Cardiology Flashcards
Define heart failure:
Heart disease which is severe enough to overwhelm the compensatory mechanisms of the cardiovascular system
Which is a good vein to check for venous pressure and how might you do it?
The jugular - lift the liver to increase the pressure at the back of the dog and watch the jugular pulses.
Which disease makes up 80% of all canine cardiac disease?
Chronic valvular heart disease (mainly mitral)
What type of heart disease are large dogs particularly prone to?
Cardiomyopathies.
What is the predominant heart disease found in cats?
Cardiomyopathies (mainly hypertrophic).
What is a haemic murmur and in what age group are you likely to see it?
See in puppies and kittens - they have a lower haematocrit than adults, therefore their blood is less viscous and breaks into turbulence at lower velocity.
Is it possible to induce a murmur in a small animal?
Yes, by putting too much pressure on the chest during examination.
Does increased tallness of the heart tell us more about the left or right side?
The left.
What form does canine cardiomyopathy usually take?
Dilated
What is stage A heart disease?
Patient that is at high risk of developing heart disease but does not yet actually have any (a healthy Cavalier King Charles)
What is stage B heart disease?
Patient has evidence of structural heart disease but no clinical signs of heart failure.
What is stage C heart disease?
Patient with past or current clinical signs of heart failure associated with structural heart disease.
What is stage D heart disease?
Patient with end stage cardiac disease - clinical signs of heart failure are refractory to ‘standard therapy’.
How would you describe the appearance of the nodule in chronic valvular heart disease?
Smooth, rounded, firm nodules.
Chronic valvular heart disease leads to “valvular ______”
Insufficiency / regurgitation / leakage
Volume overload in the heart leads to what type of hypertrophy?
Eccentric hypertrophy
Pressure overload in the heart leads to what type of hypertrophy?
Concentric hypertrophy
True or false:
Enlargement and damage to the heart makes spontaneous depolarisations more likely?
True
What changes do you see in sympathetic and parasympathetic tone in chronic valvular heart disease?
Increased sympathetic tome and decreased parasympathetic tone.
In what type of heart failure might pleural effusion be seen?
Biventricular failure.
Mitral regurgitation and developing left heart failure could predispose to right heart failure, especially if there were the beginnings of degenerative lesions on the tricuspid valve. How?
Left heart failure causes more pressure in the lungs and therefore the right side now has to work harder.
Will you hear sinus arrhythmia with tachycardia?
No - an irregularity associated with a fast heart rate is likely to be pathological.
Which part of the cardiac cycle is diastole?
Relaxation - heart refilling with blood.
Which part of the cardiac cycle is systole?
Contraction - heart is emptying.
What does increased diastolic pressure do to pulse strength?
Decreases pulse strength
What is the most common scenario in which you will hear a gallop sound?
In a cat with hypertrophic cardiomyopathy
What happens if you give frusemide on its own? What should it be given with?
It will active RASS - you should give it with an ace inhibitor.
What should you do one week after starting an animal on ACEI?
Check that the drug has not raised serum creatinine substantially.
What is the effect of nitroglycerine ointment?
Vasodilator
Whic main location do septic emboli from infective edocarditis travel to?
The kidneys and cause infarcts
What is the pathological consequence of immune complexes formed in infective endocarditis?
Lodge in basement membranes in various locations and set up inflammatory responses - joints (polyarthritis) and glomeruli (leakage of albumin).
What is the incidence of infective endocarditis?
Uncommon to rare in dogs. Very rare in cats.
What is a prerequisite of infective endocarditis?
Blood-borne infection.
What are the most common bacteria found in cases of infective endocarditis?
Staphylococcus, streptococcus, E. coli, pseudomonas aeruginosa.
What antibiotic classes wou;d be best indicated for treatment of infective endocarditis?
beta lactam + aminoglycoside combination OR a fluoroquinolone
Why might a murmur caused by cardiomyopathy in a dog be quite soft?
The murmur is softer due to weaker muscle contractions.
Treatment principles for canine cardiomyopathies:
A diuretic to relieve congestion.
A positive inotrope to support ventricular function.
An ACEI to oppose RAAS, reduce salt and water retention and mildly vasodilate.
Anti-arrhhythmic drugs as necessary.
What is the first sign of digoxin toxicity?
Anorexia / vomiting
What is the most common presentation of cardiomyopathy in cats?
Hypertrophic
What is a common sequela of hypertrophic cardiomyopathy in cats?
Caudal aortic saddle thrombus
Do you perform thoracocentesis in front of or behind the rib?
In front of the rib
Why might you sedate an animal in acute congestive heaart failure?
To calm them down which can improve the efficacy of breathing.
What is the most common congenital cardiovascular defect in dogs?
Patent ductus arteriosus
What is differential cyanosis and when will you see it?
Patent ductus arteriosus with right to left (reversed) shunt causes differential cyanosis. The gums are receiving fully oxygenated blood so they are pink but the vulval/prepuce mucous membranes will be purple due to deoxygenated blood mixing in the aorta.
What 4 things make up ‘Tetralogy of Fallot’?
- Pulmonic stenosis
- Secondary right ventricular hypertrophy
- Ventricular septal defect
- Overriding aorta
