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Flashcards in SA Respiratory and CV Deck (442)
1

What is the function of a cough?

Removes material from airways:
Assists mucociliary clearance
Expels inhaled material
Protects against inhaling particles/inhalants

2

Where are mechanoreceptors located?
What about chemoreceptors?

Mechanoreceptors: larger airways
Chemoreceptors: medium airways

3

Where are cough receptors most numerous?

Larynx > trachea > bifurcation > bronchi

4

Give some common differential diagnoses of coughing

Compression of mainstem lobar bronchi (eg left atrial enlargement)
Stimulation of cough receptors (eg tracheal/laryngeal/bronchial disorders)
Excessive mucous/fluid/inflammation (eg pulmonary oedema, pneumonia, bronchopneumonia)

5

Chronic bronchitis is mainly seen in which kinds of dogs?

Small breed dogs

6

How should a cat's thorax feel when compressed?

Springy

7

What might you see on a radiograph of a dog with chronic bronchitis?

'Tram lines'
Rings- thickened bronchial walls

8

Give some characteristic changes to the bronchi caused by chronic bronchitis

Excessive mucous production
Damage to cilia
Increased goblet cell numbers
Hyperplasia of submucosal glands
Loss of ciliated epithelium
Squamous metaplasia of mucosa
Secondary infections are common

9

How does a dog with chronic bronchitis present?

Chronic cough with attempts at production
Worse on excitement

10

Can you cure chronic bronchitis?

No, therapeutic goal is to manage it with bronchodilators and steroids (anti-inflammatory glucocorticoids). Avoid systemic steroids to prevent weight gain

11

How can you investigate a suspected chronic bronchitis case?

Thoracic radiographs
Haematology
Bronchoscopy
Bronchoalveolar lavage to obtain samples for cytology/bacteriology/parasitology

12

When doing a bronchoalveolar lavage in a dog, how much saline should you use?

1/2ml per kg bodyweight

13

If you see worms on a tracheobronchoscopy what are they likely to be?

Crenosoma vulpis (fox lungworm)

14

When you do a bronchoalveolar lavage, how much fluid should you expect to aspirate back?

50%

15

What cells are normal to see on a BAL fluid analysis?

Goblet cells
Ciliated columnar epithelial cells (CCECs)

16

If you see macrophages containing bacteria on a BAL fluid analysis, what does this tell you?

There is an active infection

17

What are the normal values in BAL fluid analysis for:
WBC
Macrophages
Neutrophils
Lymphocytes
Eosinophils

WBC: <5x10^9/l
Macrophages: 70%
Neutrophils: 20%
Lymphocytes: 10%
Eosinophils: <20-25%

18

What would you see on a cytology of BAL fluid in chronic bronchitis?

Increased mucous, neutrophils, macrophages
Possibly squamous metaplasia of normal ciliated columnar epithelial cells
Presence of bacteria/particulate matter

19

If you do a BAL in a dog with chronic bronchitis and you see Simonsiella, what does this mean?

Oral contamination

20

How can you manage chronic bronchitis (non-medically)?

Weight control
Harness rather than collar
Avoid irritants/smoking environment
Mucous is easier to shift if hydrated-avoid dry environments

21

Give the functions of bronchodilators

Reduce spasm of lower airways
Reduce intra-thoracic pressures
Reduce tendency of larger airways to collapse
Improve diaphragmatic function
Improves muco-ciliary clearance
Inhibit mast cell degranulation (reduced release of mediators of bronchoconstriction)
Prevent microvascular leakage

22

Give some functions of glucocorticoids

Anti-inflammatory
Broncho-dilatory
Inhibit prostaglandin synthesis
Potentiate beta-2 adrenergic activity -> bronchodilation
Reverse increased vascular permeability
Alter macrophage function
Modulate the immune system

23

Would you give antibiotics when treating chronic bronchitis?

Most chronic bronchitis cases are not caused by bacteria
Only give antibiotics if secondary infection is possible, or if culture and sensitivity results are positive, or if intracellular bacteria are seen on BALF cytology

24

If you decide to use antibiotics when treating respiratory tract infections, what criteria should it fit?

Needs to concentrate in the lung
Needs to be effective against resp. pathogens
Should be bacteriocidal
Need to treat for 3 weeks minimum

25

Give some examples of antibiotics used for respiratory infections

Clavulonate potentiated amoxicillin (broad-spectrum)
Cephalexin (mainly gram -ves)
TMP sulphonamides (broad-spectrum)
Fluoroquinalones (broad-spectrum)
Clindamycin (mainly gram +ves and anaerobes)
Doxycycline (Mycoplasma or Bordatella)
Metronidazole (anaerobic, some bronchopneumonias)

26

Eosinophilic bronchopneumopathy (EBP) usually affects which kinds of dogs?
What is thought to be the cause?

Young dogs, large breeds
Hypersensitivity to inhaled allergens

27

What would you see on a bronchoscopy of a dog with eosinophilic bronchopneumopathy?
What would you see on a BALF cytology?

Copious amounts of yellow-green mucous

Lots of eosinophils (>25%)

28

How do you treat eosinophilic bronchopneumopathy?

Prednisalone (2mg/kg/alternate days) (immunosuppressive)

29

Why do cats have an expiratory dyspnoea with feline asthma?

The bronchioles are more constricted during expiration

30

How does the chest of a cat with feline asthma differ on a radiograph?
What should you also look out for?

Chest is more concave
Look out for fractured ribs (cats can be so dyspnoeic that they fracture ribs)

31

How can you care for a dyspnoeic cat with feline asthma?

Minimise stress
Provide humidified oxygen
Give IV steroids
Bronchodilators (eg terbutaline)
Consider MDI (metered-dose inhalers) administration of bronchodilators (salbutamol, fluticasone)
Severe life-threatening distress: adrenaline
Chronic cases: prednisolone

32

What kind of coughing is seen with bronchial foreign bodies?

Sudden onset
If long-standing, may be halitosis

33

What is orthopnoea?

Extreme form of dyspnoea
Animals have to sit up/stand to breathe and adopt an air-hungry position with abducted elbows

34

Give some differential diagnoses of inspiratory dyspnoea

Laryngeal neoplasia/paralysis
Tracheal mass/stenosis

35

Give some differential diagnoses of expiratory dyspnoea

Feline asthma
Dynamic airway collapse (small airway collapse; only hear wheezing with stethoscope)

36

Give some differential diagnoses of both inspiratory and expiratory dyspnoea

Pulmonary parenchymal disease (eg pneumonia)
Pleural effusions
Pneumothorax
Pulmonary thromboembolism

37

What kind of disease causes restrictive dyspnoea

Pulmonary and pleural disease

38

Does restrictive dyspnoea occur on inspiration or expiration?

Both

39

What kind of obstruction is present with obstructive dyspnoea on inspiration and expiration?

Inspiration: upper airway obstruction
Expiration: bronchial narrowing

40

When giving oxygen therapy, what should the value of inspired O2 be?
Why should you avoid 100% oxygen for more than a short time?

30-50%
Oxygen toxicity
Oxygen must be humidified

41

Pneumonia in small animals is usually associated with what?

Broncho-pneumonia

42

Give some causes of aspiration pneumonia

Megaoesophagus
Laryngeal paralysis
After tie-back surgery

43

Regarding pneumonia, what does a ventral distribution (on radiograph) suggest?

Airway disease or aspiration as the initiating factor

44

Regarding pneumonia, what does caudodorsal lung involvement (on radiograph) suggest?

Haematogenous spread

45

What is pneumocystis carinii?
What does is respond to?

A yeast-like fungus
Causes pneumonia
Cavalier King Charles puppies have immunoglobulin deficiency and may present with dyspnoea due to pneumocystis carinii pneumonia
Only responds to TMP sulphonamides

46

Where is angiostrongylus vasorum found in the dog?

Pulmonary vessels
(french heartworm)

47

A 'goose honk' cough is associated with what?

Tracheal collapse

48

When radiographing a mass on the right lung lobe, which view should you use?

Left lateral

49

When is it safe to do a lung mass aspirate?

If you're not going through air-filled lung
If the mass is next to the chest wall (or risk pneumothorax)
Can be ultrasound-guided

50

Idiopathic pulmonary fibrosis typically affects which dog breeds?

Terriers, especially west highland white terriers

51

Describe the presentation of idiopathic pulmonary fibrosis

Slow, insidious progression
Inspiratory and expiratory dyspnoea, rapid shallow breathing, can develop rectus abdominis hypertrophy and become cyanotic on minimal exertion
Characteristic 'crackles' (inspiratory) on lungfield auscultation (dynamic airway collapse)
Become severely disabled
Active inflammation on CT scan

52

How do you treat idiopathic pulmonary fibrosis?

Symptomatic support-nothing proven to be effective
General management: restrict exercise and excitement
Bronchodilators? (esp if dynamic airway collapse or concurrent chronic bronchitis)
Anti-fibrotics? (eg colchicine)
Steroids? (prednisolone)
Home O2 delivery? (when distressed)

53

Describe paraquat poisoning

Weedkiller, severe pneumotoxin
Severe dyspnoea
Initial alveolitis progresses to severe pulmonary fibrosis
Very poor prognosis-PTS

54

Is pulmonary thromboembolism usually primary or secondary?

Secondary to underlying systemic disease eg IMHA, DIC, PLN, Cushings, pancreatitis, sepsis (not usually cardiac dz)
(losing protein -> lose clotting factor -> clots more likely)

55

When should you suspect pulmonary thromboembolism?

Sudden onset dyspnoea

56

How can you confirm pulmonary thromboembolism?

Blood gas analysis
Coagulation screen (including D-dimers)

57

How do you treat pulmonary thromboembolism?

O2 supplementation
Sedation/anxiolytics
Treat underlying disease (eg DIC)
Anticoagulant treatment to prevent further episodes (eg heparin)
Anti-platelet medication (eg clopidogrel)

58

What is ARDS (acute respiratory distress syndrome)? Give some initiating factors

Non-cardiogenic pulmonary oedema
Respiratory distress with alveolar infiltrates on radiographs
Pneumonia, electrocution, smoke inhalation, near drowning, trauma, sepsis, DIC

59

Should you be concerned if you see pleural plaques on a radiograph?
What do they look like?

No-they are incidental findings
Small, white, calcified, dense, 1-2mm

60

What is a holter monitor?

Records ECG for 24 hours

61

Give some cardiac causes of episodic weakness/syncope

Compromised cardiac output
-Congenital heart disease (esp aortic stenosis, patent ductus arteriosis)
-Dilated cardiomyopathy
-Hypertrophic cardiomyopathy (cats)
-Cardiac tamponade
-Cardiac neoplasia

Cardiac arrhythmias
-Tachyarrhythmia
-Bradyarrhythmia

62

Give some causes of tachyarrhythmia

Atrial fibrillation
Supraventricular/atrial premature complexes
Ventricular premature complexes
Supraventricular tachycardia
Ventricular tachycardia

63

How would atrial fibrillation appear on an ECG?

No p waves
Irregularly irregular ventricular rhythm
Normal narrow QRS complexes (as arrhythmia is originating above AV node)

64

What is atrial fibrillation associated with in small animals?

Cardiac disease-atrial stretch

65

How do you treat atrial fibrillation?

Treat underlying cardiac disease and aim to control ventricular response to the AF
To control, you can use digoxin, beta blockers (not if underlying CHF), Ca2+ channel blockers

66

What is digoxin?

Weak positive inotrope (increases heart contractility)
Negative chronotope (slows HR)
Enhances vagal tone (slows down no of waves of depolarisation that reach the ventricles)
Indicated for:
-Atrial fibrillation
-Other supraventricular arrhythmias
-Sinus tachycardia
-Poor systolic function

67

Why should you be careful when increasing the dose of Digoxin when treating atrial fibrillation?

Toxicity; need to add Diltiazem (calcium channel blocker)

68

When treating atrial fibrillation with Digoxin, what should the desired digoxin level be after 5-7 days?

0.5-0.9 ng/ml

69

What is Diltiazem?

Calcium channel blocker used to treat atrial fibrillation
Negative inotrope (reduces contractility but this is rarely a problem)
Vasodilator (as affects vascular smooth muscle as well as myocardium)

70

When Digoxin and Diltiazem are used together to treat atrial fibrillation, which drug starts to work first?

Diltiazem
Digoxin kicks in after a week

71

Should you ever use beta blockers to treat uncontrolled CHF?

NO

72

Describe emergency treatment of supraventricular tachycardia

Vagal manoeuvres (apply gentle pressure to eyeballs, carotid sinus massage under jaw)
IV Esmolol (beta blocker)
IV Verapamil (Ca2+ channel blocker)

73

How would conduction via the accessory pathway appear on an ECG?

Short P-R interval

74

'Delta' waves can occur in animals with which heart condition?

Supraventricular tachycardia caused by Wolff-Parkinson-White syndrome

75

Give some underlying causes of ventricular ectopic focuses

Underlying cardiac disease; CHF (ischaemia, myocardial hypoxia etc)
Acidosis
Hypokalaemia
Catecholamines (eg stress, pain etc)
Abdominal disease (GDV, splenic lesions, sepsis, perforated gastric ulcer, pancreatitis etc)
Thoracic trauma (myocardial contusions)

76

When should you treat ventricular ectopics?

If it is haemodynamically significant
If HR is very fast/there is close coupling/'R on T'
If multifocal
Monitor with halter

77

What are the 4 classes of anti-arrhythmic drugs?

Class 1: sodium channel blockers (slows uptake of action potential)
Class 2: beta-blockers
Class 3: potassium channel blockers (delays repolarisation/lengthens action potential duration)
Class 4: calcium channel blockers (act on SAN or AVN) (treat supra-ventricular arrhythmias)

78

How would you treat a ventricular tachyarrhythmia?

Lidocaine (IV boluses; sodium channel blocker)
Sotalol (oral beta blocker)
Mexilitine (oral; sodium channel blocker)
Amiodarone (oral; potassium channel blocker)

79

How would you identify atrial standstill on an ecg?

No p waves
T waves are spiky and symmetrical
Normal QRS complexes

80

How would you identify a 2nd degree block on an ecg?

Non-conducting P wave, 3-4 normal QRS, non-conducting P wave

81

How would you identify a 3rd degree block on an ecg?
How would you treat?

Atria and ventricles are depolarising independently
P-P intervals are regular
QRS complexes have a regular R-R interval
P-R interval is varied
(Impulse generated in the SAN does not propagate to the ventricles)
Tx: Pacemaker

82

How would you identify a 1st degree block on an ecg?

Long P-R interval
(Impulse travelling from atria to ventricles is delayed and travels slower than normal)

83

How would you treat bradyarrhythmias?

Exclude/treat underlying disorders (eg hyperkalaemia, hypothyroidism etc)
Vagally mediated? Try response to anticholinergics: atropine response test (expect >50% increase in HR after 30-40 mins)
Life threatening: b-agonist eg isoproteranol or b2-agonist eg terbutaline
Oral meds: anticholinergics (eg atropine, propantheline), beta sympathomimetics (terbutaline), xanthine derivatives (eg theophyline)

84

Why would we measure blood pressure?

Anaesthetic monitoring
Assessing severity of heart disease
Identification of systemic hypertension
Assessing response to drugs (eg vasodilators)

85

How do we measure blood pressure?

Direct method (more likely in anaesthetised patients)
Indirect methods (Doppler, oscillometric technique)

86

What is meant by systemic hypertension?

Blood pressure above normal for the species/breed

87

What is the normal blood pressure range for dogs?

(S/D) 133/75 mmHg
Sight hounds have higher blood pressure than other breeds (150/87 mmHg)

88

What is the normal blood pressure range for cats?

(S/D) 125/80 mmHg

89

What are the definitions of systemic hypertension for systolic and diastolic pressure?

Systolic: >160/175/180 mmHg
Diastolic: >95-100 mmHg
(eg 175/100 mmHg)

90

Give some disease associated with secondary systemic hypertension?

Chronic renal disease
Hyperthyroidism (cats)
Hyperadrenocorticism
Diabetes mellitus
Liver diseases
Hypothyroidism
Acromegaly (excess GH)
Obesity
CNS disease
Chronic anaemia (cats)
Phaeochromocytoma (adrenal gland tumour)
Hyperaldosteronism

91

Give some consequences of systemic hypertension

Ocular (retinal haemorrhage, hyphaema-pooled blood in anterior chamber of eye, retinal detachment, blindness)
CNS (seizures, dull and depressed, bad-tempered)
Renal (failure, proteinuria etc)
Cardiac (pressure overload -> concentric left ventricular hypertrophy, heart murmurs)

92

What is the difference between eccentric and concentric ventricular hypertrophy?

Eccentric: volume overload. Wall thickness increases in proportion to the increase in chamber radius

Concentric: chronic pressure overload. Wall thickness increases but the chamber radius may not change, ventricle becomes stiff

93

What should you do after diagnosing systemic hypertension?

Check for end-organ damage (examine retinas, history and neuro exam, check urine SG and protein:creatinine ratio, ECG)
Search for an underlying cause as primary hypertension is rare in cats and dogs

94

Which drug can you use to treat systemic hypertension?
What doses would you use for dogs and cats?

Amlodipine (calcium channel antagonist with only vascular effects)
Cats: start at 1/4 of 5mg tablet, SID
Dogs: start at 0.05-0.1mg/kg SID or BID
Check BP after 1 week, increase dose if required

95

When treating systemic hypertension, what can you use as well as Amlodipine to protect the kidneys?

Ace inhibitors
(reduce glomerular capillary pressure)

96

What is the difference between a thrombus and embolus?

Thrombus= initial clot
Embolus= clot which breaks off and travels down blood vessels

97

Why may a blood clot form?

Circulatory stasis
Hypercoagulable state
Endothelial injury
(Known as Virchow's triad)

98

Where do feline arterial thrombus' usually form?

Left atrium

99

What is FATE in cats?
Describe the physiology

Feline arterial thrombo-embolism
Thrombus forms, usually in left atrium, due to stasis of flow within the heart (any feline cardiomyopathy)
Embolisms may be to any region-often distal aorta (aortic trifurcation)
Severe clinical signs, pain etc
Emergency presentation

100

What is the major clinical sign of a cat presenting with FATE?

Loss of use of HLs
(Marked pain, pale nail beds)

101

What would be your first priority when seeing a cat with FATE?

Adequate analgesia

102

How do you treat FATE?

Priority: adequate analgesia and anxiolytic eg methadone, aspirin
Consider 'clot busting' drugs eg tissue plasminogen activator (tPA) if <6-12 hours of event
Stabilise underlying heart failure if present
Inhibit further platelet aggregation and activation eg aspirin, heparin
Prevent collateral vasoconstriction caused by thromboxane, serotonin etc (aspirin)
Grave prognosis, 50% survival rate

103

How can you prevent FATE in at-risk cats?

Low-dose aspirin (1/4 of 75mg aspirin every 3 days)
Clopidogrel (anti-platelet; inhibits blood clots) (better than aspirin)
Low molecular weight heparin
Treat cardiac disease as appropriate

104

Which dog breed may be pre-disposed to arterial thrombo-embolism?

Cavaliers

105

What is canine arterial thrombo-embolism associated with?

Rarely heart disease
More commonly associated with an endocrinopathy eg cushings, hypothyroidism

106

How would you identify canine thrombo-embolism?

Dogs present with HL weakness or pain, worse with exercise, sometimes only single limb
Pale/pulseless/cold compared with non-affected limb

107

Give some causes of pulmonary hypertension

Pulmonary vascular changes (eg retained foetal vasculature) -> pulmonary hypertension -> right to left shunting across congenital heart defects
Heart worm
Pulmonary thromboembolism
Left-sided heart failure
Primary severe respiratory conditions

108

How can you diagnose pulmonary hypertension?

Clinical exam: loud S2, loud TR murmur (tricuspid regurgitation)
Radiographs: dilated, tortuous or pruned pulmonary arteries
Doppler echo: dilated and hypertrophic RV, dilated pulmonary trunk, high velocity TR, PR jets

109

How do you treat pulmonary hypertension?

Treat underlying disease
Pimobendan?
Sildenafil (Viagra)

110

How do you diagnose pulmonary thrombo-embolism in dogs?

Arterial blood gas analysis: large alveolar to arterial gradient (A-a) showing significant ventilation:perfusion mismatch
Identify clot breakdown products: FDPs, D-dimers

111

Give some clinical signs of heartworm

Weight loss, fatigue, cough, dyspnoea

112

Which side of the heart are canine heartworms found?

Right

113

How do you diagnose canine heartworm?

Direct smear
Microfilaria concentration tests eg Modified Knott's test
Heartworm antigen tests (only detects females)
Antibody test

114

Which drugs will prevent canine heartworm?

Selamectin (Stronghold), monthly topical
Milbemycin (Milbemax) (with praziquantel), po monthly
Moxidectin (Advocate) (with imidacloprid), monthly topical

115

What are Wolbachia?

Obligate, intracellular, gram negative, endo-symbiotic bacteria
Found in uterus of female Dirofilaria immitis
Treat with doxycycline prior to melarsamine

116

What adulticide would you use to treat Dirofilaria?

Melarsomine Dihydrochloride

117

What is angiostrongylus vasorum?

'French heart worm'
Adults are 2cm long
Metastrongyle parasite of dogs and foxes
Slugs and snails=intermediate host

118

What are the clinical signs of angiostrongylus vasorum?

Often young dogs
May be asymptomatic
Chronic, unresponsive coughing
Dyspnoea, haemoptysis (coughing up blood/bloody mucus)
Ill thrift, exercise intolerance, CHF
SC and retinal haemorrhages
Paresis, ocular changes

119

How do you diagnose angiostrongylosis?

Thoracic radiography (mixed pulmonary infiltrates)
Eosinophilia
Raised beta-globulins
SNAP test (for antigen)
Larvae in faeces (Baermanns)

120

How do you treat angiostrongylosis?

Fenbendazole (slowly kills over 36 hours)
Milbemycin oxime (with praziquantel)
Moxidectin (with imidacloprid)
Prednisolone if severe pulmonary changes

121

How can you prevent angiostrongylus?

Moxidectin or Milbemycin every 4 weeks

122

Describe MDVD

Acquired condition (happens over time)
Small breeds; middle-aged/older dogs
Most common cardiac disease
Idiopathic
Nodular thickening -> leakage
Cardiac valve leaflets
Proteoglycan accumulation
Cavalier King Charles Spaniel

123

Give some other names for MDVD

Myxomatous degenerative valvular disease
Degenerative valvular heart disease
Mitral endocadiosis
Chronic valvular insufficiency
Suspected genetic basis
Lengthened/ruptured chordae

124

Give the macroscopical pathology of MVDV

Left atrium dilation
Left ventricle dilation
Elongation and thickening of chordae tendinae, which may rupture
Thickened leaflets
Jet lesions may be seen in atrial endocardium

125

Describe the microscopic pathology of MDVD

Accumulation of glycosaminoglycans within the valve leaflets with disrupted collagen matrix

126

What is the difference between eccentric and concentric hypertrophy?

Eccentric: walls stay at an appropriate thickness (no change in chamber volume)
Concentric: increase in wall thickness and reduced chamber volume

127

Define MDVD

Nodular thickening of the cardiac valve leaflets associated with proteoglycan accumulation.
The atrioventricular valves (especially mitral valve) are most commonly affected, with the aortic valves being affected to a lesser extent

128

Which kind of hypertrophy is seen with MDVD and why?

Eccentric: dilated left atrium and ventricle due to chronic volume overload

129

Describe the likely presentation of a dog with MDVD

Adult dogs
Small breeds
Heart murmur-may be asymptomatic
Cough
Breathing changes
Exercise intolerance
May progress to right-sided congestive heart failure

130

Why is a chronic cough often the first clinical sign of MDVD?

Marked left atrial enlargement -> compression of the caudal mainstem bronchi `

131

How does pulmonary oedema occur with MDVD?

The increased filling pressures within the left atrium lead to backpressure in the pulmonary vasculature -> increased hydrostatic pressure and pulmonary oedema

132

When doing a physical exam on a dog with MDVD, what would you hear when auscultating the lungs?

Increased respiratory sounds
Crackles
Tachypnoea/dyspnoea
(Pulmonary oedema)

133

Give some signs of right-sided congestive heart failure

Hepatojugular reflex (squeeze abdomen at liver, does jugular pop out?)
Jugular distension
Abdominal effusion
Hepatomegaly

134

Where is the point of maximal intensity of a heart murmur in a dog with MDVD?

Over left apex (mitral regurgitation)

135

What 3 arrhythmias may be seen with MDVD?

Supraventricular premature complexes
Atrial fibrillation
Ventricular premature complexes

136

On an ECG, what does a prolonged P wave represent?

Left atrial enlargement

137

On an ECG, what does a tall R wave represent?

Left ventricular enlargement

138

On an ECG, what does a prolonged QRS represent?

Conduction disturbance

139

What value should a dog's vertebral heart scale be?

>10.5

140

What might you see on a radiograph in a dog with MDVD?

Cardiomegaly (check vertebral heart scale)
Left atrial enlargement
Lung patterns
-Prominent lobar vessels -> early pulmonary congestion
-Interstitial lung pattern -> early pulmonary oedema
-Alveolar pattern -> pulmonary oedema

141

What is the best diagnostic method for confirming MDVD?

Echocardiography

142

What would you see on an echocardiography of a dog with MDVD?

Thickened atrioventricular leaflets (may see ruptured chordae tendinae)
Enlarged left atrium (LA>LV)
Dilated, rounded left ventricle
Hyperdynamic systolic function (reduced afterload, increased preload)
Mitral regurgitation
Pulmonary hypertension

143

What other pathology may dogs with CHF have?

Pre-renal azotaemia

144

What is NT-proBNP?

Marker for heart failure
Released by atrial/ventricular stretch

145

What is Troponin I?

Marker of myocardial cell damage (part of sarcomere of myocyte)

146

Give a good treatment plan for CHF

Furosemide (diuretic, essential in CHF)
Spironolactone (weak diuretic, anti-remodelling effects)
ACE-inhibitors (vasodilators, reduce afterload)
Pimobendan (positive inotrope and vasodilator, addreses pulmonary hypertension)

147

Which drugs could you give to treat a supraventricular arrhythmia associated with MDVD?

-Diltiazem (calcium channel blocker)
-Digoxin

148

What is the estimated life span of a dog once is develops CHF?

12 months

149

What is endocarditis?

Infection of one or more endocardial valves

150

Give some infectious agents that cause endocarditis

Streptococcus spp
Staphylococcus spp
E.coli
Pseudomonas
Bartonella spp etc

151

Endocarditis is more likely to occur on which valves?

Aortic or mitral

152

What would you suspect in a case of pyrexia of unknown origin and a new heart murmur?

Endocarditis

153

What conditions are required for endocarditis to occur?

Bacteraemia (eg infections, IV catheter, surgery)
Damaged endothelium (turbulence, high velocities)
Bacteria must be able to adhere and evade host defences
Hypercoagulable states

154

Describe the pathology of endocarditis

Vegetations on endocardial surface of valve leaflets (ie atrial/ventricular surfaces)
Affected valves usually deformed; can be perforated, haemorrhagic, calcified if mature
Microscopic findings:
-Platelets, WBCs, RBCs, bacteria, fibrin
-Fibrous tissue, calcification in mature lesions
Septic/sterile arterial embolisation (kidney, heart, lung, brain)

155

Describe the pathophysiology of endcarditis

Persistent/intermittent bacteraemia -> systemic inflammatory response
Thromboembolic events (septic)
-Organ infarction
-Abscess formation
-Neurological signs
-Shifting lameness
Stimulation of humoral/cellular Immune system: Immune complex, antinuclear antibodies
-Clotting abnormalities -> DIC
-Proteinuria -> glomerulonephritis
-Polyarthritis, glomerulonephritis, myocarditis
Valvular regurgitation (mitral/aortic) leading to volume overload. Also stenosis leading to pressure overload of left ventricle.
-Increased myocardial workload
-Congestive heart failure

156

How would you diagnose endocarditis?

Blood culture
-At least 3 puncture sites, 10ml per sample
-Prior to antibiosis

Echocardiography
-Presence of valvular vegetations
-Regurgitation from affected valve

ECG
-May show tachycardia or arrhythmias

157

What clinical pathology would you see with endocarditis?

Usually neutrophilia +/- left shift
Commonly thrombocytopenia -> DIC?
Abnormalities associated with thromboembolic disease

158

How could you diagnose endocarditis using modified Duke's criteria?

Must have 2 major criteria/ 5 minor/ 1 major and 3 minor criteria

159

Give the major criteria of the modified Duke's criteria, used for diagnosing endocarditis

Positive echocargiogram
New valvular insufficiency
Positive blood culture

160

Give the minor criteria of the modified Duke's criteria, used for diagnosing endocarditis

Fever
Medium/large breed
Subaortic stenosis
Thromboembolic disease
Immune-mediated disease
Positive blood culture not meeting major criteria
Bartonella serology ≥1:1024

161

How do you treat endocarditis?

Bactericidal antibiotics based on culture and sensitivity (fluoroquinalone and potentiated amoxicilin + metronidazole whilst awaiting culture)
Minimum 6 weeks
Anti-coagulation
Monitoring of acute-phase proteins

162

What is the prognosis like for endocarditis?

Guarded-poor
-Recurrence
-Complications
-Irreversible valve damage -> volume overload and congestive heart failure

163

What is the msot common primary cardiomyopathy in dogs?

Dilated cardiomyopathy

164

What is ARVC?
Which breed is more affected?

Arrhythmic right ventricular cardiomyopathy
Boxers

165

Give some primary cardiomyopathies in dogs

-Dilated cardiomyopathy
-Arrhythmic right ventricular cardiomyopathy
-Hypertrophic cardiomyopathy
-Atrial cardiomyopathy

166

Which dog breeds are more prone to hypertrophic cardiomyopathy?

Terrier breeds, pointers, golden retriever

167

Which dog breeds are more prone to atrial cardiomyopathy?

Labrador, english springer spaniel

168

How would you recognise atrial standstill on an ECG?

No p waves

169

What can cause primary myocarditis?

Viruses (eg Parvo) and autoimmune response

170

What can cause secondary myocarditis?

Inflammation, specific pathogens (eg distemper virus, Toxoplasma, Leptospira spp. and Leishmania)

171

What happens to the heart with dilated cardiomyopathy?

-Impaired systolic function (ie reduced contractility; cell death and fatty/fibrous replacement)
-Dilated cardiac chambers

172

What causes dilated cardiomyopathy?

Idiopathic

173

What kind of dogs are affected by dilated cardiomyopathy?

-Adult onset
-Medium-large breeds (eg Doberman)

174

What can happen as a result of dilated cardiomyopathy?

-CHF
-Sudden death

175

Left ventricular hypertrophy in dogs is most likely to occur secondary to which conditions?

-Aortic stenosis
-Systemic hypertension
-Infiltrative disease

176

Why may atrial cardiomyopathy ultimately result in a pacemaker?

-Atrial wall thinning -> atrial standstill

177

Give some examples of drugs which can cause secondary cardiomyopathies

-Chemotherapy drugs eg doxorubicin/epirubicin, cyclophosphamide
-Heavy metals

178

Give some infiltrative conditions that can cause secondary cardiomyopathies

-Neoplasia
-Glycogen storage diseases, amyloidosis

179

What is the most commonly recognised nutritional cardiomyopathy?
Which breeds does it affect?

-Taurine deficiency
-Cocker Spaniels, Golden Retrievers and some Newfoundlands

180

Describe the pathology of dilated cardiomyopathy

-Dilation of any of the 4 cardiac chambers
-Increased heart weight:body weight ratio
-Thin, stretched walls
-Valvular lesions: age related, due to mitral regurgitation
caused by valvular annulus stretching
-LV thickness: LV diameter is reduced

181

What histological patterns are seen with dilated cardiomyopathy?

-Attenuated wavy fibres (atrophied) (thin myocytes)
-Fibro-fatty degeneration (vacuolation, myocyte lysis)
-ie cell death and fibrous or fatty replacement

182

How does the heart maintain blood pressure with dilated cardiomyopathy?

-Activates sympathetic nervous system (tachycardia, vasoconstriction)
-RAAS (retention of Na and fluid, increased circulatory volume, vasoconstriction)
-Remodelling-myocardial eccentric hypertrophy (improved systolic function)

183

How does dilated cardiomyopathy lead to mitral regurgitation?

-Activation of sympathetic nervous system -> intracellular Ca overload, increased O2 demand -> cell death
-Remodelling of myocardial eccentric hypertrophy -> fibrosis, increased wall stress, dilation of valvular annulus -> mitral regurgitation

184

Give some similarities between mitral degenerative valve disease and dilated cardiomyopathy

-Enlarged left ventricle (+/- right)
-Enlarged left atrium
-Mitral regurgitation

185

Give some differences between mitral degenerative valve disease and dilated cardiomyopathy

MDVD:
-Lots of mitral regurgitation
-Normal systolic function (contractility)
-Left atrium bigger than left ventricle

DCM:
-Mild mitral regurgitation
-Reduced systolic function (contractility)
-Left ventricle bigger than left atrium

186

How do dilated cardiomyopathies in dalmations differ from other breeds?

-May see ventricular premature complexes on ECG
-May be associated with nutrition (low protein diet)

187

How do dilated cardiomyopathies in cocker spaniels differ from other breeds?

-May be due to taurine deficiency
-Slow progression over many years

188

How do dilated cardiomyopathies in irish wolfhounds differ from other breeds?

-Can present with lone atrial fibrillation -> progression to overt DMC?

189

How do dilated cardiomyopathies in dobermans differ from other breeds?

-Long asymptomatic preclinical phase (2-4 yrs)
-Sudden death
-Ventricular arrhythmias
-Short survival after developing CHF (2-4 months)

190

What is arrhythmogenic right ventricular cardiomyopathy?

-Loss of myocytes with fatty/fibrofatty replacement, resulting in regional or global abnormalities
-Right ventricle

191

Arrhythmogenic right ventricular cardiomyopathy is seen mostly in which dog breed?

Boxer

192

What are the 3 types of arrhythmogenic right ventricular cardiomyopathy?

-Asymptomatic- VPCs detected by Holter monitoring
-Symptomatic (syncopal)- arrhythmias, normal systolic function
-DCM + arrhythmias

193

What is the most likely cause of arrhythmogenic right ventricular cardiomyopathy?

Genetic

194

What are the clinical signs of heart disease?

-Cough
-Tachypnoea/dyspnoea
-Exercise intolerance
-Abdominal distension (ascites/hepatomegaly)
-Synope
-Collapse?
-Increased water intake?
-Heart murmur
-Sudden death?
-No signs

195

Describe the pahtology of arrhythmogenic right ventricular cardiomyopathy

-Fibrofatty tissue replacement particularly in the right ventricle, but also the LV and often the atria
-Fatty tissue or scarring may be seen grossly
-Possibly dilated heart

196

Describe a likely clinical presentation of a dog with dilated cardiomyopathy

-Large breeds, adults
-Exercise intolerance
-Most dogs are in CHF at presentation (or can be asymptomatic)

197

Describe a likely clinical presentation of a dog with mitral degenerative valve disease

-Small breeds. adults
-Loud heart murmur

198

Where would you hear mitral regurgitation when auscultating the heart?

Left apex, 5th IC space

199

What might you find on a clinical exam of a dog with dilated cardiomyopathy?

-Cardiac cachexia (muscle wasting)
-Mm: pale, sluggish CRT
-Tachypnoea, dyspnoea
-Weak femoral pulses
-Pulmonary oedema
-Jugular distension, abdominal effusion, positive hepatojugular reflex (R-CHF)
-Cough

200

How would you identify pulmonary oedema on auscultation?

-Crackles
-Increased respiratory sounds
-Tachypnoea/dyspnoea

201

What kind of murmur may you hear with dilated cardiomyopathy?

Soft systolic murmur left apex, grade 1-4

202

What kind of murmur may you hear with mitral degenerative valve disease?

Soft systolic murmur left apex, grade 2-4

203

Which diagnostic tests can you do to diagnose dilated cardiomyopathy?

-Blood pressure
-ECG
-Thoracic radiographs
-Echocardiography

204

Which common arrhythmias may be seen with mitral degenerative valve diease?

-Supraventricular premature complexes
-Atrial fibrillation
-Ventricular premature complexes

205

Which common arrhythmias may be seen with dilated cardiomyopathy?

-Atrial fibrillation
-Ventricular premature complexes
-Supraventricular premature complexes
-Ventricular tachycardia

206

What would you see on an echocardiography of a dog with dilated cardiomyopathy?

-Enlarged left atrium
-Dilated, rounded left ventricle
-LV>LA
-Thin walls?
-Reduced systolic function
-Mild mitral regurgitation
Asynchronous contraction of LV walls

207

What would you see on an echocardiography of a dog with mitral degenerative valve disease?

-Enlarged left atrium
Dilated, rounded left ventricle
-LA>LV
-Thin walls?
-Hyperdynamic systolic function
-Lots of mitral regurgitation

208

What other clinical pathology findings may be present with dilated cardiomyopathy?

-Pre-renal azotaemia (reduced CO -> reduced renal perfusion)
-Mild increases of liver enzymes due to liver congestion
-Low albumin if effusions
-Rule out hypothyroidism

209

Give some metabolic/endocrine causes of secondary cardiomyopathies

-Hypothyroidism
-Hyperthyroidism (rare, iatrogenic)
-Systemic hypertension
-Diabetes mellitus
-Acromegaly (rare in cats, even rarer in dog)

210

What is Troponin-1?

Marker for myocardial cell damage (not specific for cardiac disease)

211

What is NT-proBNP?

-Marker for heart stretch
-May help identify failure
-Helps to assess severity of disease

212

Why might you carry out Ambulatory ECG-Holter monitoring?

-Permits diagnosis of DCM in preclinical/occult phase
(ie arrhythmias without chamber dilation and/or systolic dysfunction)
-Assessment of arrhythmias
-Assessment of response to treatment

213

What are the main principles for treating dilated cardiomyopathy?

-Inotropic support (positive inotrope -> increase contractility)
-Reduce preload
-Reduce afterload
-Control arrhythmias
-Nutraceuticals

214

How can you reduce preload in a dog with dilated cardiomyopathy?

Venodilators and diurectics:
-Furosemide (essential in CHF)
-Torasemide
-Spironolactone (anti-remodelling effects)
-Thiazide (if furosemide resistance)
-Glyceryl trinitrate (percutaneous venodilator, acute pulmonary oedema)

215

How can you provide inotropic support to a dog with dilated cardiomyopathy?

-Pimobendan (positive inotrope and vasodilator)
-Dobutamine (sympathomimetic, use in emergency situations eg no response to heart failure meds)

216

How can you reduce afterload in a dog with dilated cardiomyopathy?

Vasodilators:
-ACE inhibitors eg benazepril
-Pimobendan

217

Which drugs can you give to dogs in the preclinical stage of dilated cardiomyopathy?

-Pimobendan
-ACE inhibitors (eg benazepril)
-Prolong onset of CHF

218

How can you control atrial fibrillation in dogs with dilated cardiomyopathy?

-Diltiazem
-Digoxin
-Beta blockers (don't use in heart failure!)

219

How can you control ventricular arrhythmias in dogs with dilated cardiomyopathy?

-Lidocaine (emergency tx)
-Sotalol
-Amiodarone

220

Which neutraceuticals can you use when treating dilated cardiomyopathy?

-Omega 3 Fatty acids (for cardiac cachexia, antiarrhythmic in Boxers)
-L-carnitine, taurine
-Na+ restricted diets

221

What should you measure when treating atrial fibrillation with Digoxin?

-Check K+ levels (check serum levels 5-7 days post-tx, 6-8 hours post-pill)

222

What is the general prognosis for dilated cardiomyopathy?

-Guarded to poor (6-12 months)

223

Give some primary myocardial diseases in cats

-Hypertrophic cardiomyopathy (HCM) or Hypertrophic
(obstructive) cardiomyopathy (HOCM)
-Restrictive cardiomyopathy (RCM)
-Unclassified cardiomyopathy (UCM)
-Dilated cardiomyopathy (DCM)
-Arrhythmogenic right ventricular cardiomyopathy (ARVC)

224

Give some secondary myocardial diseases in cats

-Hypertensive cardiomyopathy
-Hyperthyroid cardiomyopathy
-Cardiomyopathy associated with other systemic disease e.g. renal failure, acromegaly (normally associated with insulin resistant diabetes mellitus) etc.

225

How would you characterise feline hypertrophic cardiomyopathy?

-Marked concentric hypertrophy of left ventricle
-Diastolic dysfunction (difficulty filling the ventricles)
-Increased HR
-Increased O2 usage, possible O2 starvation of heart muscle -> cells can die off -> arrhythmias
-Can result in CHF/blood clots in heart

226

When diagnosing feline hypertrophic cardiomyopathy, which other potential causes of concentric hypertrophy must you rule out?

-Aortic stenosis
-Systemic hypertension
-Hyperthyroidism
-Chronic renal failure
-Acromegaly (+/- diabetes mellitus)

227

What are the causes of feline hypertrophic cardiomyopathy?

-Idiopathic
-Genetic in some breeds (eg persian, ragdoll)
-Maine coon and ragdoll: mutations detected in myosin binding protein C (genetic tests available)

228

How do you diagnose feline hypertrophic cardiomyopathy?

Echocardiography
-Demonstration of concentric hypertrophy (with
wall measurements ≥ 6 mm in diastole)
-Hypertrophy is usually symmetrical, but can be focal

229

What is a 'valentine heart' on a thoracic radiograph?

-Biatrial enlargement (not specific for a particular myocardial disease, but used to diagnose hypertrophic cardiomyopathy in advanced disease)

230

What is the best method for seeing whether a cat is in left-sided congestive heart failure?

Radiography to look for pulmonary oedema

231

What 3 things seen together on a thoracic radigraph indicate pulmonary oedema?

-Left atrial enlargement
-Pulmonay venous distension
-Pulmonary infiltrate

232

Describe the source of heart murmurs in hypertrophic cardiomyopathy

-Septal bulge results in left ventricular outflow tract (LVOT) obstruction
-This may also cause the anterior mitral valves leaflet to be 'sucked' into the left ventricular outflow tract = systolic anterior motion (SAM)
-This leaves the mitral valve incompetent -> mitral regurgitation

233

What is a diastolic gallop?

The detection of S3 and S4 heart sounds

234

What is S3?

-Rapid deceleration of blood in left ventricle
-Detected if the LV is stiff or has increased pressure

235

What is S4?

-Left ventricular filling, associated with atrial contraction -Detected if there is increased dependence on atrial contraction, such as slow relaxation (as in HCM)

236

What are the clinical signs of hypertrophic (obstructive) cardiomyopathy?

-May be asymptomatic, only detected due to presence of heart murmur
-L-CHF (may have acute presentation with pulmonary oedema or thromboembolism)

237

Describe feline aortic thromboembolism (FATE)

-Stasis of blood flow in the dilated left atrium may result in thrombus formation -> thrombo-embolism to the distal aorta -> ischaemic neuromyopathy (HL paralysis)

238

How do you treat hypertrophic (obstructive) cardiomyopathy?

-Diuretics (furosemide)
-Drain a pleural effusion causing dyspnoea
-ACE inhibitors (once CHF is present, none licensed but use benazepril as licensed for renal insufficiency)
-Prevent thromboembolism (eg aspririn, clopidogrel)

239

What treatment can you use in an asymptomatic cat with hypertrophic (obstructive) cardiomyopathy?

-Beta blockers (eg atenolol) reduce severity of LVOT and SAM, slow HR (and thus improve diastolic function), reduce wall stress and stimulus to further concentric hypertrophy
-Diltiazem : positive lusiotrope (improves relaxation)
-ACE inhibitors
-All 3 classes cause a decrease in wall thickness

240

When should beta blockers never be used?

In cats with uncontrolled CHF

241

What is clopidogrel?

-Anti-platelet drug
-Used to prevent thromboembolism in HCM

242

What causes dilated cardiomyopathy in cats?

-Rare
-Taurine deficiency
-Genetics- Abyssinian/Somali cats

243

How do you diagnose dilated cardiomyopathy in cats?

Echocardiography (dilated, hypokinetic left ventricle with thin walls)

244

How do you treat dilated cardiomyopathy in cats?

-Pimobendan (positive inotrope)
-Supplement taurine
-Drain any pleural effusions
-Humidified O2
-Furosemide (diuretic)
-ACE inhibitors

245

What are the 2 forms of restrictve cardiomyopathy?

-Myocardial
-Endomyocardial

246

How would you characterise restrictive cardiomyopathy?

-Enlarged left atrium (may see 'smoke')
-Normal left ventricle
-Significant diastolic dysfunction

247

How do you treat restrictive cardiomyopathy?

-Furosemide and ACE inhibitors
-Pimobendan is indicated in the presence of impaired systolic function
-Thromboembolism-prevention meds (clopidogrel?)

248

What is an unclassified cardiomyopathy?

-Features of more than one form of cardiomyopathy

249

Arrhythmogenic right ventricular cardiomyopathy (ARVC) usually affects which kinds of cats?

-Older cats >10yrs old
-Birmans

250

What happens to the heart with arrhythmogenic right ventricular cardiomyopathy (ARVC)?

-Right ventricular myocardium becomes replaced with a fibro-fatty infiltrate

251

Give some clinical signs of arrhythmogenic right ventricular cardiomyopathy (ARVC) in cats

-R-CHF
-Ventricular arrhythmias
-Conduction disturbances
-May have pleural effusions, ascites

252

How do you treat arrhythmogenic right ventricular cardiomyopathy (ARVC) in cats?

Furosemide and ACE-inhibitors

253

How would you treat dyspnoea in a cat due to pulmonary oedema?

-Do not stress!
-Sedate (methadone or buprenorphine)
-Provide humidified O2
-Give furosemide iv e.g. 1 mg/kg every 1-2 hours
-Apply nitroglycerine topically to medial pinna (venodilator, reduces pulmonary oedema)
-Furosemide and ACE inhibitors orally long-term. Pimobendan if poor systolic function.

254

Describe the layers of the pericardium

-Outer: fibrous pericardium: tough sac that continues with the adventitia of the great vessels dorsally, and with the sternopericardial ligament ventrally
-Inner: serous pericardium: contains two layers withpericardial fluid between them. A thin
layer of mesothelial cells is present in the inner aspect of the layers.
-Parietal layer: forms the inner surface of the fibrous pericardium
-Visceral layer: forms the epicardium

255

Where does the main innervation of the pericardium come from?

-Vagus nerve (X)
-Laryngeal recurrent nerve (XI)
-Sympathetic nerve fibres
-Phrenic nerves course over lateral surfaces of pericardium (pericardial pain)

256

Where does the blood supply to the pericardium come from?

-Aorta
-Internal thoracic artery
-Musculophrenic arteries

257

Which lymph nodes drain the pericardium?

Cardiac, mediastinal and pre-sternal lymph nodes

258

How much fluid does the pericardium contain?
What is its function?

-0.25ml/kg
-Acts as a lubricant

259

Give some functions of the pericardium

-Prevents over-dilation
-Protects heart from infection
-Systolic function
-Maintains the heart in a fixed position within the thorax
-Co-ordinates function between LV and RV

260

Pericardial disease in cats is usually associated with what?

Cardiomyopathy or as an incidental manifestation of systemic disease

261

How can we classify pericardial disease?

Congenital or acquired

262

What is PPDH?

Peritoneopericardial diaphragmatic hernia

263

Give some congenital causes of pericardial disease

-Peritoneopericardial diaphragmatic hernia
-Intra pericardial cyst
-Pericardial defect/absence

264

Give some acquired causes of pericardial disease

-Pericardial effusion (eg haemorrhagic, transudtae, exudate)
-Constrictive/effusive-constrictive pericarditis

265

Describe peritoneopericardial diaphragmatic hernia (PPDH)

-Defect in ventral diaphragm and pericardium -> abdominal organs within pericardial sac
-Commonly additional sternal malformations, ventral abdominal hernias and congenital heart diseases

266

Which breeds are more prone to peritoneopericardial diaphragmatic hernias?

-Weirmaraners
-Persian cats

267

Give some clinical signs of peritoneopericardial diaphragmatic hernias

-May be asymptomatic
-May have respiratory or GI signs (depending on herniated organs)
-Apex beat may be absent/ displaced, muffled heart sounds

268

How do you diagnose peritoneopericardial diaphragmatic hernias?

Radiography, echocardiography

269

How do you treat peritoneopericardial diaphragmatic hernias?

Surgery

270

What are the most common causes of pericardial effusion?

-Idiopathic
-Neoplasia

271

Which kinds of dogs are affected by pericardial effusion?

Older, large breed dogs

272

Which kinds of cats are affected by pericardial effusion?

Cats with CHF and systemic disease (eg FIP)

273

Give some other, less common causes of pericardial effusion

Lymphoma, rhabdomyosarcoma, bacterial pericarditis (after dog bite, trauma), coccidiomycosis, aspergillus, coagulation disorder, uraemia

274

How could you treat an idiopathic pericardial effusion?

Pericardiectomy if it recurs for 3rd time (also allows for pericardial biopsy and exploratory thoracotomy)

275

Which neoplasia types can cause neopalstic pericardial effusion?

-Haemangiosarcoma
-Chemodectoma/aortic body tumour (heart base tumour)
-Mesothelioma
-Others eg lymphoma

276

Which dog breeds are more prone to haemangiosarcomas causing neoplastic pericardial effusion?

-GSD
-Golden Retriever
-Setters

277

Describe a haemangiosarcoma causing neoplastic pericardial effusion

-Right atrium/right auricular appendage
-Commonly spleen +/- liver also affected
-Quick recurrence of effusion after pericariocentesis
-Grave prognosis (MST=6 months)

278

How can you treat a haemangiosarcoma causing neoplastic pericardial effusion?

-Palliative: pericardiocentesis, pericardiectomy, balloon pericardiotomy
-Chemotherapy +/- surgery

279

Which dog breeds are more prone to chemodectomas causing neoplastic pericardial effusion?

-Brachycephalics (older dogs)

280

Describe a chemodectoma

-Benign, slow-growing tumour at the heart base
-Locally invasive but low metastatic rate

281

How do you treat a chemodectoma?

-Palliative pericardiectomy
(Can't surgically remove)

282

How do you treat a mesothelioma of the pericardium?

-Difficult to treat
-Intracavitary cisplatin, IV doxorubicin

283

Describe the pathophysiology of pericardial effusion

Accumulation of fluid within the pericardial sac impedes ventricular filling of the heart during diastole

284

Describe the pathophysiology of chronic pericardial effusion

-Decreases stroke volume -> activates RAAS and sympathetic system -> peripheral vasoconstriction, increased heart rate and fluid retention
-Cardiac tamponade: collapse of RA (sometimes RV) during diastole (due to elevated intrapericardial pressures)
-Venous return to the heart is compromised -> R-CHF
-Pulsus paradoxus (no/reduced pulse during inspiration)

285

Give the clinical signs of pericardial disease

Non-specific:
-Lethargy
-Decreased appetite
-Vomiting
-Diarrhoea
-Increased panting
-Increased thirst

Specific signs:
-Abdominal enlargement
-Decreased exercise tolerance
-Syncope/collapse
-Respiratory distress

286

How would you identify pericardial disease on a clinical exam?

Usually presents as R-CHF with muffled heart sounds and weak femoral pulses so may see:
-Ascites (abdominal fluid wave)- ballotment
-Jugular distension
-Positive hepatojugular reflux
-Hepatomegaly/splenomegaly
-Muffled heart sounds ie apex beat
-Weak femoral pulses- pulsus paradoxus (not always present)
-Tachycardia

287

How do you diagnose pericardial disease?

-PCV
-Haem, biochem (commonly find pre-renal azotaemia, increased liver enzymes, anaemia)
-Blood pressure (can be hypotensive due to severe forward failure, haemorrhagic shock)
-ECG
-Radiography
-Echocardiography
-Abdominal US (to look for neoplasia/concurrent disease)

288

What would you see on a radiograph of an animal with pericardial effusion?

-Globoid enlarged cardiac silhouette
-Dorsal deviation of trachea
-Dilated caudal vena cava
-Small pulmonary vessels
-Abdominal effusion
-Pericardial fluid analysis

289

What would you see on an ECG of an animal with pericardial effusion?

-Small complexes
-Sinus tachycardia
-Differences in height of QRS complexes due to movement of heart swinging in the fluid

290

What would you see on an echocardiography of an animal with pericardial effusion?

-Presence of hypoechoic (black) fluid around the heart
-Hyperechoic (white) pericardial line surrounding the fluid
-Collapse of the right atrium (tamponade)
-Swinging of the heart within the fluid
-Pleural effusion might also be present

291

What should you do with pericardial fluid when investigating a pericardial effusion?

Send for cytology +/- culture

292

What does pericardial fluid look like?

-Sanguineous/serosangineous
-Dark red color

293

What is cardiac tamponade?

Collapse of RA (sometimes RV) during diastole (due to elevated intrapericardial pressures)

294

How do you treat a pericardial effusion?

-NOT DIURETICS!
-If tamponade is present, prompt pericardiocentesis is the only tx option
-High-rate fluids can be given IV to increase cardiac pre-load

295

What should you check before doing a pericardiocentesis?

PCV

296

Why should you not use diuretics when treating pericardial effusion?

-Will further reduce the cardiac pre-load and worsen cardiac tamponade

297

What hapens on an ECG following pericardiocentesis?

-QRS complexes usually become bigger and heart rate decreases after drainage, occasional VPCs towards the end of procedure

298

Why should you check PCV of pericardial fluid when doing pericardiocentesis?

If PCV is same as patients own blood-STOP! Probably haemorrhagic effusion

299

Where should you perform pericardiocentesis?

5th - 6th intercostal space

300

Give some complications of performing pericardiocentesis

-Pneumothorax (due to rapid increase in left heart filling)
-Arrhythmias (usually self-limiting): atrial fibrillation (due to sudden expansion of atrias), ventricular arrhythmias
-Coronary lacerations, intracardiac puncture, pneumothorax (rare)

301

Describe the pericardium with costrictive/effusive-constrictive pericarditis

Thickened, fibrotic, non-distensible

302

What may cause constrictive/effusive-constrictive pericarditis?

Idiopathic or secondary to:
-Recurrent pericardial effusion
-Neoplasia
-Foreign body
-Infectious pericarditis

303

Give some clinical signs of constrictive/effusive-constrictive pericarditis

R-CHF and cardiac tamponade

304

How do you treat constrictive/effusive-constrictive pericarditis?

Pericardectomy and surgical stripping of the fibrotic pericardium

305

What is the prognosis for surgical stripping of the fibrotic pericardium?

Guarded-grave

306

Which kinds of dogs can suffer from left atrial rupture/tears?

Small breeds with advanced mitral valve disease and severe LA enlargement (uncommon)

307

How can you treat left atrial rupture/tears?

-Pericardiocentesis, blood transfusion, thoracotomy to remove clots and repair atrium
-Guarded-grave prognosis

308

Give some causes of infectious/inflammatory pericarditis

-Foreign body, penetrating wound (dog bite, trauma), infectious agent
-FIP in cats

309

How do you treat infectious/inflammatory pericarditis?

Aggressive antibiosis

310

Innocent puppy heart murmurs should be gone by which age?

6 months

311

Which side of the heart is affected by patent ductus arteriosus?

Left

312

Describe patent ductus arteriosus

-Shunt from descending aorta to pulmonary artery (left to right shunt)
-Continuous murmur
-Continuous run-off of blood into pulmonary circulation
-Pulmonary over-circulation (increased pulmonary vessel size on radiographs)
-Volume overload of left atrium and ventricle
-Dilation of mitral valve annulus -> mitral regurgitation
-L-CHF by 7rs old if untreated

313

Which breeds and sex of dogs are more afected by patent ductus arteriosus?

-Collies, Bichon Frise, CKCS, GSD
-Female

314

How does the femoral pulse sound with patent ductus arteriosus?

-Bounding, 'water hammer'

315

Describe Eisenmenger’s physiology

-In some cases of PDA, if pulmonary arterial pressures are sufficiently increased, the shunt may then reverse, from the pulmonary artery to the descending aorta (reverse PDA)
-The murmur may disappear (equalisation of pressures between aorta and pulmonary artery)
-Animal may show caudal cynosis, and will present with HL weakness or collapse
-Rare in dogs, more common in cats with PDA

316

Give the clinical signs of patent ductus arteriosus

-Initially may be asymptomatic
-Continuous murmur, left axilla, may radiate
-Secondary murmur (systolic, mitral regurgitation)
-Rapidly collapsing femoral pulse ('water hammer')

317

How do you diagnose patent ductus arteriosus?

-Radiography
-ECG
-Doppler echocardiography

318

What would you see on a radiograph of patent ductus arteriosus?

-Left atrial and left ventricular enlargement
-Increased size of pulmonary vessels (over-circulation)
-'Triple knuckle effect': enlargement of pulmonary artery, aorta and left auricular appendage

319

What would you see on an ECG of patent ductus arteriosus?

-Evidence of LA and LV enlargement
-P mitrale (wide p wave -> left atrial enlargement)
-Tall r waves -> left ventricular hypertrophy

320

What would you see on an echocardiography of patent ductus arteriosus?

-Diastolic turbulence in the pulmonary artery
-Enlarged left atrium and ventricle, dilated pulomary trunk
-Ductus entering pulmonary artery

321

How do you treat patent ductus arteriosus?

Surgery:
-Ligation of ductus
-Device-based occlusion of the ductus by cardiac catheterization (devices encourage clot formation which occludes flow)

322

What is the most common congenital heart defect in dogs?

Aortic stenosis

323

Give some dog breeds that are predisposed to aortic stenosis

GSD, Boxer, Newfoundland, Rottweiler

324

How can the left ventricle be affected by aortic stenosis?

Pressure overload on left ventricle -> concentric hypertrophy (smaller lumen size)

325

Give some clinical signs of aortic stenosis

-Exercise intolerance
-Syncope
-Ventricular arrhythmias if coronary perfusion is compromised
-L-HF (rare)

326

Where is the point of maximal intensity of an aortic stenosis murmur?

Left base (radiates to right heart base and thoracic inlet)

327

What would you see on a radiograph of aortic stenosis?

May see aortic arch bulge

328

Describe the heart murmur heard with aortic stenosis

Harsh, ejection-type, heard between 1st and 2nd heart sounds

329

What may you see on an ECG of aortic stenosis?

-Tall r waves, prolonged QRS (left ventricular enlargement and hypertrophy)
-Ventricular premature complexes (QRS without a p)

330

What may you see on a doppler echocardiography of aortic stenosis?

-Valvular/subvalvular lesions
-Post-stenotic dilation of aorta
- Turbulence in the LV outflow tract and aorta (velocities >2.0 m/s)

331

How do you convert Doppler velocity into pressure gradient?

-Modified Bernouilli equation
P=4v2 (squared)

332

Which value represents normal aortic velocity?

<1.7m/s

333

Give the pressure gradient values of mild, moderate and severe aortic stenosis

0-40mmHg= mild
40-80mmHg= moderate
>80mmHg= severe

334

Breed schemes for aortic stenosis exist for which dog breeds?

Boxer and Newfoundland

335

How do you treat aortic stenosis?

-No real treatment
-Beta blockers may reudce risk of sudden death in dogs with syncope
-If in CHF, give diuretics
-Avoid positive inotropes (eg pimobendan)

336

Give some dog breeds which are predisposed to pulmonic stenosis

-Boxer
-Bulldogs
-Bull mastiffs
-Cocker spaniels
-WHWT

337

How does pulmonic stenosis usually occur?

Valves are fused together or have dysplastic valve leaflets (RHS)

338

Where do coronary arteries arise from?

Aorta

339

What are the clinical signs of pulmonic stenosis?

-Mid to holo-systolic heart murmur, left heart base, radiating dorsally
-Syncope
-Exercise intolerance
-May be asymptomatic

340

How does pulmonic stenosis affect the right ventricle?

-Increased pressure load on right ventricle -> concentric right ventricular hypertrophy and marked increases in right ventricular pressure
-RV hypertrophy may lead to myocardial ischaemia ->ventricuar arrhythmias

341

How do you diagnose pulmonic stenosis?

-Radiography
-ECG
-Doppler echocardiography

342

What would you see on a radiograph of pulmonic stenosis?

-Right sided enlargement (increased sternal contact) (reverse D shape on DV view)
-Dilation of pulmonary artery (bulge at 1 or 2 o'clock on DV radiograph)

343

What would you see on an ECG of pulmonic stenosis?

-Right ventricular enlargement and hypertrophy
-Deep s waves in leads I, II and aVF

344

What would you see on a doppler echocardiography of pulmonic stenosis?

-Interventricular septum may be flattened and pushed into the LV
-Dysplastic pulmonic valves
-Post-stenotic dilation of pulmonary valves
(Pressure overload of right ventricle)

345

How do you treat pulmonic stenosis?

-Balloon vulvoplasty of pulmonic valve (cardiac catheterisation) (aim is to reduce pressure gradient by 50%)

346

How is murmur grade related to severity of disease with ventricular septal defects?

-Inversely proportionate
-Small defects= large murmurs
-Large defects= quiet murmurs

347

Where are vetricular septal defects located in small animals?

-In the peri-membraneous septum, “between” the aortic and tricuspid valve leaflets

348

What kind of shunt is most commonly seen in ventricular septal defects? Why?

-Left to right shunt
-Most defects are small and restrictive -> pressure gradient is maintained between LV and RV

349

How does a ventricular septal defect affect the ventricles?

-Left to right shunt -> volume overload in right ventricle -> pulmonary over-circulation -> LA and LV volume overload

350

How do you diagnose ventricular septal defects?

-Radiography
-ECG
-Echocardiography

351

What would you see on a radiograph of a ventricular septal defect?

-Left sided and right ventricular enlargement
-Pulmonary over-circulation (increased size of lobar vessels)

352

What would you see on an ECG of a ventricular septal defect?

-May be normal or show changes consistent with biventricular enlargement (deep Q waves, tall R waves) or left atrial enlargement (p mitrale)

353

What would you see on a doppler cardiography of a ventricular septal defect?

-Facilitates detection of the shunt

354

Give some possible sequelae to ventricular septal defects

-Small restrictive VSDs remain asymptomatic
-Large defects: L-HF
-Occasionally, the aortic valve leaflet may “prolapse” into the defect -> aortic incompetence (regurgitation) and possibly an audible diastolic murmur
-If pulmonary hypertension is present, high RV pressures may result in shunt reveral (Eisenmenger's syndrome)

355

What is Eisenmenger's sydrome?

-Rare consequnece of a ventricular septal defect
-If pulmonary hypertension is present, high RV pressures may result in shunt reveral (as RV pressure is greater than LV pressure)
-Cyanosis of mm
-Occurs before 6 months old
-May develop polycthaemia (due to renal hypoxia)

356

Which dog breeds are predisposed to mitral valve dysplasia?

Bull terriers, golden retrievers, great danes, GSD

357

Whcich dog breed is predisposed to tricuspid dysplasia?

Labradors (canine chromosone 9)

358

Describe the pathophysiology of mitral/tricuspid valve dysplasia

-Incompetece of valve with regurgitation
-Volume overload of atrium or ventricle
-Heart failure
-Possibly arrhythmias
-Occasionally get stenosis of valve -> gross atrial enlargement

359

How may the valve be different from normal in mitral/tricuspid valve dysplasia?

-May be thickened
-May have abnormal papillary muscles or chordae tendinae

360

How might the mitral valve appear on doppler cardiography with mitral valve dysplasia?

'Hockystick' appearance

361

What might you see on a doppler cardiography of tricuspid valve dysplasia?

Right atrium bigger than left atrium

362

Which direction ins shunting with atrial defects?

Usually left to right, except in conditions with raised right atrial pressure (eg concurrent pulmonic stenosis)

363

How do you diagnose atrial septal defects?

Doppler echocardiography

364

Give the components of Tetralogy of Fallot

-Pulmonic stenosis -> high RV pressure
-Right ventricular hypertrophy
-Ventricular septal defect (right to left shunt)
-Dextrapposed aorta (aorta positioned more to the right than normal -> compresses pulmonary artery)

365

How may an animal present if it has Tetralogy of Fallot?

-Cyanotic (and fails to respond to O2 supplementation)
-May become polycythaemic -> increased blood viscosity -> increased work load on heart

366

Give some other congenital heart conditions that are not associated with a heart murmur

-Vascular ring anomalies
-Pericardio-peritoneal diaphragmatic hernia

367

Describe vascular ring anomalies

-Usually a persistent right fourth aortic arch
-Results in a vascular ring surrounding the oesophagus
-Mega-oesophagus rostral to the ring can occur

368

Give a clinical sign of vascular ring anomalies

Regurgitation at the onset of weaning/intake of solid foods

369

Give some examples of bronchodilators

Terbutaline
Theophylline
Etamiphylline camsilate
(B2 agonists)

370

Give an example of a mucolytic

Bromhexamine

371

What is 'feline asthma'?

Eosinophilic bronchopneumopathy (EBP)

372

What are the clinical signs of feline asthma?

Cough
Can have severe dyspnoea (expiratory)
May hear expiratory wheezes on auscultation

373

What might you hear on cardiac auscultation of a dog with a pulmonary thromboembolism?

Loud S2 (due to pulmonary hypertension and delayed closure of pulmonic valve)

374

Give some causes of pleural effusion

Increased hydrostatic pressure
Decreased plasma oncotic pressure
Increased vascular or pleural permeability (eg inflammation)
Increased fluid production (eg infection)

375

Why may a blood clot form? (3)

Circulatory stasis
Endothelial injury
Hypercoagulable state
(Virchow's triad)

376

What is the difference between eccentric and concentric ventricular hypertrophy?

Eccentric: volume overload. Wall thickness increases in proportion to the increase in chamber radius
Concentric: chronic pressure overload. Wall thickness increases but chamber radius does not change -> stiff ventricle

377

What is S1?

Sound of AV valves snapping shut

378

What is S2?

Ventricles relax and semi-lunar valves snap shut

379

What is S3?

'Gallop'
End of early diastolic filling -> vibration in ventricle

380

What is S4?

During late diastolic filling, the atria contract, squeezing more blood into an already-full ventricle

381

How do you calculate cardiac output?

HR x SV

382

Define stroke volume
How do you calculate it?

Volume of blood pumped from left ventricle per beat
End diastolic volume-end systolic volume

383

Where does the myocardium obtain most of its blood supply?

Coronary circulation

384

Where are the heart valves located?

Tricuspid: rib space 5, right axilla

Pulmonary: rib space 3
Aortic: rib space 4
Mitral: rib space 5
(all left axilla)

385

On an ecg, what does a tall p wave mean?

P pulmonale (R atrial enlargement)

386

On an ecg, what does a wide p wave mean?

P mitrale (L atrial enlargement)

387

On an ecg, what does a tall r wave mean?

Ventricular enlargement

388

On an ecg, what does a wide r wave mean?

Left ventricular enlargement and hypertrophy

389

On an ecg, what does it mean if you have no p waves?

Atrial fibrillation
Irregularly irregular ventricular rhythm
Normal narrow QRS complexes

390

Give some diseases associated with secondary systemic hypertension?

Chronic renal disease
Hyperthyroidism (cats)
Hyperadrenocorticism
Diabetes mellitus

391

Give some consequences of systemic hypertension

Ocular (retinal detachment, hyphaema, retinal haemorrhage, blindness)
CNS (seizures, depression)
Renal (failure, proteinuria)

392

How do you treat systemic hypertension?

Amlodipine (calcium channel antagonist)
Can use ACE inhibitors to protect the kidneys (reduce glomerular capillary pressure)

393

How do you measure vertebral heart score?
What are the normal values in dogs and cats?

Measure long axis and short axis of heart on a radiograph. Transpose each onto vertebral column (from T4) and add the number of vertebrae.
Dog: >10.5
Cat: 8

394

Which receptors do beta blockers act on?

Beta adrenergic receptors (epinephrine/norepinephrine)

395

What effects do beta blockers have?

Reduce HR
Prolong diastole
Decrease CO
Decrease BP

396

On an echocardiogram, what should the ratio in size of the left atrium to aorta be?

1.5:1

397

How will the left ventricle act on an echocardiogram in a dog with mitral valve disease?

Will be hyperkinetic to compensate for the mitral valve regurgitation

398

How do you diagnose a sinus arrhythmia?

ECG (regularly irregular)

399

What effect does Pimobendan have on heart size?

Decreases it

400

Where does the left atrium sit in the chest?

Between the caudal lobar bronchi

401

Where should the trachea lie on a radiograph?

Parallel to the sternum

402

In which breed can we allow for a bigger vertebral heart score than normal?

CKCS

403

Is CHF always primary or secondary?

Secondary

404

How do you treat feline hypertrophic cardiomyopathy?

Beta blockers (eg atenolol) to reduce HR and enhance filling and relaxation of ventricles
Calcium channel blockers (eg Diltiazem)
Diuretics if in CHF (furosemide, spironolactone)
Anticoagulants (eg aspiring, clopidogrel)

405

How do ACE-inhibitors work?

Cause vasodilation by inhibiting RAAS
-> reduces preload and afterload

406

On an US, what are 'wet lungs'?
What do they indicate?

Bright white lines arising from the pleura and radiating away from the probe
Indicates conditions such as pulmonary oedema, pneumonia, contusions

407

How does Pimobendan work?

Positive inotrope
PD-3 inhibitor
Causes vasodilation
Premature use can cause left ventricular hypertrophy

408

Which lung lobe sites over the heart in a left lateral radiograph?

Right middle

409

What is the only way to diagnose arrhythmias?

ECG

410

How do you estimate mean electrical axis on an ECG?

Look for the lead with the largest QRS complex, or the isoelectric lead (
r wave =s wave) and pick the lead perpendicular to it

411

What would we expect a normal MEA value to be?

+40 to + 100
(as this is roughly where Lead II is)

412

When might you see a bifid p wave on an ECG?

Large breed dogs

413

What would you suspect if the height of the r wave changes throughout the ECG?

Heart is swinging in chest due to pericardial effusion ('electrical alternans')

414

What is a consolidated lung?

Filled with fluid eg blood, pus, oedema

415

The Dirofilaria antigen test only detects what?

Mature females

416

What can you do if you suspect pleural effusion in a severely dyspnoeic animal?

Radiographs may cause stress so do a standing US to look for fluid
With animal in sternal recumbency and giving oxygen, do 'blind' or US-guided thoracocentesus
Use 21G 1" needle, at 7-8th intercostal space. If +ve tap, continue to drain and submit samples for analysis

417

What is the difference between a transudate and modified transudate, appearance-wise?

Transudate: clear, watery
Modified transudate: straw-coloured, serosanguinous, slightly viscous

418

What is the difference between a transudate, modified transudate and exudate in terms of cytology and analysis?

Exudates have higher protein levels and are more cellular, followed by modified transudates, then transudates

419

Give some possible causes of transudates and modified transudates in a pleural effusion

Transudate: hypoalbuminaemia
Modified transudate: right-sided or biventricular CHF, diaphragmatic rupture, neoplasia

420

How do you treat pleural effusion after thoracocentesis?

If due to pericardial effusion, rapidly carry out pericardiocentesis
If due to CHF, treat as CHF
If due to hypoproteinaemia, investigate and treat underlying cause

421

Give some examples of appearance of an exudative pleural effusion

Bloody
Non-septic inflammation: viscous, straw-coloured
Septic inflammation: viscous, turbid, purulent
Chylous (milky)

422

Give some possible causes of an exudative pleural effusion

Bloody: trauma, neoplasia, coagulopathy
Non-septic inflammation: lobe torsion, neoplasia, chronic chylothorax
Septic inflammation: ruptured oesophagus, FB, pylothorax, fungal infection
Chylous: idiopathic, CHF, trauma, lobe torsion, cranial vena cava obstruction

423

How do you treat pyothorax?

Do C&S on thoracocentesis and base ABs off the results.
Initially, start combination of ABs for broad-spectrum coverage (eg metronidazole, potentiated amoxycillin, fluoroquinalone)
When stable, insert chest drain under GA
Daily thoracic lavage (up to 20ml/kg warm saline)
Once lavage is clear, can pull drains
Continue ABs for 2-3 months

424

How do you treat chylothorax following thoracocentesis?

Treat underlying cause (eg CHF)
Feed low fat diet (high CHO) (reduces chyle production)
Add medium-chain triglycerides to diet?
Rutin may reduce chyle formation (20-50mg/kg q8hrs)
Consider surgery

425

Give some causes of ventricular ectopics

Underlying cardiac disease
Catecholamines (eg stress, pain)
Acidosis
Hypokalaemia
Abdominal disease
Thoracic trauma

426

Give some underlying causes of brady-arrhythmias

High vagal tone
Hyperkalaemia
Hypothyroidism
Drug side-effects

427

How would you recognise atrial standstill on an ecg?

No p waves
Normal QRS complexes
T waves are spiky and symmetrical

428

What causes atrial standstill?

Hyperkalaemia

429

What would you see on an ecg of sinus arrest?

Period of no heartbeat followed by a junctional escape complex

430

What can cause pulse deficits?

Atrial fibrillation

431

Which sedatives should you avoid when sedating a dog with MDVD?

Alpha 2's

432

How are veins positioned on a radiograph?

Ventral and central (always travel with an artery and an airway; artery, airway, vein)

433

What could you give to treat preclinical MDVD?

Pimobendan
Can halt progression of MDVD to CHF

434

Which drugs could you give to treat a ventricular arrhythmia associated with MDVD?

Sotalol
Mexillitine? (sodium channel blocker)
Amiodarone

435

Which drugs could you give to treat pulmonary hypertension associated with MDVD?

Sildenafil (vasodilator)
Pimobendan (vasodilator)

436

What is the normal urine protein:creatinine ratio?

<0.2

437

What would you see on an ECG of supraventricular premature complexes and why?

Premature p waves (premature activation of atria from a site other than sinus node)

438

What is the normal number of VPCs you would tolerate in an ambulatory ecg of a normal dog?

<4/24 hours

439

What does the sternal lymph node drain?

Cranial abdomen and thoracic wall

440

Why may a heart have increased sternal contact on a radiograph?

RV enlargement

441

How would you diagnose right arrhythmogenic ventricular cardiomyopathy on a halter ECG?

>1000 ventricular premature complexes over 24 hours

442

Where do nasopharyngeal polyps arise from in cats?

Auditory (Eustachian) tube or tympanic bulla
Extend into pharynx or along external ear canal