Cardio Ii - Congenital Defects

Front 1

What is the difference in O2 saturation in the left and right ventricles?

Back 1

Left - 98-99%
Right - 70%

Front 2

What can you learn about heart defects from O2 saturation measurements?

Back 2

1. see mixing of blood - change in O2 saturation
2. can calculate amount of shunting

Front 3

How can you tell you are looking at the RV on an angiogram?

Back 3

Trabeculated appearance at apex

Front 4

What part of the heart appears "bullet-shaped" on an angiogram?

Back 4

LV

Front 5

What are two arteries you can use to gain access to the left ventricle?

Back 5

1. Carotid
2. Femoral

Front 6

What are top 2 congenital defects in dogs?

Back 6

1. PDA
2. ToF

Front 7

What two vessels are connected with a PDA?

Back 7

aorta and main pulmonary artery

Front 8

What change in O2 tension do you have with PDA?

Back 8

Step up in O2 tension in MPA

Front 9

What parts of the heart are affected by a PDA?

Back 9

Left side - volume overload in pulmonary circulation, LA, LV, Aorta +/- right side if PA pressure rises and causes pressure overload

Front 10

What is the sex predisposition for PDA?

Back 10

Female

Front 11

What is the classic finding for PDA in physical exam? Where do you listen?

Back 11

Continous murmur at the left heart base - axilla (need to make sure you get all the way up into the armpit)
+/- systolic murmur of mitral regurgitation at the left apex

Front 12

Why will you have bounding arterial pulses in PDA?

Back 12

large stroke volume from diastolic run off through the PDA

Front 13

What abnormalities do you see on an EKG with PDA?

Back 13

LVE pattern > 3.0mV lead II
P-mitrale
VPC, APC, atrial fibrillation, ventricular tachycardia

Front 14

What are classic radiographic findings for PDA?

Back 14

3 bumps
1. aorta
2. MPA
3.LAA

Front 15

What anatomical changes result from pulmonic stenosis?

Back 15

RV - concentric hypertrophy
post stenotic dilation of pulmonary artery
Secondary tricuspid regurgitation

Front 16

What clinical signs would make you think of pulmonic stenosis?

Back 16

Systolic ejection murmur
Apex beat strongest at right hemithorax
Syncope
RCHF - abdominal distention, ascites, tachypnea

Front 17

What will you hear with pulmonic stenosis?

Back 17

ejection systolic murmur at left heart base - 2-4 interspace
Second murmur can be heart at tricuspid on right mid cardiac region

Front 18

What does pulmonic stenosis look like on a radiograph?

Back 18

RVE
+/- pulmonary artery segment bulge
+/- enlargement of RA and cava
apparent hypovascularity

Front 19

When using continous doppler ultrasound what pressure would you see for mild, moderate or severe pulmonic stenosis?

Back 19

Mild < 50 mmHg
Moderate 50-100 mmHg
Severe > 100 mmHg

Front 20

What does an echo look like for pulmonic stenosis?

Back 20

RVE concentric hypertrophy
Valvular or subvalvular pulmonic stenosis w/ turbulent flow

Front 21

What is the treatment for pulmonic stenosis? What is the goal?

Back 21

Balloon valvuloplasty
> 50% reduction in doppler gradient
Residual gradient < 100 mmHg

Front 22

What are the top 3 dog defects?

Back 22

1. PDA
2. Pulmonic stenosis
3. Aortic stenosis

Front 23

What is the cause of aortic stenosis?

Back 23

Big thick fibrous tissue underneath aortic valve - narrowed aortic outflow tract

Front 24

What anatomic changes take place as a result of aortic stenosis?

Back 24

concentric LVE
post-stenoic dilation of aorta +/- jet lesion
Mild aortic regurgitation

Front 25

What type of aortic stenosis is most common in cats?

Back 25

supravalvular AS

Front 26

What are clinical signs that direct you toward aortic stenosis?

Back 26

Asymptomatic
Syncope
Bacterial endocarditis
LCHF
Sudden death - may be 1st thing you see

Front 27

What physical exam abnormalities do you see with aortic stenosis?

Back 27

Systolic ejection murmur at left heart base 3-4th space
Weak arterial pulses
prominent left apical impulse

Front 28

How does an ECG change with aortic stenosis?

Back 28

LVE
ST segment depression - if you see this the dog is about to have major problems from this defect

Front 29

What do you see on a radiograph for aortic stenosis?

Back 29

Concentric LVE may not be visible
Prominent aorta cranial to heart - enlarges as dog ages

Front 30

What are the pressure gradients you will see for mild, moderate and severe aortic stenosis with continous doppler ultrasound?

Back 30

Mild < 40 mmHg
Moderate 40-80 mmHg
Severe > 80 mmHg

Front 31

Is there a cure to fix aortic stenosis?

Back 31

No, balloon valvuloplasty is most common but has inconsistent pressure reduction
Atenolol - beta blocker - no proof of efficacy

Front 32

Why is sudden death so common with aortic stenosis?

Back 32

Muscle around the coronary arteries will be high during systole - this causes the vessels to collapse and generates retrograde flow
As the HR increases the periods of diastole decrease this can lead to ventricular arrhythmia - death results

Front 33

What anatomical changes are present with VSD?

Back 33

Communication between right and left ventricle - left to right blood flow
Usually high in IVS
May results in LAE or LVE
RE more variable - depends on defect size and location

Front 34

What is the most common heart defect in horses, ruminants and maybe cats?

Back 34

VSD

Front 35

What is the difference in CHF that develops from VSD in dogs and cats?

Back 35

Dogs - pulmonary edema
Cats - pulmonary edema and pleural effusion (difference in lymphatics)

Front 36

What physical exam abnormalities do you find with VSD?

Back 36

Systolic murmur - variable (holosystolic)
Loudest at right sternal border
Second murmur of pulmonic stenosis at left heart base
Arterial pulses are brisk w/ large defect, weak if CHF

Front 37

What are the abnormalities noted on a radiograph of VSD?

Back 37

Left heart of generalized cardiac enlargement
Pulmonary overcirculation
CHF may be present

Front 38

How does the size of VSD affect clinical findings?

Back 38

Small VSD - limited clinical importance, breeding consideration
Large - CHF

Front 39

What test do you use to determine severity of VSD?

Back 39

Continous flow Ultrasounds
Pulmonary to systemic blood flow ratio Qp:Qs > 2.5 then problems are more likely

Front 40

What are treatment options for VSD?

Back 40

Pulmonary artery banding
Surgical repair - cardiopulmonary bypass, patch over VSD
VSD amplatz occluder - only works if in the middle of IVS - otherwise can trap valves

Front 41

What are two different types of atrial septal defects?

Back 41

1. Ostium primum defect - low in atrial septum
2. Ostium secundum defect - middle (high) in atrial septum

Front 42

What anatomical changes do you see with ASD?

Back 42

Blood flows left to right
Pulmonary overcirculation
Right heart enlargement

Front 43

Why do you have a murmur in ASD?

Back 43

NOT from flow through ASD
Fixed splitting of second heart sound - always takes longer for Right to move blood - Pulmonic valve closure always after aortic valve closure
Relative tricuspid stenosis
Relative pulmonic stenosis

Front 44

What is the most common defect in cats (maybe)?

Back 44

AV valve dysplasia

Front 45

What anatomical changes are associated with AV valve dysplasia?

Back 45

Thickened or fused leaflets
Abnormal chordae tendinae (short or long)
Abnormal papillary muscles - malposition, incomplete or absent, abnormal attachment to ventricular wall

Front 46

What anatomical changes are associated with ToF (4 parts)?

Back 46

1. VSD
2. Pulmonic stenosis
3. Dextropositioned overriding aorta (over both LV and RV)
4. Secondary RVE

Front 47

What abnormal tests do you see with ToF? (Physical exam, ECG, Rads)

Back 47

PE - cyanosis, murmur at right cranial sternal border, left heart base (PS)
ECG - RVE pattern
Rads - undercirculation

Front 48

What are anatomical and clinical findings with R to L VSD?

Back 48

Anatomical - large VSD, pulmonary hypertension, R to L or bidirectional shunting
Clinical - cyanosis, variable murmurs, polycythemia

Front 49

What anatomical and clinical signs do you see with PDA w/ pulmonary hypertension?

Back 49

Anatomical - pulmonary pressure equal aortic, R to L shunting at ductus, concentric hypertrophy of RV
Clinical - differential cyanosis, continous murmur diappears, loud second heard sound at heart base

Front 50

What treatment is contraindicated for R to L PDA?

Back 50

Surgery - DO NOT do it