Where are S1 and S2 heard the loudest?

Intensity of S1 and S2: Normally, S1 is louder than S2 at the apex, and softer than S2 at the base of the heart.

Which is loudest S1 or S2?

The intensity of the first sound is greater than the second. In a normal heart S1 is louder than S2 in the apex, and S2 is louder than S1 in the base. Compare the sounds from apex to base of the heart. S1 is generated by closure of mitral and tricuspid valves and they are close to the apex of heart.

Where is S1 sound loudest?

the apex
The first heart sound has a booming quality and is lower-pitched, duller, and longer than the second heart sound. It is usually louder at the apex than is the second sound.

What causes loud S1 and S2?

The faster the heart rate and the faster the rise in ventricular pressure, the louder the S1.

Which heart sound is loudest?

Introduction to cardiac anatomy and physiology Normally the first (S1) and second (S2) heart sounds are loudest and are audible in all normal animals. S1 is audible at the onset of mechanical systole and occurs in association with closure of the atrioventricular valves.

Which of the two heart sounds is louder?

S1 – The first heart sound (lub) can be heard the loudest at the mitral area. This sound represents the closure of the mitral and tricuspid valves and is a low pitched, dull sound at the beginning of ventricular systole. S2 – The second heart sound (dub).

What causes loud second heart sound?

The loudness of each component of the second heart sound is proportional to the respective pressures in the aorta and pulmonary artery at the onset of diastole. Dilatation of the aorta or pulmonary artery may also cause accentuation of the aortic and pulmonic components, respectively.

Why is the first heart sound the loudest?

The first heart sound (S1) (Figure 1-9) is due to passive closure of the mitral (left AV) and tricuspid (right AV) valves resulting in the sudden acceleration and deceleration of blood. It has four parts that can be seen on a phonocardiogram. S1 is longer, louder, duller, and lower-pitched than the second heart sound.

Where is lub and dub loudest?

mitral area
Identify: S1 – The first heart sound (lub) can be heard the loudest at the mitral area. This sound represents the closure of the mitral and tricuspid valves and is a low pitched, dull sound at the beginning of ventricular systole. S2 – The second heart sound (dub).

Why is the second heart sound louder than the first?

The A2 sound is normally much louder than the P2 due to higher pressures in the left side of the heart; thus, A2 radiates to all cardiac listening posts (loudest at the right upper sternal border), and P2 is usually only heard at the left upper sternal border. Therefore, the A2 sound is the main component of S2.

Which heart valve is the loudest?

The M1 sound is much louder than the T1 sound due to higher pressures in the left side of the heart; thus, M1 radiates to all cardiac listening posts (loudest at the apex), and T1 is usually only heard at the left lower sternal border.

What does loud S1 mean?

Loud S1. This is the result of mitral valve leaflets remaining open at the end of diastole, rather than drifting back into a closed position as diastolic flow slows down. Such a wide-open mitral valve will slam shut loudly with the onset of systole, making the first heart sound louder than usual.