Normal Heart SoundsNormally, only heart sounds S1 and S2 can be heard. Murmurs occur if there is turbulent blood flow, which usually occurs as a result of valve pathology.
|Mechanism of murmur||Turbulent blood flow caused by travelling through tight space||Blood travels back into the heart against normal blood flow|
|Mechanism of murmur||Blood travels back into the heart against normal blood flow||Turbulent blood flow caused by travelling through tight space|
Continuous/Machinery murmursContinuous murmurs occur when there is a pressure gradient present throughout the cardiac cycle. Thus, the murmur is heard during both systole and diastole.
CausesPatent ductus arteriosus
Flow murmursFlow murmurs are innocent, benign murmurs that are especially common in young patients. They are characterised by the following:
- Systolic only
- Sound soft
- Varies with posture
- No thrill present