Left to Right Shunts

Question 1

What is ASD?

Answer 1

Atrial Septal Defect

Secundum ASD (80% of ASDs) – defect in atrial septum (foramen ovale does not close)

o Partial AVSD (or ‘primum ASD’) – defect of AV septu

Question 2

Signs and symptoms of ASD?

Answer 2

Asymptomatic

o Recurrent chest infections / wheeze

o Arrhythmias (from 40yo+)

o Murmur:

Ejection-Systolic Murmur at ULSE

Fixed wide splitting of S2

Question 3

Investigations of ASD?

Answer 3

CXR

ECG

Echoardiography

Question 4

Management of ASD?

Answer 4

Secundum ASD -> cardiac catheterisation + insertion of occlusive device (percutaneous/endovascular closure)

Partial AVSD -> surgical correction

Question 5

What is VSD?

Answer 5

Ventricular Septal Defect

this is based on size <3mm or >3mm

Question 6

Symptoms of a small <3mm VSD?

Answer 6

Asymptomatic

Murmur = loud PAN-SYSTOLIC MURMUR

Question 7

Investigations and Management of <3mm VSD?

Answer 7

Echocardiography

Self limiting - these close by themselves

Question 8

Signs and symptoms of large VSD?

Answer 8

Heart Failure , SOB, recurrent chest infections, hepatomegaly

Question 9

Investigations and management of a large VSD?

Answer 9

CXR
ECG
Echocardiography

Diuretics + captopril
additional calorie input
surgery is performed at 3-6 months to prevent permanent lung damage.

Question 10

What is Patent Ductus Arteriosus?

Answer 10

Connects pulmonary artery to descending aorta (should close by 1 month postpartum)

Question 11

Signs and symptoms of Patent Ductus Arterious?

Answer 11

Murmur = continuous ‘machine-like’ / Gibson’s murmur at ULSE

Left sub-clavicular thrill

Heaving apex beat

Wide pulse pressure

Large volume, bounding, collapsing pulses

Respiratory symptoms (increased work) à apnoea, bradycardia, high O2 need

Question 12

Investigation and Management of Patent Ductus Arteriosus?

Answer 12

Medical: indomethacin (NSAID) à will promote duct closure

o Surgical: coil/device closure at cardiac catheter at 1yo, or Ligation

Question 13

What is Cyanotic Heart Disease?

Answer 13

Present with cyanosis - hyperoxia nitrogen washout test

Question 14

What is Tricuspid Atresia?

Answer 14

The most common form of complex cyanotic

heart disease (there are many others)

· Only left ventricle effective (right too small)

Question 15

What are some signs and symptoms of Tricuspid Atresia?

Answer 15

Cyanosis and SoB

§ Presents very early (10mins)

§ Similar to ToF presentation but ToF presents at 1-6m of age

o ESM at left sternal edge

o Hypoplastic left heart

Question 16

Management of Tricuspid Atresia?

Answer 16

1 - secure supply of blood to the lungs

2 - Glenn operation -> SVC to the pulmonary artery

3 - Fontan operation -> IVC to the pulmonary artery

Question 17

What is Transposition of the Great Arteries?

Answer 17

Two main vessels OUT of the heart are switched (Pulmonary Artery and Aorta)

• Aorta is connected to the right atrium, PA to the left atrium.
• Oxygenated blood goes to the lungs and deoxygenated blood is sent to the body.

Question 18

What are some signs and symptoms of TGA?

Answer 18

Cyanosis within a few hours

Loud S2 (but, no murmur)

Question 19

Investigations for TGA?

Answer 19

CXR - narrow upper mediastinum
increased pulmonary markings

Echocardiography

Question 20

Management of TGA?

Answer 20

immediate prostaglandin infusion (vasodilatory - mantains patency of the ductus arteriosus)

balloon atrial septoplasty - tears atrial septum down to enable mixing

Question 21

What is an atrioventricular septal defect? And what are the signs

Answer 21

Common in downs syndrome

Cyanosis at weeks 2-3 of life (no murmur) à found on routine echocardiography of Down’s

Question 22

What is Tetraology of Fallot?

Name some characteristics?

Answer 22

Most common cause of cyanotic heart disease

VSD

Overriding aorta (compresses pulmonary outflow -> stenosis -> RVH)

Question 23

What are some symptoms of TOF?

Answer 23

Clubbing

o Murmur = loud ESM at left lower sternal border

o Tet spells = crying à inc. pul. resistance à R-L shunt à cyanosis

Question 24

Investigations for TOF?

Answer 24

CXR (small heart, boot-shaped due to RVH)

Echocardiography

Question 25

Management of TOF?

Answer 25

1 - Prostaglandin to reverse severe cyanosis

• morphine
• propanolol - peripheral vasoconstriction
• IV fluids
• muscle paralysis and artificial ventilation

2 - surgery - post 6 months

Question 26

What is Eisenmenger Syndrome?

Answer 26

irreversibly raised pulmonary vascular resistance from chronically raised pulmonary arterial pressure and flow

At 10-15y, shunt reverses and teenager become blue + cyanotic with Eisenmenger syndrome à death by right-sided heart failure (40-50yo)

§ Cyanosis typically affects lower extremities in PDA-Eisenmenger

Question 27

Management of Eisenmenger Syndrome?

Answer 27

Early intervention for pulmonary blood flow

Heart transplantation not easy but can be done