Translations:Herz/125/en
In the case of a malfunction, audible flow noises are caused by the formation of whirls in the blood. Cardiac auscultation is an old but important method for recognizing these sounds. It is used both for the initial detection and the follow-up of functional disorders. The basis is that two sounds can be heard in a healthy adult heart. The first heart sound (S1) is at the beginning of systole. The tone is produced by the blood column hitting the leaflet valves and not, as is often assumed, by the closure of the valves. The second heart sound (S2) is produced by the closure of the leaflet valves at the end of systole. It is much brighter than the first heart sound. The two sounds are clearly audible at different locations. The first heart sound is clearly heard above the apex of the heart, whereas the second heart sound is clearly heard above the base of the heart. At Erb's point, which is located on the left parasternal side in the third intercostal space, all heart valves can be detected equally well. Specific points on the chest are recommended for auscultation of individual heart valves, as the sounds are projected to these locations and can thus be heard loudest:
- Aortic valve: 2/3rd intercostal space right parasternal.
- Pulmonary valve: 2nd intercostal space left parasternal
- Tricuspid valve: 4th intercostal space right parasternal
- Bicuspid valve: 5th intercostal space left medioclavicular
