Ventricular Septal Defect

Question 1

What are the clinical examinations/findings of VSD?

Answer 1

Pansystolic murmur and thrill over left lower sternal edge
Mid diastolic murmur at apex with right ventricular heave

A. Inspection
- Syndromes
- Look for signs of IE
- Clubbing (rare, Eisenmenger)
- Cyanosis (Eisenmenger)

B. Apex beat - displaced, thrusting

C. Heart sound and murmur
- PSM over LLSE, radiating towards right side of sternum, louder on expiration
- Palpable systolic thrill
- Widely splitted S2 -> single loud P2 (Eisenmenger)
- Concomittant EDM from AR, functional MS

D. Complications
- PHT, Eisenmenger - PSM over tricuspid, cyanosis and clubbing
- Heart failure

Question 2

What are the causes of a ventricular septal defect?

Answer 2

Maternal DM/alcoholism, syndromic, TOF, post-MI, traumatic

Congenital
- Maternal diabetes
- Maternal alcohol syndrome
- Maternal phenylketonuria
- Syndromes: Down, Edward, Patau, Di George

Acquired
- Traumatic
- Post-op (alcohol septal ablation, RV pacing with septal puncture)
- Post-MI

Question 3

What medical conditions are associated with VSD?

Answer 3

1. Tetralogy of Fallot
2. Truncus arteriosus
3. AV canal defect
4. Double outlet RV (DORV)

Question 4

What are the complications of ventricular septal defects?

Answer 4

1. Infective endocarditis
2. Pulmonary hypertension
3. Left ventricular dysfunction
4. Aortic regurgitation
5. Arrhythmia
6. Eisenmeinger’s syndrome
7. Paradoxical embolism

Question 5

How would you investigate a patient with a ventricular septal defect?

Answer 5

ECG
- Normal in small defect
- LVH, RVH, LAH (p mitrale)
- Pulmonary hypertension: p pulmonale, RAD

CXR
- Normal in small defects
- Cardiomegaly, LAH, LVH
- Signs of pulmonary hypertension
- Signs of CCF

TTE
- Location, size and direction of shunt (Colour Doppler)
- Ventricular function
- PASP

Cardiac catheterisation

Question 6

How would you manage a patient with a ventricular septal defect?

Answer 6

1. Reassurance if small and no pulmonary hypertension
2. Medical management
   - Endocarditis prophylaxis
   - Diuretics
   - Treatment of left ventricular dysfunction
   - Treatment of pulmonary hypertension
3. Surgical closure: open surgery vs percutaneous transcatheter
   - Evidence of PHT, CCF
   - Right to left flow ratio > 2
   - Recurrent IE
   - AR
   - Acquired cause: septal rupture in MI

Contraindications to closure: Eisenmenger’s syndrome

Question 7

Are there any contraindications to closure of a ventricular septal defect?

Answer 7

Irreversible severe pulmonary hypertension and Eisenmeinger’s syndrome

Question 8

What are the types of VSD?

Answer 8

1. Perimembranous (infracristal): lie in LV outflow tract just below AV (commonest)
2. Supracristal: lie beneath PV and communicate with RV outflow tract, associated with AR
3. Muscular: in muscle septum
4. Posterior: lie posterior to septal leaflet of TV
   - Maladie de Roger (small VSD, haemodynamically insignificant, loud murmur)
   - Swiss cheese
   - Gerbode defect (LV opens into RA)

Question 9

How do you differentiate TOF from isolated VSD?

Answer 9

1. Pulmonary thrill, PS murmur
2. Clubbed, central cyanosis (in TOF, rarely in VSD with Eisenmenger)

Question 10

How do you differentiate HOCM from VSD?

Answer 10

1. ESM instead of PSM
2. Apex not displaced, with double apical impulse
3. Jerky impulse

Question 11

Does the loudness of murmur correlate with severity of VSD?

Answer 11

No - small VSD causes louder murmur, converse is true
(Maladie de Roger - small VSD haemodynamically insignificant causes loud murmur)