SA Respiratory and CV Flashcards
(442 cards)
1
Q
What is the function of a cough?
A
Removes material from airways:
Assists mucociliary clearance
Expels inhaled material
Protects against inhaling particles/inhalants
2
Q
Where are mechanoreceptors located?
What about chemoreceptors?
A
Mechanoreceptors: larger airways
Chemoreceptors: medium airways
3
Q
Where are cough receptors most numerous?
A
Larynx > trachea > bifurcation > bronchi
4
Q
Give some common differential diagnoses of coughing
A
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
Q
Chronic bronchitis is mainly seen in which kinds of dogs?
A
Small breed dogs
6
Q
How should a cat’s thorax feel when compressed?
A
Springy
7
Q
What might you see on a radiograph of a dog with chronic bronchitis?
A
‘Tram lines’
Rings- thickened bronchial walls
8
Q
Give some characteristic changes to the bronchi caused by chronic bronchitis
A
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
Q
How does a dog with chronic bronchitis present?
A
Chronic cough with attempts at production
Worse on excitement
10
Q
Can you cure chronic bronchitis?
A
No, therapeutic goal is to manage it with bronchodilators and steroids (anti-inflammatory glucocorticoids). Avoid systemic steroids to prevent weight gain
11
Q
How can you investigate a suspected chronic bronchitis case?
A
Thoracic radiographs
Haematology
Bronchoscopy
Bronchoalveolar lavage to obtain samples for cytology/bacteriology/parasitology
12
Q
When doing a bronchoalveolar lavage in a dog, how much saline should you use?
A
1/2ml per kg bodyweight
13
Q
If you see worms on a tracheobronchoscopy what are they likely to be?
A
Crenosoma vulpis (fox lungworm)
14
Q
When you do a bronchoalveolar lavage, how much fluid should you expect to aspirate back?
A
50%
15
Q
What cells are normal to see on a BAL fluid analysis?
A
Goblet cells
Ciliated columnar epithelial cells (CCECs)
16
Q
If you see macrophages containing bacteria on a BAL fluid analysis, what does this tell you?
A
There is an active infection
17
Q
What are the normal values in BAL fluid analysis for: WBC Macrophages Neutrophils Lymphocytes Eosinophils
A
WBC: <5x10^9/l Macrophages: 70% Neutrophils: 20% Lymphocytes: 10% Eosinophils: <20-25%
18
Q
What would you see on a cytology of BAL fluid in chronic bronchitis?
A
Increased mucous, neutrophils, macrophages
Possibly squamous metaplasia of normal ciliated columnar epithelial cells
Presence of bacteria/particulate matter
19
Q
If you do a BAL in a dog with chronic bronchitis and you see Simonsiella, what does this mean?
A
Oral contamination
20
Q
How can you manage chronic bronchitis (non-medically)?
A
Weight control
Harness rather than collar
Avoid irritants/smoking environment
Mucous is easier to shift if hydrated-avoid dry environments
21
Q
Give the functions of bronchodilators
A
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
Q
Give some functions of glucocorticoids
A
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
Q
Would you give antibiotics when treating chronic bronchitis?
A
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
Q
If you decide to use antibiotics when treating respiratory tract infections, what criteria should it fit?
A
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
