Congenital heart disease Flashcards
What is congenital heart disease
malformations of the heart and great vessels that occur due to altered or arrested embryonic development
many animals are asymptomatic when first examined
Describe an innocent murmur
low grade 1-2
murmur loudest= left heart base
varying intensity with heart rate
usually resolve by 6 months (exception some large breeds)
What is the only way you can assess the nature and severity of a murmur
full doppler echocardiogram
If you hear a <grade 2 murmur in a puppy what to do
could be innocent
re-assess at 3 and 6 months
need to warn owners
if you hear a loud (grade 3+) murmur in a puppy what should you do
more likely to be a congenital anomaly
more likely to want to scan these
List the 4 most common types of congenital heart disease
Aortic stenosis
patent ductus arteriosus
pulmonic stenosis
ventricular septal defect
Describe Aortic stenosis
= narrowing of the aorta
3 types
what is the most common type of aortic stenosis
sub-aortic stenosis
describe sub-aortic stenosis
Sub valvular narrowing caused by a fibrous or fibromuscular ring
Can increase in severity as dog matures reaching maximum severity at 1-2 years of age
Exercise / excitement can cause an increase in the intensity of the murmur
What breed are you most likely to see sub-aortic stenosis in
Boxers
Newfoundlands
Golden Retrievers
Describe the sound caused by aortic stenosis
harsh systolic ejection murmur
murmur loudest= aortic valve
describe the historical and clinical findings you would see in a case of aortic stenosis
historical- vary from none to syncope (fainting)
Lethargy, exertional weakness, syncope, sudden death
How many types of pulmonary stenosis are there and which is the most common
5 types
valvular pulmonic stenosis
what breed do you tend to see pulmonic stenosis in
usually smaller breed dogs
terriers, bulldogs
how to pulmonic stenosis cases present
many asymptomatic
clinical signs depend on severity
right sided heart failure, syncope, exercise intolerance
Describe the murmur you would hear with a pulmonic stenosis
High frequency systolic ejection murmur
prominent right apical beat
murmur loudest= left heart base
prominent jugular pulses
Describe a patent ductus arteriosus
blood shunting from aorta into pulmonary artery
continuous murmur
Best heart over left heart base but very cranial and dorsal (in axilla)
Very important to detect as potentially curable
What happens if you don’t fix a patent ductus arteriosus
After 12 months many dogs will progress into left sided congestive heart failure adn show typical clinical signs
How do you treat PDA
surgical- ligate it
Occluder- placed through cannula in femoral artery
Where do ventricular septal defects occur
high in the membranous part of the septum just below the aortic valve and under the tricuspid leaflet
Describe a how a ventricular septal defect sounds
small defects (which are clinically unimportant) cause a very loud murmur
large defects- very quiet
systolic murmur loudest over cranial right sternal border
