Cardiology Flashcards
What are the 7 causes of a large abdomen?
Fat
Fluid
Foetus
Flatulence
Faeces
Tumour
Organomegaly
What can cause low protein transudate in the abdomen?
Portal hypertension (chronic liver disease)
Severe hypoalbuminemia
Non-exfoliating neoplasia
What can cause high protein (modified) transudate?
Right sided heart failure
Liver disease
Non-exfoliating neoplasia
Sinusoidal hypertension
What fluid is rare to find in the abdomen?
Chylous
What can cause the presence of exudate in the abdomen?
Infection
Ruptured/leaking viscus
Underlying cancer
Pancreatitis etc.
What types of fluid can be find in the abdomen?
Low protein transudate
High protein (modified) transudate
Chylous (rare)
Exudate
Bile/urine
FIP
Blood
What can cause blood in the abdomen?
Trauma
Ruptured tumour (e.g hemangiosarcoma)
Bleeding disorder
What is considered an innocent murmur in the young dog?
Low grade with the point of maximum intensity over the left heart base. Intensity can vary with heart rate. They have usually resolved by 6 months of age.
What types of heart murmur are there?
Pathological, physiological or innocent.
What does PMI stand for?
Point of maximum intensity
Name the 4 common congenital heart defects
Aortic stenosis (AS)
Patent ductus arteriosus (PDA)
Pulmonary stenosis (PS)
Ventricular septal defect (VSD)
What is an aortic stenosis?
Narrowing of the aorta
What is the most common type of aortic stenosis?
Sub-aortic stenosis
What breeds are pre-disposed to sub-aortic stenosis?
Boxers, Newfoundland and Golden retrievers.
What are common findings of aortic stenosis?
Lethargy
Exertional weakness
Syncope
Sudden death occurs in approximately 1/3 dogs with SAS.
What would you hear on auscultation of sub-aortic stenosis?
Harsh systolic ejection murmur, PMI over aortic valve.
Precordial thrill at the left heart base
Radiates to right heart base
What are the 5 types of pulmonic stenosis?
Infundibular
Sub-valvular pulmonic stenosis (uncommon)
Valvular pulmonic stenosis (common)
Supra-valvular (rare)
Anomalous coronary artert
What breeds are pre-disposed to pulmonic stenosis?
Small breeds like terriers and bulldogs
What are clinical signs of pulmonic stenosis?
Right sided heart failure
Syncope
Exercise intolerance
Sudden death if severe
Asymptomatic
What will you hear on auscultation with pulmonic stenosis?
PMI murmur left heart base with radiation cranially and ventrally
Prominent jugular pulses.
What is a patent ductus arteriosus (PDA)?
Blood shunting from aorta into pulmonary artery and continuous murmur.
Can patent ductus arteriosus (PDA) be inherited?
Yes
What does auscultation detect with a PDA?
Continuous machinery murmur with PMI left heart base. Hyperkinetic pulses.
Where are ventricular septal defects (VSD) typically found in the dog?
High in the membranous parts of the septum just below the aortic valve and under the tricuspid leaflet.
What can a moderate/large VSD cause?
Volume overload of the pulmonary trunk, circulation, LV and RV.
Can result in left sided CHF.
Clinical signs of ventricular septal defects (VSD)
Asymptomatic
Exercise intolerance
LCHF
What can be heard on auscultation of a dog with a ventricular septal defect?
Systolic murmur. PMI cranial right sternal border.
+/- murmur of functional pulmonic stenosis.
What is the most common form of acquired valvular disease?
Chronic degenerative valvular disease (CDVD)
What are the other names for chronic degenerative valvular disease (CDVD)?
Chronic (mitral) valve disease (CVD)
Endocarditis
Myxomatous mitral valve disease
What pathology is seen with endocarditis?
Thickening and redundancy of the heart valve leaflets. Most pronounced at the free margins of the valves.
Can result in MV prolapse.
What are the 4 classes of valvular disease?
1 - Small, discrete nodules along the valve edge
2 - Thickened free edges and irregular
3 - Valve edges grossly thickened and nodular with extension of lesions
4 - Further severity
What dogs are pre-disposed to valvular disease?
Middle to older small breeds (CKCS, poodles, Maltese)
What can be heard on auscultation of valvular disease?
PMI on left apex radiating dorsally and to right thorax. Murmur grade is approximate to severity.
If stable, what diagnostics should be done for valvular disease?
Thoracic radiographs
Echocardiology
Electrocardiogram
Biochemistry
Blood pressire
What abnormalities can be detected on a thoracic radiograph with mitral valve disease/ left sided cardiomegaly?
Straightening of the distal tracheal
Increased cardiac silhouette height
Straightening of caudal border of the heart
Loss of cardiac waist
Tenting of the LA
Splitting of mainstream bronchi
Bulge on cardiac silhouette at 2/3 o clock
What are the normal approximate measurements of the heart on radiography?
Height should not exceed 2/3rds the depth of the thorax
Normal vessels don’t exceed 3/4 of proximal 1/3 4th rib.
Clinical signs of ruptured chordae tendonae
Acute emergency
Severe dyspnoea
Stressed/panicking
Cyanotic
Severe LCHF
What is the definition of systemic hypertension?
Persistently elevated systemic blood pressure
What approximate blood pressure values may indicate systemic hypertension?
Systolic >160 mmHg
Diastolic >100 mmHg
What are 3 initiating causes systemic hypertension?
Chronic fluid accumulation
Persistently increases heart rate
Chronic vasoconstriction
What can hypertensive retinopathy cause?
Acute blindness
Retinal detachment
Intraocular haemorrhage
What can hypertensive encephalopathy cause?
Disorientation, ataxia, stupor, seizures, strokes
What are the two non-invasive ways to measure blood pressure?
Doppler
Oscillometer
How to take a blood pressure reading?
Quiet and comfortable area (preferably without owner)
Allow patient to acclimatise for 5 to 10 minutes.
Sedation should be avoided. Use gentle restraint in a comfortable position.
When should systemic hypertension be treated?
Risk of end organ damage
Underlying disease identified
Clinical signs
What is the action of beta blockers?
Reduce heart rate and contractility
Drugs: Atenolol, propranolol
What is the action of ACE inhibitors?
Block the RAAS pathway
Drugs: Benazepril, Enalapril, Imidapril
What is the action of Ca channel blockers?
Inhibit calcium influx to the cell
Drugs: Amlodipine
What are the 5 causes of pulmonary hypertension?
- Alveolar hypoxia with pulmonary vasoconstriction/remodelling
- Pulmonary vascular obstructive disease
- Pulmonary overcirculation
- High pulmonary venous pressure
- Idiopathic
What are the risks of chronic pulmonary venous hypertension?
Structural changes to pulmonary capillaries
Increase the muscularity of resistance arterioles
Pulmonary oedema
Hypoxia
RV hypertrophy and dilation
RCHF
When should pulmonary hypertension be suspected?
Persistent respiratory difficulty
Fatigue
Exercise intolerance
What does fluid accumulation cause with left sided chronic heart failure?
Pulmonary oedema as the back log is to the lungs through the pulmonary veins.
What does fluid accumulation cause with right sided chronic heart failure?
Ascites and pleural effusion as the back log is to the body via the cranial and caudal vena cava.
What drugs can improve heart contractibility?
Digoxin
Pimobendane
Dobutamine
What are the goals of heart failure treatment?
Control salt and water retention
Reduce workload
Improve pump function
How many stages of heart disease are there?
4 stages - A-D with B1 and B2 as sub-stages
What is stage B2 heart disease?
Asymptomatic with cardiac remodelling
What is stage C of heart disease?
Clinical signs of congestive heart failure
What is the action of diuretics?
To remove fluid from the body and control oedema
What are the 3 types of diuretics?
Loop - Furosemide/Torsemide
Potassium Sparing - Spironolactone (cats)/ Amiloride
Thiazide
What is the action of ACE inhibitors?
Dilate arteries, veins or both.
What is the common presentation of a stage D heart disease patient?
Coughing, dyspnoea, cyanotic, coughing up fluid and a raised chest
What is the main clinical signs of feline thromboembolic disease?
Paralysis of the back legs
Lameness
Extreme pain
What are the 4 types of primary myocardial disease?
- Dilated cardiomyopathy (DCM)
- Arrhythmogenic right ventricular cardiomyopathy (ARVC)
- Hypertrophic cardiomyopathy (cats)
- Restrictive cardiomyopathy (cats)
What are the 3 types of secondary myocardial disease?
- Infective myocarditis
- Deficiency diseases
- Toxic causes
What are the characteristics of dilated cardiomyopathy?
Impaired myocardial contraction with dilation of the left ventricle +/- right ventricle
What signalment is important with DCM?
Breed - Doberman, Newfoundland, Cocker Spaniel, Labs, Great Dane, Boxers, GSD
Age - usually middle aged
Size - over 12kg
Gender - males typically more severe
What are the clinical signs of DCM?
CHF, syncope, weight loss, sudden death, soft murmur, A-fib
What is the pathophysiology of boxer cardiomyopathy?
Myofibre atrophy, fibrosis and fatty infiltration.
What is hypertrophic cardiomyopathy?
Inappropriate myocardial hypertrophy of a non-dilated LV. Can be obstructive and non obstructive.
What is the pathophysiology of restrictive cardiomyopathy?
Atrial enlargement, extensive fibrosis, mild LV hypertrophy, diastolic failure
What sedation should be used for a cat with heart failure?
Butorphanol as there is no negative respiratory effect.
What is the function of the pericardial sac?
Prevents distension of the heart into the chest cavity and reduces friction of the heart.
What is cardiac tamponade?
Increased pressure around the heart
What are clinical signs of pericardial disease?
Jugular distension
Positive hepatojugular reflex
Ascites
Tachycardia/tachypnoea/dyspnoea
Muffled heart sounds
Weak femoral pulses/ pale MMs
GIT signs
What does radiography show with pericardial disease?
Globoid enlargement of the cardiac silhouette with a sharp outline.
List the causes of pericardial effusion in dogs
Cardiac neoplasia
Idiopathic
Left atrial rupture
Coagulopathies
Uremic
Infection
List the causes of pericardial effusion in cats
Congestive heart failure
Feline infectious peritonitis
What are the three types of cardiac neoplasia?
- Hemangiosarcoma
- Heart base tumours
- Mesotheliomas
What are the causes of constrictive pericardial disease?
Long-term pericardial effusion complication
Repeated pericardiocentesis
Idiopathic
What occurs in haemostasis?
Primary - Platelet plugs
Secondary - Fibrin plug requiring coagulation cascade
Clot lysis
What four components make a clot?
- Cells
- Proteins
- Facilitators
- Physiologic inhibitors
What is thrombocytopaenia?
Low platelet numbers
What is thrompocytopathia?
Platelet dysfunction
What are the causes of thrombocytopaenia?
Defective platelet production
Accelerated platelet removal
Platelet sequestration or loss
How do you diagnose thrombocytopathia?
Normal PLT count but prolonged BMBT
Normal levels of vWF
Diagnosis of exclusion
Platelet function test
What are the clinical signs of von Willebrand’s disease?
Mucosal haemorrhage, cutaneous bruising, prolonged bleeding
What marker is increased in a pro-thrombotic state?
D-dimer
What is disseminated intravascular coagulation (DIC)?
Excessive activation of haemostatic pathways causing haemorrhage
What can trigger disseminated intravascular coagulation (DIC)?
Endothelial damage
Platelet activation
Release of tissue procoagulants
