisket disease") is pathognomonic for high mountain disease.

Answer 26

A

Question 27

You are called out to look at a couple of calves that have been born without any complications and have done well for about a week. After a week of life they seem to get weak and lie around and be unwilling to nurse and often perish overnight. Your physical exam is somewhat unremarkable. One calf that died the previous night you preformed a necropsy on and found nothing remarkable. You recommended blood work on one of the smaller still surviving calves and found they had a remarkable rise in CK @ 250,000 as well as a Vitamin e level of 25 ( normal >150). You best explain to the rancher that this is suggestive of, and your recommendations at this time might include

Answer 27

White Muscle disease, Vitamin and possible selenium deficiency. You recommend further diagnostics including whole blood selenium levels on this calf as well as a few others in the heard and begin Vitamin E injectable therapy in those calves born already and in those cows still having to calve as well as consider nutritional supplementation after further diagnostics are evaluated

Question 28

What are the visual findings of cows with cardiac disease in ruminants

Answer 28

-Weight loss -Brisket disease -distension -bottle jaw -tachycardia -exercise intolerance -diarrhea -decline in milk production -arrhythmias -heart murmurs -cyanosis -jugular distension -rectal prolapse -bloat

Question 29

Is diarrhea a clinical sign of heart disease in ruminants?

Answer 29

yes

Question 30

What is the most common congenital defect you see in cattle/ruminants *

Answer 30

Ventricular Septal Defects

Question 31

What is the PAP of cattle with ventricular septal defects

Answer 31

PAP 114

Question 32

What is really the only use of electrocardiograms in cattle **

Answer 32

Most useful for arrhythmias -Atrial fibrillation** -AV conduction disturbance -Ventricular arrhythmias *not useful for chamber enlargement

Question 33

ECG in cattle is not diagnostic for

Answer 33

chamber enlargement

Question 34

What is the most common arrhythmia in cattle *

Answer 34

Atrial fibrillation

Question 35

What ECG lead do you use in cattle *

Answer 35

Base-Apex Lead Negative lead: right jugular furrow Positive lead: left thorax in the 5th intercostal space (level of elbow)

Question 36

Where are the ECG leads in cattle

Answer 36

Base-Apex Lead Negative lead: right jugular furrow Positive lead: left thorax in the 5th intercostal space (level of elbow)

Question 37

How can you get arrhythmias in cattle

Answer 37

GI disease equal electrolyte imbalances toxemia neoplasia

Question 38

How can GI disease lead to arrhythmias in cattle

Answer 38

1) Electrolyte imbalances 2) Toxemia 3) Neoplasia

Question 39

What should you think when you see a cattle with atrial fibrillation

Answer 39

GI issues: electrolyte imbalances *Vagas nerve vs sympathetic (pain)

Question 40

Is quinidine or digoxin indicated for the treatment of cattle arrhythmias

Answer 40

NO- treat the underlying condition -Oral and IV electrolytes -Correct the metabolic acidosis/alkalosis -Glucose

Question 41

How do you treat arrhythmias in cattle

Answer 41

Treat Underlying (likely GI) cause -Oral and IV electrolytes -Correct the metabolic acidosis/alkalosis -Glucose

Question 42

When is atrial fibrillation serious in cattle and you need to move rapidly

Answer 42

when potassium is so high that they are bradycardic

Question 43

What is most common cause of cor pulmonale in humans

Answer 43

hypoxic pulmonary hypertension

Question 44

pulmonary hypertension occurs with

Answer 44

alveolar hypoxia in conditions such as emphysema, sleep apnea, alveolar hypoxia of altitude, high altitude pulmonary hypertension

Question 45

What is the pathophysiology of BHMD ****

Answer 45

1) Alveolar hypoxia 2) Pulmonary vasoconstriction 3) Pulmonary Remodeling 4) Pulmonary Hypertension 5) Right Ventricular Hypertrophy 6) Right Ventricular Dilation 7) Right heart congestive failure

Question 46

What is the normal Pulmonary Artery pressure (PAP)

Answer 46

around 36-40mmHg

Question 47

How does increased pulmonary artery pressure occur

Answer 47

there is hypertrophy of the pulmonary artery smooth muscle

Question 48

What livestock species are hyper reactive to hypoxia

Answer 48

Bovine Porcine

Question 49

What species are hyporeactive to hypoxia

Answer 49

Ovine Caprine Canine Llama Alpaca Yak- really good

Question 50

Pulmonary artery smooth muscle responsiveness is _______________

Answer 50

genetically determined

Question 51

pitting edema

Answer 51

cardiac disease is a main cause of this where the tissue is imprintable when pressure is applied

Question 52

What would you see on necropsy of a cow with BHMD

Answer 52

1) Brisket edema/ pitting 2) SQ edema 3) Fluid and adhesions 4) Possible aneurism (pulmonary hypertension) 5) Congested liver (right sided CHF) - Nutmeg Liver 6) Enlarged Right Ventricle and Atrium 7) Cerebral Hypoxia

Question 53

What is the rule of 10 in bovine

Answer 53

there is likely 10x more fluid in the chest that you see

Question 54

How do you treat Brisket Edema

Answer 54

1) Diuretics 2) Antibiotics 3) Warming environment 4) Limited water and salt intake 5) Thoracocentessis * 6) Supportive care 7) Move to lower elevation or hyperbaric chamber 8) other: ?

Question 55

You check for pulmonary artery pressure for BHMD but what else can contribute to the development? *

Answer 55

Anything that gives you hypoxia -Fibrinous Bronchopneumonia

Question 56

T/F: Fibrinous Bronchopneumonia can cause a cow to develop BHMD

Answer 56

True- it results in hypoxia

Question 57

What plants might cause brisket disease through hypoxia

Answer 57

Locoweeds -Oxytropis spp and Astragalus) *Swainsonine

Question 58

Locoweeds -Oxytropis spp and Astragalus) can cause

Answer 58

Brisket Disease by destroying the arterioles and creating hypoxia leading to BHMD

Question 59

How do you diagnose BHMD

Answer 59

Best by pulmonary artery pressure -History/atitude -ECG -Echocardiography

Question 60

What is the normal pulmonary artery pressure in cattle

Answer 60

mean: 36mmHg

Question 61

You should cull all animals with a PAP ____________ *

Answer 61

above 50mmHg

Question 62

At this time, what is the best means of identifying cattle at risk of pulmonary hypertension and help ID those at risk for genetic carriers

Answer 62

PAP testing

Question 63

How do you do PAP testing in cattle

Answer 63

Needle into jugular into RA and RV into pulmonary artery to measure the pressure

Question 64

If you want to develop a genetic herd of cattle that are resistant to high altitudes you want to select ones with a PAP

Answer 64

of under 50mmHg (cull the others) *ideally 41mmHg

Question 65

What are the age effects of PAP testing in cattle

Answer 65

<10 months: unpredictable, used for screening only >18 months: stable and reliable Most accurate: >12 months and elevations >6500 feet

Question 66

When is PAP testing the most accurate

Answer 66

Most accurate: >12 months of age and elevations >6500 feet

Question 67

How does body condition of cattle affect PAP

Answer 67

excessive body condition increases PAP

Question 68

How does altitude affect PAP testing

Answer 68

Altitudes <5000 feet are only for screening there is 1-1.5 mmHg increase per 1000 feet elevation rise

Question 69

Why might you see hardware disease cases around parturition

Answer 69

they are pushing

Question 70

What is the pathogenesis of traumatic pericarditis

Answer 70

1) Pericardial effusion- transudate or exudate 2) Decreased venous return 3) Decreased atrial and ventricular filling 4) Decreased cardiac output

Question 71

What are the clinical signs of pericarditis in cattle

Answer 71

2-5 days post partum: decreased milk production, anorexia, odontopresis (Bruxism), respiratory grunt positive wither test CV: muffled heart sounds, tachycardia, splashing sounds, friction rub, poor U/S images

Question 72

If there is history of calving in the last month, what should you be suspicious for? **

Answer 72

Hardware disease

Question 73

What are your diagnostics for pericarditis in cattle

Answer 73

-ECG (Base Apex Leads) -Ech -Metal detector -Radiography -Laparotomy

Question 74

What are the CV clinical signs of cattle with pericarditis

Answer 74

CV: muffled heart sounds, tachycardia, splashing sounds, friction rub, poor U/S images

Question 75

What is the normal ECG for cattle with pericarditis

Answer 75

tamponade- not depolarizing well muffled because the fluid is blocking the conduction

Question 76

How do you treat Hardware disease in pericarditis

Answer 76

Pericardiocentesis- be careful for endotoxic shock Transudative: NSAIDS Exudative: Antibiotics, Pericardotomy, Digitalis + diuretics

Question 77

What should you be careful about when doing a pericardiocentesis in cattle

Answer 77

Endotoxic shock and death

Question 78

Upon cattle pericardiocentesis, you see an exudate. What should you do for treatment

Answer 78

Exudative: Antibiotics, Digitalis + diuretics

Question 79

Upon cattle pericardiocentesis, you see an transucate . What should you do for treatment

Answer 79

Transudative: NSAIDS

Question 80

Is a pericardotomy in cattle indicated

Answer 80

no- poor prognosis and very painful and expensive you cant fix it anymore because of constrictive fibrous pericarditis *Need local anesthesia, 5th rib resection, and antibiotics

Question 81

What is them most common neoplasia of cattle

Answer 81

Lymphosarcoma -Can invade the myocardium

Question 82

What valve do cattle typically get endocarditis on

Answer 82

Tricuspid valve

Question 83

What is the pathogenesis of endocarditis in cattle

Answer 83

Hemodynamics- jet/venturi effect Endothelial damage Bacteremia Agglutins Bacterial adherence

Question 84

Dogs and cats typically get endocarditis on their mitral valve, why do ruminants typically get it on their tricuspid valve *

Answer 84

Rumen leaks bacteriemia causing Liver abscesses and the bacteria goes straight to the tricuspid valve

Question 85

What is the main bacteria that causes endocarditis in cattle

Answer 85

Trueperella, others (Ecoli)

Question 86

What are the consequences of endocarditis in ruminants

Answer 86

-Thrombotic Endocarditis -Weight loss -Intermittent pyrexia -Heart murmur -Congestive heart failure -Metastatic disease -Hematology: anemia, leukocytosis, hyperproteinemia (hyperglobulinemia), monocytosis, azotemia

Question 87

How do you diagnose endocarditis in cattle

Answer 87

Clinical signs cardiac examination blood culture

Question 88

Do cows with endocarditis have heart murmurs

Answer 88

Most have no murmurs -tricuspid valve lesions often have no audible murmur

Question 89

What are the hematology changes seen in bovine endocarditis

Answer 89

Anemia Leukocytosis Hyperproteinemia (hyperglobulinemia) Monocytosis Azotemia

Question 90

How do you treat endocarditis in cattle

Answer 90

Antibiotics: Bacterial culture, prolonged treatment Possible: Digoxin (IV only in ruminants, vasodilators- hydralzine (Eq), diuretics

Question 91

How many blood cultures do you need to diagnose endocarditis in cattle

Answer 91

5 Sample when pyrexic, before antibiotic therapy, collect steriliy, *Culture aerobically and anaerobically

Question 92

If a rancher says their cow died of brisket disease, what are 4 things that might have caused this that you need to rule out

Answer 92

1) Congestive heart failure 2) Pericarditis 3) Endocarditis (tricuspid) 4) Pulmonary Hypertension

Question 93

What are differentials for murmurs in a systemically well horse

Answer 93

1) Mitral Valve Regurgitation- ruptured chrodae tendinea 2) Tricuspid valve regurgitation 3) Aortic regurgitation (insufficiency) 4) Ventricular septal defect 5) PDA 6) Aorti-cardiac fistula 7) Flow murmurs

Question 94

What are heart murmurs associated with systemic disease in horses

Answer 94

Vegetative endocarditis Pericardits

Question 95

What is the most sensitive early indicator of cardiovascular toxicity in cattle

Answer 95

Arrhythmias- atrial Fibrillation with atrial fibrillation

Question 96

Why is the heart susceptible to toxins

Answer 96

high energy demands of myocardium make it very susceptible to toxins that decrease oxygen availability (hypoxia)

Question 97

What is the best example of nitrate poisoning

Answer 97

chocolate colored mucous membranes and blood

Question 98

alters Ca2+ and Na+ transport causing an increase in intracellular Ca2+ leads to excess Ca2+ accumulation and causes myonecrosis in cattle

Answer 98

Inophores- Monesin

Question 99

gosspol causes

Answer 99

hyperkalemia (phospholipid binder) and myonecrosis of heart

Question 100

an acute or chronic degenerative process involving the ventricular myocardium

Answer 100

cardiomyopathy

Question 101

What are sudden death problems occurring in feedlots related to

Answer 101

cardiac myopathies -enlarged cardiac muscle rounded appearance

Question 102

An 8mo calf presents for acute respiratory distress, collapsed, lung auscultation is normal, flared nostrils, and lung films is normal, tachycardia, panting. CK: 45,000 overal weakness could not stand, respiratory breathing pattern: abdominal push Tropinin: mildly high What is diagnosis

Answer 102

Vitamin E/ Selenium deficiency

Question 103

Alpacas with Vitamin E/ Selenium deficiecy get

Answer 103

Diaphragmatic Paralysis- based on extreme elevated CK and clinical signs

Question 104

a fat soluble vitamin that serves as an antioxidant to protect and preserve cell membranes and proteins from oxidative damage

Answer 104

Vitamin E

Question 105

Vitamin E is synergistic with

Answer 105

Selenium

Question 106

Can you rule out Vitamin E/ Selenium deficiency if they are on green fresh forage?

Answer 106

No- it use to be the case but not anymore. it should be on your differentials

Question 107

What are clinical signs of Vitamin E/ Selenium deficiency in cattle/alpacas/ lambs

Answer 107

acute damage to muscle and nerve cells signs: stiffness, stilted gait, muscle pain, weakness, recumbency elevated muscle enzymes: CK* and AST

Question 108

Vitamin E associated diaphragm paralysis

Answer 108

neuropathy of phrenic nerve rapid (days) onset of respiratory effort -increased respiratory rate -open mouth breathing -nasal flaring -inspiratory effort -intercostal and abdominal breathing No fever no response to antibiotics *Does improve with Injectable Vitamin E

Question 109

How do you treat Vitamin E deficiency in livestock

Answer 109

supplement vitamin E -oral -injectable *can improve the phrenic nerve

Question 110

Is Vitamin E or selenium deficiency more common in Colorado

Answer 110

Vitamin E deficiency

Question 111

CK is diagnostic for Vitamin E/ Selenium deficiency in cattle. What else is

Answer 111

Arterial blood gas: hypercapnea (hypoventilation) and hypoxia CBC: normal and stress leukogram Serum chem: elevated CK* and elevated AST

Question 112

How do you prevent Vitamin E/ Selenium deficiency

Answer 112

Provide fresh pasture increase vitamin E in supplements: salts over blocks, vitamin and mineral supplements

Question 113

Vitamin E/ Selenium deficiency is seen in

Answer 113

lambs, calfs, crias

Question 114

How do inophores cause myocardial damage

Answer 114

interferes with K+ ad Ca++ transport leading to severe mitochondrial damage

Question 115

What is the prognosis of ruminant inophore use

Answer 115

animals that survive the acute exposure or have a low dose chronic exposure may show signs of congestive heart failure as well as poor weight gain and growth

Question 116

What is the treatment for fog fever

Answer 116

ionophores- decreases the production of 3-methyl-indole

Question 117

How do you differentiate Vitamin E deficiency from Vitamin D deficiency (Rickets)

Answer 117

With rickets it is hypovitaminosis D due to lack of UV activation of Vitamin D *Hypophosphatemia <5mg/dl is seen with Rickets Do a Serum Vit D analysis

Question 118

What would you see on arterial blood gas analysis of an alpaca with vitamin E def

Answer 118

hypercapnea (hypoventilation) hypoxia

Question 119

What are causes of cardiomyopathy in cattle

Answer 119

1) Ionophore toxicity 2) Plant toxins- gossypol 3) Snake venom 4) Cantharidin 5) Selenium/ Vitamin E deficiency 6) Lymphosarcoma

Question 120

How do you treat ionophore toxicity

Answer 120

activated charcoal and saline cathartic IV fluids Selenium/ Vitamin E

Question 121

What are the uses for inophores

Answer 121

-increase feed efficiency -coccidostatic -helps control bloating (bacterial selection and promotion) -Increases rumen propionate decreases acetate -Decreases production of 3-methyl-indole (tx for fog fever) -restore ruminal pH, inhibiting Strep bovis the main bacteria causing ruminal lactici acidosis

Question 122

What are the downsides to inophores

Answer 122

can cause myocardial disease causes influx of Na+ into cell followed by Ca+ resulting in mitochondrial death

Question 123

What are your differentials for cardiomyopathy in cattle

Answer 123

1) gosspol poisoning 2) vitamin E/ selenium deficiency 3) Poisoning by ionophores 4) sodium fluoro acetate, lethal rodenticide 5) plants containing cardiac glycosides 6) Staph aureus, Histophilus somni, and Mycobacterium spp can cause myocarditis with subsequent cardiomyopathy

Question 124

How do ionophores cause myofibrillar hypercontraction and degeneration

Answer 124

Rapdily bind cations and create movement across cell membranes resulting in abnormal cellular Na+ intake and loss of hydrogen ion; calcium enters the cell secondarily with a loss of membrane gradients calcium is sequestered in mitcohondria leading to failure of oxidative phosphorylation, ATP depletion, loss of Na/K pumps, and mitochondrial swelling and disruption *Increased cystolic calcium causes hypercontraction and rapid onset necrosis

Question 125

What are the target tissues of inophore toxicity

Answer 125

skeletal muscle and myocardium -pale areas and streaks in the myocardium and sub-epicardial and myocardial hemorrhages

Question 126

a 5yo hostein cow calves 4 days ago and is now not eating or drinking. Her temp is elevated and she has an ECG that shows atrial fibrillation. Based on these findings what is the preferred course of treatment for this cow?

Answer 126

Oral and IV fluids and electrolytes and antibiotics

Question 127

What makes the S4 sound

Answer 127

atrial kick- the atria are squeezing

Question 128

What makes the S3 sound

Answer 128

diastolic filling

Question 129

What covers the pulmonic valve in the horse and makes it hard to hear

Answer 129

the triceps muscle- need to push hard to hear it

Question 130

What are the 7 criteria for describing a murmur

Answer 130

1) Grade (1-6) 2) Timing (Systolic, Diastolic, Continuous) 3) Duration (Early, Holo, Pan) 4) Quality (Blowing, Course, Musical, Honking) 5) Shape (Crescendo, Descrescendo, Cresendo- Decrescendo, Band shaped) 6) Location= PMI 7) Variability (exercise, stress/ pain, excitement, sedation (alpha-2), buscopan, phenylephrine)

Question 131

systolic murmurs are heard between the

Answer 131

lub dub

Question 132

diastolic murmurs are heard between the

Answer 132

dub lub

Question 133

What does an early/early-mid murmur mean

Answer 133

shorter time closer to the S1 or S2 sound

Question 134

What does holo mean

Answer 134

the whole way between Si and S2 S1 and S2 are audible

Question 135

What does a pan- murmur mean

Answer 135

it extended over S1 and S2

Question 136

What are the different murmur quality descriptors?

Answer 136

Blowing Course Musical Honking

Question 137

A crescendo murmur means

Answer 137

it gets louder over time

Question 138

A decrescendo murmur means

Answer 138

it is getting softer over time

Question 139

a band shaped murmur means

Answer 139

it stays the same volume the whole time

Question 140

Why might there be variability in a murmur heard

Answer 140

(exercise, stress/ pain, excitement, sedation (alpha-2), buscopan, phenylephrine)

Question 141

All left sided systolic murmurs in the horse are __________________ until proven otherwise

Answer 141

mitral regurgitation

Question 142

In a horse with left sided systolic murmur, they will have

Answer 142

mitral regurgitation

Question 143

What murmur does a horse with mitral regurgitation have

Answer 143

left sided systolic murmur

Question 144

You hear a left sided systolic murmur in a horse, indicating mitral regurgitation. When do you recommend echocardiogram

Answer 144

-Pre-purchase -Grade >3-6/6 -Pansystolic -Other signs of heart disease/ failure (Exercise intolerance, increased resting heart rate/respiratory rate, atrial fibrillation)

Question 145

In a horse, is mitral valve prolapse good news when you hear a left sided systolic murmur

Answer 145

it will be mid-late systolic, bad shaped, course murmur and it is a better prognosis and good news to your client

Question 146

Yuu hear a systolic murmur of a horse over mitral valve alongside musical/hoking, high grade >3 and thrill. What likely happened

Answer 146

Ruptured Chordae Tendinea- poor prognosis

Question 147

What left sided systolic murmur is a poor prognosis in a horse

Answer 147

Chordae tendinae rupture musical/hoking, high grade >3 and thrill. What likely happened

Question 148

When might you hear an ejection/ flow murmur in a horse Grade <3

Answer 148

Alpha-2 Excitement Hemodynamic compromise change (anemia) *normal valves and disappear, good prognosis

Question 149

What is a flow/ejection murmur in a horse

Answer 149

it is a murmur that is heard due to alpha-2, excitement for hemodynamic changes like anemia. - variable Normal valves and should disappear, good prognosis

Question 150

In the horse, all right sided only systolic murmurs in the horse is

Answer 150

tricuspid regurgitation until proven otherwise

Question 151

When do you recommend doing echo on a horse with tricuspid regurgitation

Answer 151

>Grade 3/6 Pansystolic Musical *In conjunction with heart disease

Question 152

All Left sided systolic murmurs in the horse is mitral regurgitation unless it is

Answer 152

Flow ejection (variable due to drugs, excitement, or hemodynamic) Ruptured Chordae tendinae

Question 153

What horse breeds really get tricuspid regurgitation

Answer 153

Standardbreds overrepresented

Question 154

What is the most common congenital defect in the horse

Answer 154

Ventricular Septal Defect *Grade 4-6 pansystolic, band shaped course murmur with PMI over tricuspid valve with Lower grade holosystolic-pansystolic crescendo-decrescendo over left pulmonic valve (relative pulmonic stenosis)

Question 155

You hear a horse with: *Grade 4-6 pansystolic, band shaped course murmur with PMI over tricuspid valve with Lower grade holosystolic-pansystolic crescendo-decrescendo over left pulmonic valve What is the diagnosis

Answer 155

Ventricular septal defect in a horse

Question 156

If you hear a systolic right sided murmur over tricuspid in a horse, why do you need to be sure to hear one over the left pulmonic valve too **

Answer 156

Systolic murmurs over both the tricuspid and left pulmonic valve means the horse likely has ventricular septal defect *most common congenital abnormality in horse

Question 157

What murmur will you hear in a horse with aortic regurgitation (common in older horses >10yo)

Answer 157

holodiastolic decrescendo musical murmur with PMI: aortic

Question 158

What is occuring if you hear a horse with a diastolic murmur over the aorta

Answer 158

aortic regurgitation

Question 159

You have a horse with a grade 2 continuous band shaped blowing murmur with PMI over the left heart base that does not radiate over vary. What likely is happening

Answer 159

Patent Ductus Arteriosus (PDA)

Question 160

T/F: PDA are normal in neonates <96 hours old

Answer 160

true

Question 161

What murmur do you hear in horses with grade 2 continuous band shaped blowing murmur with PMI over the left heart base that does not radiate over vary.

Answer 161

PDA

Question 162

Can you ride horses with aortocardiac fistula

Answer 162

No- risk for collapse, arrhythmias, SCD

Question 163

When should you do echo on a horse with aortocardiac fistula

Answer 163

Always warrants and echo

Question 164

What murmur do you hear in a horse with a right sided continuous machinery murmur

Answer 164

Aortocardiac fistula

Question 165

What murmur do you hear in a horse with an aortocardiac fistula

Answer 165

right sided continuous machinery murmur

Question 166

What is the only possible cause of a diastolic murmur in a horse

Answer 166

aortic regurgitation

Question 167

You hear a continuous murmur in an adult horse, what could likely be happening? What if it were young horse?

Answer 167

PDA: foal Aortocardiac Fistula: adult

Question 168

What valves are most common in horses with vegetative endocarditis

Answer 168

aortic and mitral

Question 169

What are the criteria for diagnosing vegetative endocarditis in horses

Answer 169

Need two minor and one major to diagnose it or you really just get the vibe Major criteria: microbial growth on blood culture, echo abnormalities of valves, new or different murmur Minor criteria: predisposing factors, fever, thromboembolic disease, clinpath evidence of bacterial infection, immunologic disease

Question 170

How do you treat vegetative endocarditis in horse

Answer 170

Antibiotics: -cidal, prolonged IV, ideally choice made based on positive blood culture Antithrombotics: Aspiring, clopidogrel, enoxaparin Prognosis is generally poor for this disease

Question 171

How might horses get vegetative endocarditis iatrogenically

Answer 171

jugular catheter site infection causes the infection of the

Question 172

Eastern tent caterpillars are associated with

Answer 172

pericarditis

Question 173

What causes Mare Reproductive loss syndrome

Answer 173

eastern tent caterpillars -> pericarditis

Question 174

How do you treat pericarditis in horse

Answer 174

Drain, if tamponade suspected Lavage Antimicrobials

Question 175

Why might a horse get myocarditis

Answer 175

1) Monensin toxicity 2) Strongylus vulgaris 3) Rattle snakes 4) Cantharidin (blister beetles)

Question 176

What parasite can cause myocarditis in horse

Answer 176

Strongylus vulgaris

Question 177

When horses get myocarditis from either monensin toxicity, strongylus vulgaris, rattle snakes, or cantharidin. What is the result

Answer 177

fibrosis and development of ventricular arrhythmias

Question 178

How do you diagnose myocarditis in horses

Answer 178

echo appearance cTnl (cardiac troponin) history

Question 179

What side of the heart do you tap for a horse with pericarditis

Answer 179

left side

Question 180

How do you treat congestive heart failure in horses

Answer 180

Furosemide Antithrombotics Digoxin *Prognosis is generally poor, unless underlying cause can be addressed

Question 181

What are the clinical signs of equine congestive heart failure

Answer 181

tachycardia pulmonary edema plueural effusion jugular distension/ pulsation hepatic congestion atrial fibrillation ascites ventral edema

Question 182

What ECG set up do you use in a horse

Answer 182

Base-Apex ECG- read off of lead II

Question 183

What does a horse ECG look like on lead II

Answer 183

P wave: can sometimes be two waves, wide QRS: Negative R wave T: positive T wave

Question 184

What are exercising ECGs used for in horses

Answer 184

-Assess fitness -Determine if arrhythmias are overdriven with exercise -Determine if arrhythmias are overdriven with exercise -Determine if arrhythmias degrade with exercise -Assess cardiac compensation for disease -Safety assessment *Must be as rigorous as the work required of horse will be

Question 185

Exercise ECGs in horses need to be

Answer 185

as rigorous as the work required of horse will be

Question 186

What is normal heart rate for a horse

Answer 186

28-48bpm (mini horses run higher into the 50s) foals: 80-120

Question 187

What is a normal heart rate for a foal

Answer 187

80-120 (nx for adult is 28-48bpm)

Question 188

What arrhythmias are common in horses

Answer 188

Atrial fibrillation Atrial premature contraction ventricular premature contraction 2nd degree AV block

Question 189

What AV block is commonly seen in horses*

Answer 189

Second Degree AV block- mostly a benign result of high vagal tone *should ablate with exercise or administration of atropine

Question 190

Second Degree AV block in horses is extremely common. What is significant about it

Answer 190

almost always a benign result of high vagal tone. Should ablate with exercise or administration of atropine Not always benging if it is high degree (>2 consecutive block beats)

Question 191

2nd degree AV block in horses is typically benign but when is it not

Answer 191

When there is high degree- presence of >2 consecutive blocked beats Block does not resolve with exercise

Question 192

What are the recommendations to horses with second degree AV block

Answer 192

High Degree that disappears with exercise: only be ridden or driven by an informed adult high degree that disappears with exercise or atropine should be rested and re-evaluated but considered less safe to ride or drive *Horses with symptomatic bradyarrhythmias generally have a poor prognosis and are not safe to ride

Question 193

For a 2nd degree AV block to be advanced/ high grade there needs to be (in horse)

Answer 193

greater than 2 consecutive blocked beats

Question 194

How do you manage a horse with advanced 2nd degree AV block

Answer 194

pacemaker implantation

Question 195

What is the most important arrhythmia in horses leading to poor performance

Answer 195

Atrial fibrillation

Question 196

What are the hallmarks for atrial fibrillation in horse

Answer 196

f waves No P waves Irregular R-R intervals

Question 197

Atrial fibrillation in horses might be due to

Answer 197

1) Genetics (Standardbreds) 2) Age- older 3) Atrial Dilation (ex: mitral valve regurgitation) 4) Strenuous exercise 5) Concurrent cardiac disease 6) APCs

Question 198

How do you treat atrial fibrillation in a horse

Answer 198

Convert to sinus rhythm 1) Quinidine Conversion (Class 1a Na+ Channel Blocker) -expensive 2) Transvenous Electrical Conversion (TVEC)

Question 199

When should you consider converting a horse in atrial fibrillation

Answer 199

1) No structural cardiac disease 2) Horses has been in atrial fibrillation <4months 3) Maximum atheletic capacity 4) Rode by a child rider 5) If this is first occurence

Question 200

What should you do if the clients opt not to convert atrial fibrillation in horse

Answer 200

Horse can be used if 1) Used by informed consenting adult 2) HR <220bpm sustained during maximal exercise 3) No concurrent ventricular arrhythmias during exercise determined

Question 201

What do you see on ECG of a horse with atrial premature complexes

Answer 201

Irregular RR interval with normal QRS morphology P waves occasionally evident

Question 202

What causes atrial premature complexes in horses

Answer 202

changes to autonomic tone hypokalemia drugs (catecholamines, anesthetics) systemic disease-colic, fever, hemorrhage structural cardiac disease

Question 203

What should you tell the client if their horse has atrial premature complexes

Answer 203

APCs can be overdriven with exercise or are occasional during exercise *possibility for degrading into Afibrillaton is likely higher than those without APCS

Question 204

What do ventricular premature complexes look like in horses

Answer 204

Ectopic focis originating in the ventricles generating aberrant ventricular depolarization Early beat, no p wave Abnormal T wave repolarization QRS does not match