Cardiology - Valve Stenosis

Question 1

What is coarctation of the aorta?

Answer 1

Narrowing of the aortic arch around the ductus arteriosus

Question 2

What genetic condition is coarctation of the aorta associated with?

Answer 2

Turners syndrome

Question 3

What happens to blood pressure in aortic coarctation?

Answer 3

Distal to the narrowing = pressure is decreased

Proximal to narrowing = pressure is increased

Question 4

How does coarctation of the aorta present?

Answer 4

• Weak femoral pulses
• Systolic murmur below left clavicle and below left scapula
• Tachypnoea
• Poor feeding
• Grey and floppy baby

After a period of time due to development
- LV heave, due to hypertrophy
- Underdeveloped left arm where there is reduced blood flow to left subclavian
- Underdevelopment of legs

Question 5

What can be done to identify coarctation of the aorta?

Answer 5

Four limb blood pressure

High blood pressure in limbs before narrowing
Low in limbs after narrowing

Question 6

How is coarctation of the aorta managed?

Answer 6

Mild cases are symptom free until adulthood

Severe cases needed emergency surgery after birth

Critical cases
- Risk of heart failure and death
- Prostaglandin E used to keep ductus arteriosus open while waiting for surgery
- Surgery then performed to correct coarctation and ligate ductus arteriosus

Question 7

What are the aortic valve leaflets called?

Answer 7

Aortic sinuses of Valsalva

Patients with congenital aortic valve stenosis can have 1,2,3 or 4 leaflets instead of the usual 3

Question 8

How does aortic valve stenosis present?

Answer 8

Mild
Asymptomatic
Discovered as incidental murmur during routine examination

Significant
Symptoms of fatigue
SOB
Dizziness and fainting

Symptoms are worse on exertion as outflow from LV cannot keep up with demand

Question 9

How does severe aortic stenosis present months after birth?

Answer 9

Heart failure

Question 10

What are the signs of aortic stenosis?

Answer 10

• Ejection systolic murmur heard best at the aortic area, crescendo-decrescendo character that radiates to carotids
• Ejection click just before murmur
• Palpable thrill during systole
• Slow rising pulse
• Narrow pulse pressure

Question 11

What investigations are used for aortic stenosis?

Answer 11

Gold standard
Echocardiogram

ECGs
Exercise testing
(to monitor progression of the condition)

Question 11

How is aortic stenosis treated?

Answer 11

Percutaneous balloon aortic valvopalsty
Surgical aortic valvotomy
Valve replacement

Question 12

What are the complications of aortic stenosis?

Answer 12

Left ventricular outflow tract obstruction
Heart failure
Ventricular arrhythmia
Bacterial endocarditis
Sudden death, on exertion

Question 13

What happens in congenital pulmonary valve stenosis?

Answer 13

Valve leaflets develop abnormally, becoming thickened or fused

Causes narrow pulmonary valve

Question 14

What is congenital pulmonary valve stenosis associated with?

Answer 14

Tetralogy of Fallot
William syndrome
Noonan syndrome
Congenital rubella syndrome

Question 15

How does pulmonary stenosis present?

Answer 15

Often completely asymptomatic, discovered incidentally as a murmur on routine baby checks

More signicant
- Fatigue on exertion
- SOB
- Dizziness and fainting

Question 16

What are the signs of pulmonary stenosis?

Answer 16

Ejection systolic murmur heard best at the pulmonary area
Palpable thrill in the pulmonary area
RV heave due to RVht
Raised JVP with giant a waves

Question 17

What investigations are used for pulmonary valve stenosis?

Answer 17

Gold standard
Echocardiogram

Question 18

How are patients with pulmonary valve stenosis managed?

Answer 18

Mild- Watchful waiting

Symptomatic or more significantly stenosed
- Balloon valvuloplasty via venous catheter
- Open-heart surgery (second line)

Question 19

What is Tetralogy of Fallot?

Answer 19

POSH

Pulmonary stenosis
Overriding aorta
Septal defect (ventricular)
Hypertrophy of RV

Question 20

What is an overriding aorta?

Answer 20

Aortic valve is further to the right than normal

Above the VSD

So when the RV contracts and blood sent upwards, aorta is in the direction of travel of the blood

More deoxygenated blood enters the aorta from the right side of the heart

Question 21

What causes right to left shunting in TOF?

Answer 21

Stenotic pulmonary valve increases resistance

This increases the pressure in the RV, encoruage blood to flow from right to left

Increased strain leads to RVht

Pressure in the RV > LV, blood bypasses lungs causes cyanosis

Question 22

What is the key factor in right to left shunting in TOF?

Answer 22

Severity of pulmonary stenosis

Question 23

What are the risk factors of TOF?

Answer 23

Rubella
Increased age of mother (over 40)
Alcohol during pregnancy
Diabetic mother

Question 24

What investigations are used for TOF?

Answer 24

**Echocardiogram**, investigation of choice for diagnosis **Doppler flow studies**, assessing severity of the abnormality and shunt **CXR** Shows characteristic **boot shaped** heart due to RVht

Question 25

How does TOF present?

Answer 25

- Most picked up before birth during **antenatal scans** - Ejection systolic murmur caused by pulmonary stenosis heard on new-born baby check - If severe will present with heart failure before 1 - In milder cases can present as older children when they develop heart failure symptoms

Question 26

What are the signs of TOF?

Answer 26

**Tet spells** **Cyanosis** Clubbing Ejection systolic murmur Poor feeding Poor weight gain

Question 27

What are tet spells?

Answer 27

Intermittent symptomatic periods where right to left shunt is worsened precipitating a cyanotic episode `

Question 28

What is the physiology of a tet spell?

Answer 28

Pulmonary vascular resistance increases or systemic vascular resistance decreases e.g. if lots of exertion, carbon dioxide acts as a vasodilator, decreasing systemic vascular resistance Blood therefore will be pumped from RV to aorta bypassing lungs

Question 29

What are the causes of a tet spell?

Answer 29

Waking Physical exertion Crying **Severe spells** Can cause reduced consciousness Seizures Death

Question 30

How are tet spells treated?

Answer 30

**Older** children may squat **Younger** children positioned with knees to their chest Increases the systemic vascular resistance **Medical treatment** - Supplementary oxygen - Beta blockers, relaxes RV - IV fluids to increase pre-load to increase blood flow to pulmonary vessels - Morphine, decreases respiratory drive - Sodium bicarbonate- metabolic acidosis - **Phenylephrine infusion**- increase systemic vascular resistance

Question 31

What can be given in neonates to allow blood flow to pulmonary arteries in TOF?

Answer 31

Prostaglandin infusion to maintain ductus arteriosus Bloods flows back from aorta to pulmonary vessels

Question 32

What is the definitive management of TOF?

Answer 32

Total surgical repair by open heart surgery 5% mortality

Question 33

What is the prognosis of TOF?

Answer 33

Poor without treatment With corrective surgery, 90% live to adulthood

Question 34

What is Ebstein's anomaly?

Answer 34

Congenital heart condition where tricuspid valve is set lower in right side of the heart Causes a bigger RA and smaller RV and an atrial septal defect

Question 35

What does Ebstein's anomaly lead to?

Answer 35

Poor flow from RA to RV, therefore poor flow to pulmonary vessels Associated with a right to left shunt across ASD Leads to cyanosis

Question 36

What is Ebstein's anomaly associated with?

Answer 36

Wolf-Parkinson-White syndrome

Question 37

How does Ebstein's anomaly present?

Answer 37

Evidence of heart failure Gallop rhythm on auscultation Cyanosis SOB and tachypnoea Poor feeding Collapse or cardiac arrest

Question 38

When do symptoms of Ebstein's anomaly present?

Answer 38

Few days after birth when ductus arteriosus closes When there is right to left shunt via ductus arteriosus allows blood to get oxygenated

Question 39

How is Ebstein's anomaly diagnosed?

Answer 39

Echocardiogram And used for assessing severity

Question 40

How is Ebstein's anomaly managed?

Answer 40

**Medical management** - Treat arrhythmias - Treat heart failure - Prophylactic antibiotics for potential endocarditis **Surgical** - Fix the underlying defect

Question 41

What is transposition of the great arteries?

Answer 41

Condition where attachments of aorta and pulmonary trunk are swapped RV pumps blood into aorta LV pumps blood into pulmonary vessels Two separate circulations that don't mix

Question 42

What is transposition of the great arteries associated with?

Answer 42

Ventricular septal defect Coarctation of the aorta Pulmonary stenosis

Question 43

What happens during pregnancy with transposition of the great arteries?

Answer 43

Gas and nutrient exchange occurs at placenta After birth there is immediate threat to life Baby will be cyanosed

Question 44

What does immediate survival depend on in transposition of the great arteries?

Answer 44

Shunt between systemic circulation and pulmonary circulation Allows some oxygenation to occur PDA ASD VSD

Question 45

How is TOGA diagnosed?

Answer 45

Diagnosed during pregnancy with **antenatal ultrasounds** Should be arranged in a hospital capable of managing the condition

Question 46

How does TOGA present?

Answer 46

Cyanosis at or within a few days of birth Respiratory distress Tachycardia Poor feeding Poor weight gain Sweating

Question 47

How is TOGA managed?

Answer 47

VSD allows some mixing of blood to provide time for definitive management **Prostaglandins** - Used to maintain ductus arteriosus **Balloon septostomy** - Catheter into foramen ovale via umbilicus - Inflating balloon to create a large ASD **Open heart surgery**- Definitive management - Cardiopulmonary bypass machine used to perform an **arterial switch** procedure within a few days of birth, can fix any VSDs or ASDs at same time