Congenital heart disease (Yr 4)

Question 1

what are the differentials for heart murmurs in puppies/kittens?

Answer 1

innocent “flow” murmur
anaemia (fleas…)
congenital heart disease

Question 2

where does a patent ductus arteriosus run?

Answer 2

from descending aorta into pulmonary artery

Question 3

how does the patent ductus arteriosus effect the heart?

Answer 3

causes left sided volume overload as blood flows from the aorta into the pulmonary artery and back into the left atrium

Question 4

does the murmur associated with patent ductus arteriosus occur in systole or diastole?

Answer 4

continuous (pressure in aorta is always greater than the pulmonary artery)

Question 5

what effect can volume overload of the left side of the heart due to patent ductus arteriosus have?

Answer 5

dilation of mitral valve annulus leading to mitral regurgitation
left sided heart failure

Question 6

how does the femoral pulse of patent ductus arteriosus cases feel?

Answer 6

like tapping/waterhammer (continues blood moving into pulmonary circulation)

Question 7

what is the most likely cause of a continuous murmur?

Answer 7

patent ductus arteriosus

Question 8

what is the only congenital heart defect to have a sex predisposition?

Answer 8

patent ductus arteriosus (bitches more commonly effected)

Question 9

what breeds is patent ductus arteriosus usually seen in?

Answer 9

German shepherds
collies
bichon frise, poodles…
cavalier King Charles spaniel

Question 10

is patent ductus arteriosus more common in cats or dogs?

Answer 10

dogs (rare in cats)

Question 11

how will a puppy with patent ductus arteriosus present?

Answer 11

initially asymptomatic (no stunting…)
murmur can be very localised initially

Question 12

where is a patent ductus arteriosus murmur localised to?

Answer 12

left axilla

Question 13

can patent ductus arteriosus be treated?

Answer 13

yes

Question 14

what are the radiographic findings of patent ductus arteriosus?

Answer 14

left atrial/ventricle enlargement
“triple knuckle” on dorsoventral view

Question 15

what causes the “triple knuckle” appearance of patent ductus arteriosus?

Answer 15

aortic, pulmonary artery and left atrial appendage

Question 16

how will ECGs appear with patent ductus arteriosus?

Answer 16

really tall R waves - evidence of left ventricular enlargement
wide bifold P wave (P mitrale) - evidence of left atrial enlargement)

Question 17

how can patent ductus arteriosus be treated?

Answer 17

surgery (thoracotomy and ligation of ductus)
catheterisation based occlusion of PDA (femoral artery/vein)

Question 18

what happens to the left ventricle in cases of (sub)aortic stenosis?

Answer 18

pressure overload leading to concentric hypertrophy

Question 19

what breeds is (sub)aortic stenosis seen in?

Answer 19

boxers
newfoundlands
golden retrievers
rottweillers
bull terriers

Question 20

is (sub)aortic stenosis more common in dogs or cats?

Answer 20

dogs (uncommon with poor prognosis in cats)

Question 21

why does (sub)aortic stenosis cause concentric hypertrophy?

Answer 21

there is increased afterload (pressure) on the left ventricle

Question 22

why can concentric hypertrophy effect coronary circulation?

Answer 22

perfusion is compromised due to squashing of the coronary vessels and also the vessels not being able to keep up with the rate of hypertrophy

Question 23

why is myocardial ischaemia a big risk in (sub)aortic stenosis?

Answer 23

(sub)aortic stenosis causes concentric hypertrophy which can squash coronary vessels and the rate of hypertrophy can be too fast so the vessels are unable to keep up

Question 24

how would you describe a (sub)aortic stenosis murmur?

Answer 24

harsh mid/holosystolic murmur that radiates up the carotids on the right chest

Question 25

how can femoral pulses be effected by (sub)aortic stenosis?

Answer 25

with severe stenosis there can be weak pulses

Question 26

what two breeds have the highest predisposition to (sub)aortic stenosis?

Answer 26

boxers newfoundlands

Question 27

what is the treatment for (sub)aortic stenosis?

Answer 27

no surgical treatment available

Question 28

what treatment should be avoided in (sub)aortic stenosis cases?

Answer 28

positive inotropes (pimobendan) or arteriodilators

Question 29

what effect does pulmonic stenosis have on the right ventricle?

Answer 29

concentric hypertrophy due to pressure overload

Question 30

what breeds is pulmonic stenosis mainly seen in?

Answer 30

cocker spaniels cavalier King Charles spaniel terriers beagles bull mastiff boxer

Question 31

how do dogs with pulmonic stenosis present?

Answer 31

initial asymptomatic heart murmur develop syncope and exercise intolerance

Question 32

how is the murmur associated with pulmonic stenosis described?

Answer 32

mid/holosystolic murmur cranially on the left heart base that radiates dorsally

Question 33

what are the pathophysiological consequences of pulmonic stenosis?

Answer 33

increased afterload of right ventricle causes right ventricular hypertrophy which can lead to myocardial ischamia

Question 34

what effect does very severe pulmonic stenosis have on the septum?

Answer 34

the pressure in the right ventricle can increase to more than the left changing the motion of the septum

Question 35

what radiographic changes are seen with pulmonic stenosis?

Answer 35

more sternal contact due to increased size of the right of the heart bulging pulmonary artery (at 2 o'clock)

Question 36

how does pulmonic stenosis present on an ECG?

Answer 36

negative QRS in lead one (right axis deviation as there is greater muscle mass on right)

Question 37

how can pulmonic stenosis be treated?

Answer 37

surgical (dilate pulmonic annulus) balloon valvuloplasty

Question 38

where does blood move from and too in ventricular septal defects?

Answer 38

from left to right ventricle

Question 39

what breeds is ventricular septal defect most common in?

Answer 39

cocker spaniel west highland white terrier

Question 40

how does the grade of murmur in ventricular septal defects correlate to severity of disease?

Answer 40

inversely (the louder the murmur the less severe the disease is)

Question 41

why is the grade of murmur inversely correlated to the severity of disease in ventricular septal defects?

Answer 41

small defects maintain the pressure gradient between left and right ventricular leading to a very fast turbulent blood flow creating a loud murmur

Question 42

how would a murmur associated with ventricular septal defects be described?

Answer 42

systolic murmur with PMI on the right

Question 43

what is the pathophysiology associated with ventricular septal defects?

Answer 43

left to right shunt leading to volume overload of right ventricle and pulmonary over circulation causing a volume overload of the left atrium/ventricle which can cause left sided heart failure

Question 44

what are some possible sequelae to ventricular septal defects?

Answer 44

close with growth aortic valve leaflets may prolapse and aortic regurgitation can develop pulmonary hypertension can result in high right ventricular pressure leading to a shunt reversal (right to left)

Question 45

what breeds are predisposed to mitral dysplasia?

Answer 45

bull terriers golden retrievers great danes German shepherds

Question 46

what breeds are predisposed to tricuspid dysplasia?

Answer 46

labradors

Question 47

what is the main consequence of mitral/tricuspid valve dysplasia?

Answer 47

regurgitation

Question 48

what are the pathophysiological features of mitral/tricuspid valve dysplasia?

Answer 48

regurgitation leading to volume overload and possible left/right sided heart failure (possible arrhythmias)

Question 49

which was do shunts occur in atrial septal defects?

Answer 49

left to right (not a massive pressure gradient)

Question 50

do murmurs occur in atrial septal defects?

Answer 50

not always - pressure gradient is low so little movement and turbulence is created

Question 51

what are the four defects in the tetralogy of fallot?

Answer 51

pulmonic stenosis right ventricular hypertrophy ventricular septal defect dextroposed aorta

Question 52

what are some congenital cardiovascular abnormalities that can present without a murmur?

Answer 52

vascular ring anomalies (persistent right aortic arch) peritoneopericardial diaphragmatic hernia

Question 53

what does a persistent right fourth aortic arch cause?

Answer 53

megaoesophagus (structure of the oesophagus)