QS Study

Area of Heart Sound

The vibratory motion of heart during the different phases of the cardiac cycle produces a special audible sound known as heart sound. Many pathologic cardiac conditions can be diagnosed by auscultation of the heart sounds.

There are four area of the heart sound. These are –

(a) Mitral area: On the apex beat, in the left 5th intercostal space, 9 cm from the midsternal line. It is the region of the chest over the apex of the heart, where the sounds, normal or pathologic, produced at the mitral valves is generally heard most distinctly. This is one of the heart’s four valves that help avert blood from flowing backward as it moves through the heart.

Fig: Area of Heart Sound

(b) Tricuspid area: Over the left border of the sternum in the left 4th intercostal space. It is the region of the chest wall over the lower part of the body of the sternum, where the sounds produced at the tricuspid valve are heard most distinctly.

(c) Aortic area: Over right 2nd intercostal space close to the right border of the sternum. It is the region of the chest wall over the second right costal cartilage, where sounds produced at the aortic orifice are often best heard.

(d) Pulmonary area: Left 2nd intercostal at the margin of the sternum. It is the region of the chest at the second left intercostal space, where sounds produced at the pulmonary valve of the right ventricle are heard most distinctly.