Heart sounds/murmurs Flashcards
What is a heart murmur?
Sound produced when blood flowing through the heart is turbulent.
Causes of heart murmurs
- Abnormal narrowing (e.g. stenosis)
- Blood flowing the wrong direction (regurgitation)
- Abnormal connection between parts of the heart (mixing of blood or too much blood in a heart chamber)
- Blood flowing faster through the heart
Transmitted heart murmurs
Structural defects result in turbulence that continues to be heard in the direction of blood flow
Examples of transmitted murmurs
Aortic stenosis radiates to carotid arteries
Mitral regurgitation radiates to the axilla
Cause of systolic murmur
- Aortic/pulmonary stenosis
- Mitral and tricuspid regurgitation
- Mitral valve prolapse - systolic murmur with opening click
Cause of early diastolic murmur
Aortic and pulmonary regurgitation
Cause of mid/late-diastolic murmur
Mitral and tricuspid stenosis
Ejection systolic (crescendo-decrescendo) murmur
Aortic and pulmonary stenosis
Pansystolic murmur
Mitral and tricuspid regurgitation
Other causes of ejection systolic murmurs
Aortic sclerosis and Hypertrophic obstructive cardiomyopathy (HOCM).
Atrial septal defects and pulmonary stenosis
Characteristics of aortic sclerosis and HOCM
Both loudest in aortic valve area during expiration.
Aortic stenosis radiates to carotids, HOCM and aortic sclerosis do not
Characteristics of atrial septal defects and pulmonary stenosis
Both loudest in pulmonary region
Atrial septal defects cause wide and fixed splitting of S2 whereas pulmonary stenosis does not
Aortic area loudest heard?
In 2nd intercostal space right sternal edge
Pulmonary area loudest heard?
2nd intercostal space left sternal edge
Tricuspid area loudest heard?
4th intercostal space left sternal edge