Cardiac disease

Question 1

Normal heart function

Answer 1

The amount of blood entering the heart (pre-load) should equal the amount of blood exiting the heart (after-load)
If more blood is trying to enter the heart than is leaving it, that could cause a damming effect and higher pressure “upstream”
Each contraction of the heart should result in the maximum volume of blood being pumped out. If there is insufficient blood being pumped out of the heart; this may result in lack of tissue perfusion. Lack of perfusion means tissues may not receive adequate oxygen and nutrients and removal of waste products will be impaired.

Question 2

Effusion

Answer 2

Fluid in 3rd space

Question 3

Pulmonary edema

Answer 3

Fluid accumulate in alveoli. Prevents oxygen uptake

Question 4

Pleural effusion

Answer 4

• fluid around the lungs; prevents filling with air

Question 5

Abdominal effusion

Answer 5

Fluid in the abdomen

Question 6

Ascites

Answer 6

Clear fluid in the abdomen

Question 7

Primary cardiac disease

Answer 7

When something goes wrong with the heart itself
Congenital or inherited, traumatic, degenerative

Question 8

Secondary cardiac disease

Answer 8

When something goes wrong elsewhere in the body that affects the heart, or puts additional strain on the heart
Systemic disease, infection, toxicity, metabolic, secondary to lung disease

Question 9

Causes of secondary heart disease

Answer 9

Systemic disease
Hyperthyroidism, renal disease, neoplasia, pulmonary disease
Infection
Periodontal disease, neonatal septicemia, heartworm, hardware disease
Toxicity
Digitalis, arsenic, snakebites
Metabolic
Copper and selenium deficiencies

Question 10

Prognosis of cardiac disease

Answer 10

Depends on the cause
Rate of progression of disease is variable
Depends on the severity of disease
Prognosis decreases once c/s are present
Secondary damage to other organs/tissues
Left untreated it will eventually progress to heart failure

Question 11

Top 4 cardiac diseases

Answer 11

Mitral valve insufficiency (dogs/horses)
Hypertrophic cardiomyopathy (cats)
Dilated cardiomyopathy (dogs)
Endocarditis (cattle)

Question 12

Who is most susceptible to cardiac disease

Answer 12

Old dogs
Main coons
Cavalier king charles
Heartworm

Question 13

Typical presenting complaint of cardiac disease

Answer 13

Syncope (fainting spells) looks similar to a seizure
Weakness
Open mouth breathing in cats
Coughing
Exercise intolerance
LA: decreased production, weight loss, fever
Animals are often asymptomatic at the time of diagnosis, or only subtle signs are present

Question 14

Tachycardia

Answer 14

Increased HR

Question 15

Bradycardia

Answer 15

Decreased HR

Question 16

Arrhythmia

Answer 16

irregular heartbeat due to problems with the sinus node or conductivity

Question 17

Murmurs are described by

Answer 17

“Whooshing” sound= turbulence
Describing murmurs
How loud?
Grades 1-6
Where are they the loudest (left or right side, same, which rib space)
Associated with systolic or diastolic
Has it changed over time

Question 18

Diagnostics used for heart disease

Answer 18

Echocardiogram (echo)
Ultrasound of the heart- most accurate
Radiographs
Electrocardiogram (ECG=EKG)
Blood pressure measurement

Question 19

Taurine deficiency can cause

Answer 19

Cats can get DCM if eating a taurine deficient diet
Dogs can get taurine from other amino acids
Except for certain lineages AM Cocker spaniels
Possibly golden retrievers

Question 20

Source of taurine

Answer 20

Insects
Raw Meat- birds, seafood
Commercial cat food (250-500 mg/day)

Question 21

DCM pathology

Answer 21

Acquired
Pathology
Problem with the cardiac muscles; weakness over time
Heart muscles becomes distended, flabby, weak
Left side of the heart usually affected first; followed by right side
Outline of the heart becomes larger and rounded and the ventricles are enlarged
As the muscles continues to stretch
The conductive fibers become spread out, and mya lose their ability to coordinate muscle contraction
Cardiac vessels become spread out and areas od the heart may have less perfusion
Pump becomes less effective (decreased stroke volume
Decreased peripheral perfusion

Question 22

Clinical signs of DCM

Answer 22

Weakness, lethargy, exercise intolerance, cough, syncope
Some dogs do not show signs of clinical disease until they are already into heart failure
Sudden collapse

Question 23

Treatment for DCM

Answer 23

Goals of treatment are
Increase strength of heart muscle- to help the heart get stronger and increase cardiac output
Decreased heart rate-prevent heart from tiring out

Question 24

Prognosis for DCM

Answer 24

Progressive
Cannot reverse heart muscle damage
May die from lack of tissue perfusion or the heart muscle gives out
Or, the disease will eventually progress to congestive heart failure with pulmonary effusion
Death can be sudden

Question 25

Non-hereditary DCM can be caused by

Answer 25

2018–FDA Investigation began because DCM was being diagnosed in breeds not typically predisposed to the condition Sometimes multiple dogs within the same household Pathophysiology not yet completely understood Associated with diets containing legumes or potatoes as main ingredients (grain free diets) Believed to be linked to taurine

Question 26

Hypertrophic cardiomyopathy is caused by

Answer 26

Primary HCM- inherited in cats Myosin mutation Secondary to hyperthyroidism in cats Secondary to mitral valve disease in dogs Can be secondary to any disease that makes the heart work harder The heart is a muscle; muscles grow when they are exercised

Question 27

Sequelae is

Answer 27

Thickening of the LV muscle Decreased filling space Less blood pushed out per pump (decreased cardiac output) AND Back-up of blood to atria Back up of blood to veins Heart muscle outgrows its own blood supply Increased risk of clot formation (cats) Because less blood exits the heart each time it pumps, the heart has to beat faster…..once this disease starts, it is chronic, progressive, and makes itself worse over time

Question 28

Presenting and clinical signs of hypertrophic cardiomyopathy

Answer 28

Exercise intolerance, syncope Swollen (belly,limbs) ADR= “ain't doing right” Hind end weak or paralyzed Open mouth breathing, struggling to breathe Cyanosis Sudden collapse IF THE BOTTOM THREE ARE SHOWN IT IS AN EMERGENCY

Question 29

Goals of treatment for hypertrophic cardiomyopathy

Answer 29

Treat the underlying condition Decrease the workload on the heart Keep blood pressure within normal limits Prevent thromboemboli

Question 30

Death by HCM is caused by

Answer 30

Pleural effusion and pulmonary edema inhibit gas exchange Heart outgrows its own blood supply Clots block blood flow back to heart or to the brain Lack of tissue perfusion

Question 31

Endocardiosis

Answer 31

degenerative thickening Dogs, horses

Question 32

Endocarditis

Answer 32

Inflammatory; may or may not be infectious Cattle

Question 33

Bacterial endocarditis in cattle primary causes

Answer 33

A secondary cardiac condition Primary causes include Metritis (inflammation of the uterus) Mastitis Foot or liver abscesses Septic arthritis Traumatic reticular peritonitis Long term indwelling catheter

Question 34

Bacterial endocarditis in cattle clinical signs and PE findings

Answer 34

Weight loss Anorexia Heart murmur Decreased production Fever Sudden death

Question 35

Mitral valve insufficiency/regurgitation is common in

Answer 35

Mitral valve endocardiosis Endocardiosis = degenerative Dogs and horses Older animals Dogs: smaller breeds, males, overrepresented

Question 36

Mitral valve regurgitation is

Answer 36

Backflow/leaking of blood into LA Turbulence = murmur Heart pumps harder → secondary thickening of heart muscle

Question 37

Heart failure is characterized by

Answer 37

When the heart can no longer pump to meet the demands of the tissues Heart can’t pump enough blood, so there is a backup that occurs = Congestive HF Many underlying causes of HF

Question 38

Subclinical HF is

Answer 38

Aka asymptomatic HF Heart does not pump effectively No clinical signs Patient may not be aware of changes in body Compensatory mechanisms help maintain BP Blood vessels constrict Body retains water Keeps tissues perfused Start treatment when heart enlargement is detectable on radiographs - FOR LIFE

Question 39

Clinical HF is

Answer 39

Patient has clinical signs Clinical signs appear because compensation is no longer enough to maintain normal blood flow through the heart to the rest of the body Additional medications indicated at this point if owner is willing

Question 40

Pathology of clinical HF

Answer 40

Decreased output from the heart This caused decreased perfusion of tissues Clinical signs Syncope Weakness, exercise intolerance May lead to tissue/organ damage (especially kidneys) Back up BEFORE the heart Be able to explain what can happen when there is increased preload

Question 41

What happens in LEFT sided congestive HF

Answer 41

Pulmonary edema in left sided HF Fluid in alveoli Clinical signs are related to respiration Open mouth breathing Struggling to breathe Cyanosis Shallow, rapid respiration

Question 42

What happens in RIGHT sided congestive HF

Answer 42

Liver in RSHF → may develop liver failure Abdominal distension due to ascites Note that the animal is otherwise cachexic (can see the ribs and dorsal column)

Question 43

Treating HF

Answer 43

Rest, restricted activity/excitement Reduce salt intake Vasodilators- Dilate blood vessels (decrease BP) Diuretics- to increase urination (decrease BP) Drugs to slow down heart to prevent arrhythmias Preventing thromboemboli

Question 44

Prognosis of HF

Answer 44

Guarded - ALWAYS progressive Will eventually lead to death d/t: Pulmonary edema +/- pleural effusion Output failure Arrhythmia may or may not be present Cardiac infarct