Heart Sounds Tutorial

Table of Contents

1. Introduction
2. The Basics
3. Murmurs
   1. Benign murmurs
   2. Murmurs II
   3. Aortic Stenosis
   4. Mitral Regurgitation
   5. Aortic Regurgitation
   6. Mitral Stenosis
   7. Tricuspid Valve
   8. Pulmonic Valve
   9. Ventricular Septal Defect
   10. Patent Ductus Arteriosus
   11. Atrial Septal Defect
   12. Coarctation of the Aorta
   13. Mitral Valve Prolapse
4. Extracardiac Sounds
5. MCQ
6. Acknowledgements and References

Ventricular Septal Defect

This is the single most common congenital cardiac abnormality

Anatomy

The Ventricular Septum (bit between the two ventricles) is made up of two parts the Membranous and Muscular parts respectively the former is the most common site for a Ventricular Septal Defect (VSD) but, if a VSD occurs in the muscular part it is likely to be more complex.

The neonate

In utero a large VSD can cause failure of the LEFT ventricle, this is because the RV has very high pressures in utero which will damage the left ventricle, signs apart from the murmurs discussed later will include Failure to Thrive, Tachypnoea and Hepatomegaly.

The Adult

1

In the neonate we said that there was a right-to-left shunt, what is likely to happen in you or I if we had a moderately sized hole inbetween our ventricles a) Left Ventricular Failure b) Right Ventricular Failure c) Pulmonary Hypertension d) Systemic Hypertension e) Dyspnoea a) Yesa) No, you would not get thisb) Yesb) You would get right ventricular failure as the higher pressured blood from the LV would enter the RV causing distension and damagec) Yesc) No, you would get blood flowing from the LEFT ventricle into the RIGHT as the right is at lower pressured) Yesd) Noe) Yes, shortness of breath due to the pulmonary hypertensione) No, this is shortness of breath which would occur secondary to the pulmonary hypertension

Murmur

2	Is the murmur going to be Systolic a) True b) False Correct, it will occur when there is the greatest pressure gradient between the ventricles, and also if the ventricles are stretched it can open up a holeNo, try ticking TRUE for an explanation!Your answer has been saved.

A small VSD will produce a much larger murmur than a large VSD which can be quite quiet, due to the larger pressure gradient.

A small VSD will produce a pan-systolic murmur, which will radiate to the axilla and the apex

A large VSD will produce a pan-systolic murmur, which may not radiate if it is quiet but will probably also show signs of ventricular hypertrophy.

The following is an example of a pan-systolic murmur caused by a VSD

VSD

Note

At the age of 3 over 30% of VSD in children will have spontaneously closed and many more by the age of 10 afterwhich if the VSD still persists surgery to close it is usually performed.