8/18- Congenital Heart Disease Flashcards Preview

_MS2 Cardio > 8/18- Congenital Heart Disease > Flashcards

Flashcards in 8/18- Congenital Heart Disease Deck (45):
1

A child with cyanotic heart disease most likely has a heart defect that shunts?

A. Right to left

B. Left to right

A child with cyanotic heart disease most likely has a heart defect that shunts?

A. Right to left

B. Left to right

2

Which of the following patients is most likely to have irreversible pulmonary hypertension?

A. A 10 yo with tetrology of Fallot

B. A 1 yo with muscular VSD

C. A 10 yo with truncus arteriosus

D. A 10 yo with ASD

Which of the following patients is most likely to have irreversible pulmonary hypertension?

A. A 10 yo with tetrology of Fallot

B. A 1 yo with muscular VSD

C. A 10 yo with truncus arteriosus

D. A 10 yo with ASD

3

Epidemiology of Congenital Heart Disease

- Child

- Adult

Child

- Most common heart disease

- May become symptomatic with transitional circulation

- Most repaired in childhood--but sequelae

Adult

- >85% childhood CHD become adults

- More adults with CHD than children (repaired lesions)

- Most cardiologosits trained in CHD are pediatric...

Short and long term sequelae require care

4

What is the definition of congenital heart disease?

Non-heart structures affected?

- Structural malformations

- Present at birth

- Result from abnormal embryogenesis (3-8 wks gestation)

Associated extracardiac anomalies: 16-39%

5

What is a shunt (basic def)?

Abnormal communication between systemic and pulmonary circulation

6

In a shunt, the direction and amount of blood flow is determined by what factors?

- Size of defect

- Vascular resistance

- Pressure gradient

- Distensibility of chambers

7

Clinical consequences of a shunt?

- Increased blood flow in one circulation; decreased in the other

- Decreased oxygen in systemic circulation

8

What is cyanosis (def)?

Arterial O2 desaturation with > 3-5 gm/dL of unsaturated Hb

- Blue discoloration of nailbeds and mucus membranes

- Clubbing: convexity of nailbed +/- expansion of distal end of digit

9

Functional classifications of shunts? Examples?

1. Left to right shunt (systemic -> pulmonary)

- ASD

- VSD

- PDA

2. Right to left shunt (pulmonary -> systemic)

- Tetrology of Fallot

- TV atresia

- Truncus arteriosus

- TAPVC

- TGA

- HLHS

3. Obstructions

- Coarction of aorta

- Valve stenosis or atresia

- Subvalve or supravalve stenosis

10

Functional consequences due to changes in what factors?

- Oxygen saturation

- Blood volume

- Blood pressure

 Ultimate effects on tissue perfusion

11

Evaluation of pts with CHD

Physical exam:

- Murmurs, thrills, heart sounds, pulses/BP/ cyanosis (upper and lower extremity differences)

CXR

ECG

Labs:

- Arterial blood gas

- Lactate

Diagnostic

- Echocardiogram

- Cardiac cath

- Cardiac MRI

- CT angiography

12

What are the left to right shunts?

- ASD

- VSD

- PDA

13

Characteristics of left to right shunts?

- Increased pulmonary blood flow

- Decreased systemic CO

- No direct effect on oxygenation

-> Pulmonary edema

-> Congestive Heart Failure

14

What are the 3 major types of atrial septal defects? What percentage of all CHD do these comprise?

ASD are 10% of all congenital heart defects 3 major types:

1. Secundum

2. Primum

3. Sinus venosus 

A image thumb
15

Which ASD is the most common?

Secundum (90%)

16

What causes secundum ASD/where does it occur?

Valve of foramen ovale (septum primum) not well developed

- usually an isolated lesion

A image thumb
17

What are the consequences/effects of ASD?

- Increased RA and RV preload -> dilation

- Increased pulmonary bloodflow (but not pressure)

- High RV compliance

- Slow increase in PA pressure

Usually asymptomatic until ~age 30

- Pulmonary HTN

- RV heart failure

Large ASD:

- Early heart failure 

A image thumb
18

Treatment of ASD?

Repair

- ASD closure device or patch

A image thumb
19

VSDs are responsible for __% of all CHDs

VSDs are responsible for 40% of all CHDs

20

What are the 3 major types of VSD? Which is the most common?

1. Membranous (perimembranous)

2. Infundibular (conal septal)

3. Muscular Peri/Membranous is the most common (90%)

A image thumb
21

What is this?

Q image thumb

Membranous ventricular septum (light shining through)

22

What is this? 

Q image thumb

Perimembranous VSD

23

What are the consequences/effects of VSD?

- Increased pulmonary blood flow AND pressure

- Increased LV preload/volume

- Decreased CO

-> Pulmonary edema

-> Congestive Heart Failure (left sided! volume load on left side)

Size affects symptoms!

Symptom onset often with drop in neonatal pulmonary vascular resistance 

A image thumb
24

Spontaneous closure of perimembranous VSD may be due to what? Muscular VSD?

Perimembranous VSD: adherence of TV

Muscular VSD: growth of heart muscle

25

What is shown here on the left? right? 

Q image thumb

Left: perimembranous VSD (clsoed by TV adherence)

Right: muscular VSD (closed by heart muscle growth)

26

How is VSD treated? When to treat?

- May close spontaneously

- Usually patch closure if no spontaneous closure

When considering repair, think of:

- Likelihood of spontaneous closure (usually before 5 yo)

- Severity of clinical Sx (may correlate with size of defect)

- Risk of irreversible pulmonary HTN (unusual before 2 yo)

27

What are the long term sequelae for patching a VSD?

- Infective endocarditis (prosthetic patch)

- Patch dehiscence

- Arrhythmias

28

What is the "dreaded" complication for a left to right shunting lesion?

Pulmonary HTN and shunt reversal

- Uncontrolled, persistent increased pulmonary pressure/resistance will reverse the direction of a left to right shunt

-> Late onset cyanosis

Irreversible pulmonary HTN is the dreaded complication of a L to R shunt

- Once it develops, repair of defect is not indicated 

A image thumb
29

What are CHDs of Right to Left shunt?

How may they be divided?

Decreased pulmonary bloodflow (more common):

- Tetralogy of Fallot (TOF)

- TV atresia

Increased pulmonary bloodflow:

- Truncus arteriosus

- TAPVC

- TGA

- HLHS

30

Characteristics of right to left shunts with decreased pulmonary blood flow?

(Decreased pulmonary bloodflow)

Associated with:

- R sided obstruction distal to shunt (e.g decreased pulmonary outflow tract), OR

- Elevated pulmonary pressure

Desaturated venous blood enters systemic circulation

- > cyanotic congenital heart disease

-> poor tissue oxygenation

31

What is the Tetaralogy of Fallot (TOF)?

Malaligned outflow tract septum resulting in:

- SubPA (RVOT) stenosis

- VSD

- Aortic over-ride of VSD

- RV hypertrophy

Stenosis severity determines direction of magnitude and shunt

A image thumb
32

What is this? 

Q image thumb

Tetralogy of Fallot 

A image thumb
33

Physiology (consequences) of TOF?

- Increased RV preload/volume

- Increased afterload/pressure -> RV dilated and hypertrophied (more blood going into aorta; more returning to right A/V -> R sided failure)

- PA is small (hypoblastic)

- Aorta s dilated

A image thumb
34

What are the systemic consequences of TOF?

Poor tissue oxygenation

- Hypoxemia and polycythemia

- Cyanosis that worsens with exercise

- Clubbing after 3 mo of age

Paroxysmal hypoxia

- RVOT spasms

- (TET spells)

35

How is TOF treated?

Surgical repair: as early as feasible

- Improve tissue perfusion

- Decrease risk of post-operative arrhythmias

Common follow-up = valve replacement before pulmonary regurg causes permanent problems with volume load on _ventricle

36

What is the most common form of cyanotic congenital heard disease?

Tetralogy of Fallot (TOF)

37

TOF is responsible for __% of congenital heart disease?

TOF is responsible for 5% of congenital heart disease?

38

What is the current survival rate of TOF?

> 75-80% 30 yrs

TOF is one of the most common anomalies seen in adult with congenital heart disease

39

What is TV atresia? Characteristics? Consequences?

CHD that involves a right to left shunt and decreased pulmonary blood flow

- Obligate RA -> LA shunt at atrial septum (no communication between R heart and pulmonary artery?)

- Increased LA and LV volume

- Pulmonary blood flow is dependent on VSD usually decreased

-> cyanotic CHD 

A image thumb
40

What is truncus arteriosus? Characteristics? Consequences?

CHD that involves a right to left shunt and increased pulmonary blood flow

- Due to failure of embryonic truncus and usually outflow tract of heart to develop a septum

- Single great artery gives rise to aorta, pulmonary, and coronary arteries

- Single semilunar (truncal) valve that may be stenotic or regurgitant

Consequences:

- Variably increased pulmonary bloodflow

- High risk for pulmonary HTN

-> cyanotic CHD) 

A image thumb
41

What is TAPVC?

Total anomalous pulmonary venous connection

- Obligate right -> left shunt at atrial septum

- Pulmonary veins don't connect to LA

May connect to various sites:

- Most common = innominate vein

Consequences:

- Increased RA and RV volume

- Increased pulmonary bloodflow -> cyanotic CHD 

A image thumb
42

Most obstructive lesions are ___

Most obstructive lesions are valvular

43

Physiology (characteristics) of obstructive lesions?

- High pressure proximal to obstruction

- Decreased bloodflow distal to obstruction

44

What is shown here? 

Q image thumb

Obstructive lesion: aortic valve stenosis

45

Treatment for obstructive lesions?

- Balloon repair

- Valve replacement