Mod VI: Congenital Heart Disease

Question 1

_{Congenital Heart Disease}

Congenital Heart Diseases are present in about what percentage of newborn infants?

Answer 1

1%

Question 2

_{Congenital Heart Disease}

What are the causes of Congenital Heart Disease?

Answer 2

Idiopathic

Genetic

Environmental

^{(rubella 1st trimester, lithium, FAS)}

Question 3

_{Congenital Heart Disease}

What are risk factors for Congenital Heart Disease?

Answer 3

Parent with CHD

Prematurity

Multiple gestations

Noncardiac congenital anomalies (Down’s syndrome)

Question 4

_{Congenital Heart Disease}

Signs & Symptoms of Congenital Heart Disease in infants are:

Answer 4

Tachypnea

Failure to gain weight

Tachycardia (>200)

Heart murmur

Congestive heart failure

Hypoxemia

Cyanosis

Question 5

_{Congenital Heart Disease}

Signs & Symptoms of Congenital Heart Disease in children are:

Answer 5

Dyspnea

Failure to grow

Decreased exercise tolerance

Heart murmur

Congestive Heart Failure

Cyanosis

Clubbing of digits

Squatting (To increase SVR)

HTN

Chest pain

Question 6

_{Congenital Heart Disease}

T/F: Most Congenital Heart Diseases are diagnosed prior to birth

Answer 6

True

Question 7

_{Congenital Heart Disease - Diagnosis}

T/F: Congenital Heart Disease is apparent during first week of life in 50% of afflicted neonates and before 5yrs in all remaining

Answer 7

True

Question 8

_{Congenital Heart Disease - Diagnosis}

What’s the initial diagnostic test recommended for CHD?

Answer 8

US Echocardiography

Question 9

_{Congenital Heart Disease - Diagnosis}

Test that demonstrates valvular dysfunction and septal defects

Answer 9

Doppler US

Question 10

_{Congenital Heart Disease - Diagnosis}

Tests that demonstrate anomalies involving great vessels

Answer 10

CT scan - MRI

Question 11

_{Congenital Heart Disease - Diagnosis}

What’s the most definitive diagnostic technique for CHD?

Answer 11

Cardiac catherization

Question 12

_{Congenital Heart Disease}

Problems afflicting patients with Congenital Heart Disease include:

Answer 12

Pulmonary vascular disease & associated PHTN

Congestive heart failure

Infective endocarditis (VSD/PDA)

^{Requires prophylaxis antibiotics}

Hypertension (Coarctation)

Polycythemia (HCT > 65%)

^{Physiologic response to chronic hypoxemia - Increases risk for thromboembolism}

Coagulation defects

^{Deficiency in VT K clotting factors - Defective PLT aggregation}

Brain abscess development

Question 13

_{Problems Afflicting Patient with Congenital Heart Disease}

Congenital Heart Disease a/w Infective endocarditis (VSD/PDA) Requires Prophylaxis with which drugs?

Answer 13

Antibiotics

Question 14

_{Problems Afflicting Patient with Congenital Heart Disease}

Polycythemia (HCT > 65%) a/w Congenital Heart Disease is a physiologic response to:

Answer 14

Chronic hypoxemia

Question 15

_{Problems Afflicting Patient with Congenital Heart Disease}

Polycythemia (HCT > 65%) a/w Congenital Heart Disease increase risk for:

Answer 15

Thromboembolism

Question 16

_{Problems Afflicting Patient with Congenital Heart Disease}

Coagulation defects a/w Congenital Heart Disease are a consequence of:

Answer 16

Deficiency in Vit K clotting factors

Defective PLT aggregation

Question 17

_{Pathophysiology of Congenital Heart Disease}

T/F: Management of anesthesia for patients with CHD requires a thorough knowledge of the pathophysiology of each cardiac defect

Answer 17

True

However, this is confusing due to complexity of lesions

Utilization of a structured approach that emphasizes ratio of pulmonary blood flow & systemic blood flow based on resistance in these vascular beds is helpful

Question 18

_{Pathophysiology of Congenital Heart Disease}

Important pathophysiologic questions w/ CHD include:

Answer 18

Is there on obstruction?

Is there a shunt?

Question 19

_{Pathophysiology of Congenital Heart Disease}

What are the effects of R side obstruction?

Answer 19

Blood unable to go from RV to lungs

↓ pulmonary blood flow => hypoxemia/cyanosis

Blood does not get oxygenated

Question 20

_{Pathophysiology of Congenital Heart Disease}

What are effects of L side obstruction?

Answer 20

Blood unable to flow from LV to systemic circulation

Tissues organs do not get perfused

↓ systemic blood flow => hypoperfusion/acidosis/shock

Question 21

_{Pathophysiology of Congenital Heart Disease}

How can shunt be defined?

Answer 21

Mixing of pulmonary/systemic circulations

_{(or mixing of oxygenated and de-0xygenated blood)}

Question 22

_{Pathophysiology of Congenital Heart Disease}

What determines the direction of of shunt?

Answer 22

Ratio of pulmonary blood flow (Qp) / systemic blood flow (Qs)

Qp:Qs

Question 23

_{Pathophysiology of Congenital Heart Disease}

Qp:Qs < 1 means:

Answer 23

Pulmonary blood flow < Systemic blood

Instead of flowing to the lungs, blood is flowing to the left side

[R to L shunt]

Blood flowing directly to the left fails to be oxygenated

This leads to hypoxemia and cyanosis

Ineffective pulmonary blood & mixing systemic/pulmonary circulations => hypoxemia/cyanosis

Question 24

_{Pathophysiology of Congenital Heart Disease}

Qp:Qs > 1 means:

Answer 24

Pulmonary blood flow > Systemic blood

[L to R shunt]

Volume/pressure overload of R ventricle => CHF

Pulmonary overcirculation => Pulmonary HTN/ ↑ PVR

Question 25

_{Pathophysiology of Congenital Heart Disease} Qp:Qs = 1 means

Answer 25

No shunt Balanced flow Bi-directional shunt of equal magnitude

Question 26

_{Pathophysiology of Congenital Heart Disease} Shunt flow dependent on balance between PVR & SVR. ↑ PVR relative to SVR would lead to what shunt direction?

Answer 26

**R to L** shunt

Question 27

_{Pathophysiology of Congenital Heart Disease} Shunt flow dependent on balance between PVR & SVR. ↑ SVR relative to PVR would lead to a shunt in which direction?

Answer 27

**L to R** shunt

Question 28

_{Pathophysiology of Congenital Heart Disease} Factors that would increase PVR, cause a R-to-L shunt, and affect Qp:Qs Ratio include:

Answer 28

Hypoxia Hypercapnia Acidosis High PIP PEEP Hypothermia Polycythemia Decreased LV output

Question 29

_{Pathophysiology of Congenital Heart Disease} Factors that would decrease PVR, cause a L-to-R shunt, and affect Qp:Qs Ratio include:

Answer 29

High FiO2 Hypocapnia Alkalosis Improved LV output Anemia

Question 30

_{Classification of Congenital Heart Defects} Lesions causing left-to-right shunting (volume overload of the left ventricle or left atrium resulting in increased pulmonary blood flow) include:

Answer 30

Atrial Septal Defect Ventricular Septal Defect Patent ductus arteriosus Atrioventricular Septal Defect ^{(Common complete atrioventricular canal)}

Question 31

_{Classification of Congenital Heart Defects​} Lesions causing outflow obstruction (resulting in pressure overload on the left ventricle, and increased myocardial work) inlude:

Answer 31

**Aortic Stenosis** **Coarctation of the aorta\*** ^{(Narrowing of the aorta distal to the aortic valve)}

Question 32

_{Classification of Congenital Heart Defects​} Lesions causing right-to-left shunting (**cyanosis** resulting from obstruction/decreased pulmonary blood flow) include:

Answer 32

Tetralogy of Fallot Tricuspid atresia Pulmonary atresia

Question 33

_{Classification of Congenital Heart Defects​} Lesions causing right-to-left shunting (cyanosis due to mixing of the pulmonary and systemic circulations/increase pulmonary blood flow) include:

Answer 33

Hypoplastic left heart syndrome Truncus arteriosus

Question 34

_{Classification of Congenital Heart Defects​} Lesions causing separation of the pulmonary & systemic circulations

Answer 34

Transposition of the great vessels

Question 35

_{Classification of Congenital Heart Defects​} Acyanotic (L→R) shunt lesions include:

Answer 35

Ventricular Septal Defect Atrial Septal Defect Patent Ductus Arteriosus Atrioventricular Septal Defects ^{Common Complete Atrioventricular Canal} Aortic Stenosis Coarctation of the Aorta

Question 36

_{Classification of Congenital Heart Defects​} Cyanotic (R→L) shunt lesions include:

Answer 36

Tetralogy of Fallot Transposition of the Great Arteries Hypoplastic Left Heart Syndrome (HLHS) Tricuspid valve abnormalities (Ebstein’s anomaly) Truncus arteriosus Total anomalous pulmonary venous connection

Question 37

_{Acyanotic or Predominantly Left-to-Right Lesions} Pathophysiologic changes that accompany Left-to-Right shunt lesions include:

Answer 37

**Decreased systemic blood flow** ^{Low Cardiac output - Hypotension} **Increased pulmonary blood flow** ^{Pulm HTN - RVH}

Question 38

_{Acyanotic or Predominantly Left-to-Right Lesions} Hemodynamic goals for Left-to-Right shunt lesions include:

Answer 38

**Avoid increased SVR** **---** **Avoid decreased PVR** ^{How? => Decrease FiO2 - Hypoventilation (High FiO2 and Hypocapnia/hyperventiation will decrease PVR)} _Any of the above will worsen the shunt!!!_

Question 39

_{Acyanotic or Predominantly Left-to-Right Lesions} Pathophysiology of Left-to-Right Lesions:

Answer 39

Simple shunts with isolated abnormal communications between the L & R side of the heart Pressure L side heart \> Pressure R side heart =\> L-to-right shunt ^{Blood flow to R side heart & lungs increases} Shunt flow depends on balance between PVR & SVR ^{PVR < SVR => L-to-R shunting}

Question 40

_{Acyanotic or Predominantly Left-to-Right Lesions} Clinical manifestations:

Answer 40

Pulmonary vascular congestion Decreased lung compliance Increased work of breathing Chronic increases PBF ^{Irreversible ↑ PVR RVH → Cor Pulmonale}

Question 41

_{Acyanotic or Predominantly Left-to-Right Lesions} What's the most common acyanotic or predominantly Left-to-Right Lesion?

Answer 41

**Ventricular Septal Defect (VSD)** Most common (25%) Mostly "isolated" VSD = VSD w/o any other type of anomalies

Question 42

_{Acyanotic (L→R) - Ventricular Septal Defect (VSD)} Clinical symptoms related to size of shunt - what are Clinical symptoms of Small shunt?

Answer 42

No clinical symptoms

Question 43

_{Acyanotic (L→R) - Ventricular Septal Defect (VSD)} Clinical symptoms related to size of shunt - what are Clinical symptoms of Large shunt?

Answer 43

_Growth failure_ **CHF** Recurrent _pulmonary infections_ **Eisenmenger’s syndrome** (untreated)

Question 44

_{Acyanotic (L→R) - Ventricular Septal Defect (VSD)} Condition that arises when untreated Ventricular Septal Defect (VSD) leads to Pulmonary vascular disease =\> ↑ PVR, and Shunt reverses and flows R-to-L (cyanosis)

Answer 44

**Eisenmenger’s syndrome** Deadly during delivery or shortly after birth d/t severe cyanosis, b/c the body is unable to compensate for the acute change from L to R to R to L shunt flow

Question 45

_{Acyanotic (L→R) - Ventricular Septal Defect (VSD)} Shunt flow is determine by PVR & SVR. How does ↓ PVR & ↑ SVR affect an existing L-to-R shunt?

Answer 45

↑ L-to-R shunting _{(Makes it worse)}

Question 46

_{Acyanotic (L→R) - Ventricular Septal Defect (VSD)} Shunt flow is determine by PVR & SVR - How does ↑ PVR & ↓ SVR affect an existing L-to-R shunt?

Answer 46

↓ L-to-R shunting

Question 47

_{Acyanotic (L→R) - Ventricular Septal Defect (VSD)} T/F: Most small Acyanotic (L→R) defects close w/o intervention

Answer 47

**True** (40% by 3yrs and 75% by 10yrs)

Question 48

_{Acyanotic (L→R) - Ventricular Septal Defect (VSD)} How are Large Acyanotic (L→R) defects treated?

Answer 48

Require **surgical closure** before ↑ PVR irreversible

Question 49

_{Acyanotic (L→R) - Ventricular Septal Defect (VSD)} Anesthetic considerations similar to which other congenital heart defect?

Answer 49

ASD

Question 50

_{Acyanotic (L→R) - Ventricular Septal Defect (VSD)} Blood flow in VSD

Answer 50

See picture

Question 51

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)} Prevalence of ASD

Answer 51

Accounts for 7.5% of CHD

Question 52

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)} T/F: Most small Atrial Septal Defect (ASD) are asymptomatic, with spontaneous closure occurring in the 1st yr. of life

Answer 52

**True**

Question 53

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)​} Pathophysiology of large ASD

Answer 53

Acyanotic L to R shunt (pulmonary overflow)

Question 54

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)​} Symptoms of Atrial Septal Defect (ASD)​

Answer 54

DOE - SVT - CHF Pulmonary HTN Recurrent pulmonary infections

Question 55

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)​} Treatment of large Atrial Septal Defect (ASD)​

Answer 55

Requires **surgical repair** or **Placement of a device** via catheterization

Question 56

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)​} Blood flow in Atrial Septal Defect (ASD)​

Answer 56

See picture

Question 57

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)​} Anesthetic considerations for ASD and VSD will focus on avoiding which changes to which two hemodynamic variables?

Answer 57

Avoid **↑ SVR** ^{(worsen L-R shunting)} Avoid **↓ PVR** ^{(by avoiding high FiO2, and avoiding low ETCO2)}

Question 58

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)​} T/F: Anesthetic considerations for ASD and VSD include Strict avoidance of air emboli

Answer 58

True

Question 59

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)​} How does the L-to-R shunting affect the rate of **inhalation induction**? why?

Answer 59

**More rapid** with inhalation induction D/t _rapid decrease in the arterial to venous difference of agen_t *This is all theoretical - No real differences seen clinically*

Question 60

_{Acyanotic (L→R) - Atrial Septal Defect (ASD)​} How does the _L-to-R shunting_ affect the rate of **IV induction**? why?

Answer 60

**Slower rate** of IV inductions _D/t Diluted arterial blood concentration_ *This is all theoretical - No real differences seen clinically*

Question 61

_{Acyanotic (L→R)} Failure of ductus arteriosus to close after birth (review fetal circulation and transition at birth!) results in a condition called:

Answer 61

**Patent Ductus Arteriosus** (PDA)

Question 62

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} What's the prevalence of PDA? What age group is most affected?

Answer 62

**PDA** accounts for **7.5% CHD** Most common in the _premature infants_

Question 63

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} What are the causes of Patent Ductus Arteriosus (PDA)?

Answer 63

Hypoxemia Hypercarbia/acidosis Persistent pulmonary HTN in the newborn

Question 64

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} Which hemodynamic variables determine shunt flow in Patent Ductus Arteriosus (PDA)?

Answer 64

**SVR** & **PVR** _PDA is Nonrestrictive when SVR \> PVR_ Which results in L-to-R shunt _{(blood flow from aorta back into pulmonary artery}

Question 65

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} Blood flow in PDA

Answer 65

See image

Question 66

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} Clinical presentation of PDA:

Answer 66

**Pulmonary congestion** **CHF** ^{(widened pulse pressure, continuous systolic/diastolic murmur)}

Question 67

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} How long after birth should PDA be normally closed?

Answer 67

**2-3 days** after birth

Question 68

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} Medical Treatment of Patent Ductus Arteriosus (PDA)

Answer 68

**Indomethacin** (↓ PGE1 levels) Remember that it is the reduction in prostaglandins production after removal of the placenta that results in the closure of the ductus arteriosus Indomethacin reduces levels of prostaglandins (PGE1)

Question 69

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} When is Surgical ligation (NICU/Cath lab) of Patent Ductus Arteriosus (PDA) indicated?

Answer 69

Decreased **rena**l or **platelet** function ^{(contraindication to indomethacin use)} _Indomethacin unsuccessful_ Decreased **systemic oxygenation** due to shunting

Question 70

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} What surgical approch is used for ligation (NICU/Cath lab) of Patent Ductus Arteriosus (PDA)?

Answer 70

**Left thoracotomy** approach **Video-assisted ligation** (minimally traumatizing)

Question 71

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} What's a contraindication to indomethacin use?

Answer 71

Decreased **renal** or **platelet** function

Question 72

_{Acyanotic (L→R) - Patent Ductus Arteriosus (PDA)} Anesthetic considerations for PDA are similar to Anesthetic considerations for which other Acyanotic (L→R) lesions?

Answer 72

**ASD/VSD** Avoid increasing SVR =\> this will worsen the shunt Avoid decreasing PVR =\> by avoiding high FiO2 and hyperventilation

Question 73

_{Acyanotic (L→R)} Which anatomical defects are present in Atrioventricular Septal Defects?

Answer 73

**ASD** **VSD** **Single atrioventricular valve** ^{Lack of separation of the mitral and tricuspid valves}

Question 74

_{Acyanotic (L→R) - Atrioventricular Septal Defects} Atrioventricular Septal Defects are common in children with which genetic condition?

Answer 74

**Trisomy 21** | (Down syndrome)

Question 75

_{Acyanotic (L→R) - Atrioventricular Septal Defects} What are the characteristics of Shunt flow w/ AVSD in the initial neonatal period? why is that and what does that results in?

Answer 75

**Bidirectional** D/t **↑ PVR** Results in _mild hypoxemia_

Question 76

_{Acyanotic (L→R) - Atrioventricular Septal Defects} How is Shunt flow in AVSD with ↓ PVR

Answer 76

Predominantly **L to R**

Question 77

_{Acyanotic (L→R) - Atrioventricular Septal Defects} What are the Symptoms of AVSD?

Answer 77

CHF Tachypnea/dyspnea Poor feeding Pulmonary HTN ^{(with pulmonary vascular disease developing overtime)}

Question 78

_{Acyanotic (L→R) - Atrioventricular Septal Defects} What's the Treatment for AVSD?

Answer 78

**Surgical repair** required within the _1st year of life_

Question 79

_{Obstructing Lesions} What's the prevalence of Congenital _Aortic Stenosis_?

Answer 79

Accounts for **5% of all CHD**

Question 80

_{Obstructing Lesions - Congenital Aortic Stenosis} Anatomic and physiologic changes a/w **congenital Aortic Stenosis** include:

Answer 80

**Unicuspid** or **bicuspid** stenotic valve **↑ LVEDP** & ↑ LAP =\> _Pulmonary edema_ **L to R shunt** at _atrial level_ **Concentric LVH** with_↑ Myocardial O2 requirements_

Question 81

_{Obstructing Lesions - Congenital Aortic Stenosis} T/F: Symptoms of Congenital Aortic Stenosis are related to severity of stenosis and ventricular function

Answer 81

True

Question 82

_{Obstructing Lesions - Congenital Aortic Stenosis} Systemic blood flow in neonate with critical Congenital Aortic stenosis is dependent on:

Answer 82

Maintaining a **Patent Ductus Arteriosus** Ductal-dependent systemic blood flow **(R-L shunting)** _Closure of PDA_ after birth =\> **cardiogenic shock**

Question 83

_{Obstructing Lesions - Congenital Aortic Stenosis} What's the treatment for critical Congenital Aortic stenosis in Neonate?

Answer 83

Prostaglandin E1 to **maintain open ductus arteriosus** until definitive surgery can be performed

Question 84

_{Obstructing Lesions - Congenital Aortic Stenosis} Congenital Aortic Stenosis is most commonly diagnosed in older children. What s/s is it a/w?

Answer 84

**Angina pectoris** w/o CAD (LVH) _CHF_ **Syncope**

Question 85

_{Obstructing Lesions - Congenital Aortic Stenosis} In Critical AS, the aortic valve opens, but cannot supply enough blood to the body. Some part of the blood supply to the body must be supplied by

Answer 85

A **Patent Ductus Arteriosus**

Question 86

_{Obstructing Lesions - Congenital Aortic Stenosis} Surgical intervention for Congenital Aortic Stenosis include

Answer 86

Valvuloplasty/Valvotomy Valve replacement

Question 87

_{Obstructing Lesions - Congenital Aortic Stenosis} Why do Surgical intervention for Congenital Aortic Stenosis include require prophylactic antibiotics?

Answer 87

These pts are _predisposed_ to **infective endocarditis**

Question 88

_{Obstructing Lesions - Congenital Aortic Stenosis} Anesthetic management of peds with Congenital Aortic Stenosis is the same as for the adult patient with aortic stenosis. What does it entail?

Answer 88

Avoid **sudden↓ SVR** _Maintain_ **NSR** Avoid **bradycardia** (↓ C.O.) Avoid **tachycardia** (impairs ventricular filling) Optimize volume to _maintain_ **venous return** & **LV** filling pressures Predisposed to infective endocarditis =\> **prophylactic antibiotics** Avoid **hyperoxygenation** ^{↑PBF thus reducing systematic blood flow Accept SaO2 > 75% Reduce FiO2 SaO2 > 85%} _Maintain_ **Controlled hypoventilation** (↑ PVR) ^{If there is excessive PBF (SaO2 > 85%) & reduced SBF (↓ MAP)}

Question 89

_{Obstructing Lesions - Congenital Aortic Stenosis} In the Anesthetic management of peds with Congenital Aortic Stenosis, why must **hyperoxygenation** be _avoided_?

Answer 89

Decreases PVR =\> ↑ pulm blood flow (PBF) =\> reduced systematic blood flow Accept SaO2 \> 75% Reduce FiO2 SaO2 \> 85%

Question 90

_{Obstructing Lesions - Congenital Aortic Stenosis} In the Anesthetic management of peds with Congenital Aortic Stenosis, which intervention is appropriate if there is excessive PBF (SaO2 \> 85%) & reduced SBF (↓ MAP)?

Answer 90

**Controlled hypoventilation** (to ↑ PVR)