Ventricular Septal Defect

Question 1

True or false: Atrial Septal Defect is the most common congenital heart disease?

Answer 1

False
Ventricular septal defect is

Question 2

The majority of VSDs are ___-to_____ shunts

Answer 2

left-to-right

Question 3

What does restrictive VSD mean and what are the symptoms?

Answer 3

Restrictive VSD means it is very small and the flow of blood through is minimal.
Patients tend to be asymptomatic

Question 4

What are risk factors for VSDs?

Answer 4

Maternal diabetes mellitus
Maternal rubella infection
Foetal alcohol syndrome
Uncontrolled maternal phenylketonuria (PKU)
Family history of VSD
Down’s syndrome
Turner’s syndrome
Trisomy 18 (Edward’s)
Trisomy 13 (Patau’s)

Question 5

How are small VSDs normally identified?

Answer 5

A systolic murmur is detected during a routine exam

Question 6

How may a patient with a VSD appear?

Answer 6

Cyanotic
Increased work of breathing
Fast rate of breathing
Sweaty (increased sympathetic activity to compensate for decreased cardiac output)
Undernourished (fatigue during feeding)
Clubbing

Question 7

What does clubbing show and why?

Answer 7

Clubbing can be a sign of long standing desaturation, too mild to cause blue complexion.
It is thought that venous blood bypasses pulmonary capillaries so the lungs don’t clear megakaryocytes but these instead lodge in the nail beds. They then release platelet derived growth factor which stimulates connective tissue hypertrophy.

Question 8

What can be palpated in a patient with VSD?

Answer 8

Increased pulse rate (raised in congestive failure)
Hyperactive precordium (area above heart is moving too much caused by volume overload)
Thrills

Question 9

What would be heard on auscultation of a VSD?

Answer 9

Pan-systolic murmur
Best heard at lower left sternal border in tricuspid area
Small VSD results in louder murmur

At apex may hear a diastolic murmur like mitral stenosis due to (more volume of blood entering pulmonary system so) more blood filling the left atria and ventricle

Question 10

How to quickly differentiate ASDs from VSDs?

Answer 10

Think Very Strong Down in VSD = harsh pansystolic murmur at lower left sternal border with thrill. Loudest in small defects.

Think vowels and “always split defect” in ASD = Ejection systolic murmur at pulmonary area with wide fixed splitting of S2.

Question 11

How is a VSD differentiated from mitral regurgitation?

Answer 11

Both have a pan-systolic murmur heard in the same region.
Echocardiogram needed to differentiate.

Question 12

How to differentiate between a VSD and tricuspid regurgitation?

Answer 12

Characteristic of tricuspid regurgitation is an increase in the murmur intensity with inspiration (Carvalho’s sign)

Question 13

What may an ECG show in a patient with a VSD?

Answer 13

Signs of left ventricular hypertrophy or bilateral ventricular hypertrophy

Question 14

What blood tests should be done in suspected VSD?

Answer 14

Septic screen if child collapses or deteriorates
Kidney function before treating with ACE-i or diuretics
Microarray if genetic syndromes suspected

Question 15

What imaging would be done for suspected VSD?

Answer 15

Echocardiography is gold standard

Chest X-ray - large VSD may show cardiomegaly, pulmonary oedema and pleural effusion

Cardiac CT angiography
MRI

Question 16

What investigation can determine relative pressures and pulmonary vascular resistance to see how significant shunt is in VSD?

Answer 16

Cardiac catheterisation

Question 17

What other medical advice is given to patients with a VSD?

Answer 17

Maintain good oral hygiene to decrease risk of infective endocarditis

Question 18

What is the medical management for children with VSDs to relieve symptoms?

Answer 18

Increased caloric density of feedings to ensure adequate weight gain (possible NG tube)

Diuretics to relieve pulmonary congestion (often spironolactone to minimise potassium loss)

ACE-inhibitors reduce arterial pressures so more blood flows through aortic valve than shunt (note ACE-i can increase serum potassium so stop spironolactone)

Some places use digoxin for congestive heart failure to increase heart muscle strength and remove excess water from body.

Question 19

What definitive treatment is there for VSD?

Answer 19

For moderate-large VSD, surgery to close defect.
Open heart surgery with cardiopulmonary bypass via median sternotomy.
Or less commonly, catheter procedure via groin under GA.

Question 20

What are complications of VSD?

Answer 20

Infective endocarditis - avoid piercings, tattoos and maintain good dental hygiene
Congestive heart failure
Growth failure
Aortic valve regurgitation
Pulmonary vascular disease and Eisenmenger’s syndrome
Recurrent chest infections
Arrhythmias
Sudden death

Question 21

What are some major adverse events following surgical repair of VSD?

Answer 21

Permanent heart block requiring pace-maker
Other arrhythmias
Wound infection

Question 22

__% of small VSDs close spontaneously by the age of __ years

Answer 22

75%
10 y/o