Causes of a Loud A2 or P2

1. What conditions tend to make the aortic component of the second sound louder than normal?

ANS: a. Conditions that raise aortic systolic pressure, e.g., systemic hyper tension, which occasionally produces a drumlike sound or "tambour" S2. A tambour is a small drum that is covered only on one side. The tambour effect may persist even after the blood pressure has been lowered to normal by medication.

b. Conditions that produce a hyperkinetic systemic circulation, e.g., youth, or thyrotoxicosis.

Aortic valve

Hyperkinetic Circulation
The root of the aorta with its aortic valve is behind the middle of the sternum.

Note: The loudness of the aortic closure depends on the recoil of the aorta and on ventricular performance [3]. It follows, then, that a hypertensive patient in heart failure may not have a loud A2.

2. What conditions, besides a thin chest wall and pulmonary hypertension, tend to make the P2 louder than normal?

ANS: Conditions that produce increased blood flow into the pulmonary artery, as in ASD or VSD.

3. Why does the A2 tend to be loud when the heart is hyperactive as in thyrotoxico-sis and aortic regurgitation (AR)?

ANS: The intensity of the A2 is increased if the aortic valve closes when the aorta is energetically recoiling from the violent stretch due to the increased volume flung into it during systole.

Note: With severe AR the A2 may be soft, presumably because of the absence of adequate valve substance to cause a sudden deceleration of forward flow.

4. How does inspiration affect the loudness of each component of the S2?

ANS: The P2 commonly becomes louder because extra blood in the pulmonary artery on inspiration causes more energetic elastic recoil. The A2, on the other hand, becomes softer because inspiration decreases the volume ejected into the aorta and also places the aorta farther from the stethoscope.

Note: All sounds tend to become softer on inspiration if you listen over the upper chest, where excess lung space is interposed between the stethoscope and the heart on inspiration.

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  • george white
    Why a2 is loud in hypertension?
    3 years ago
  • Duncan
    When we will hear loud p2?
    3 years ago
  • hamilcar
    How to determine loud p2?
    2 years ago
  • nicole
    Why aortic component is louder?
    2 years ago
  • oscar
    What is p2 accentuation?
    2 years ago
  • Arlene Holt
    Why loud a2 in aortic aneurysm?
    2 years ago
  • Joseph
    Is loud a2 a symptom of heart disease?
    2 years ago
  • valentin pappila
    How to confirm loud P2?
    2 years ago
  • Jasper
    Why does pulmonary hypertension cause louder s2?
    1 year ago
  • ali
    What is the differential diagnosis of loud s2?
    1 year ago
  • milla raila
    What is suggested by the loud p2?
    12 months ago
  • vernon
    What does a loud s2 mean for the ventricles?
    5 months ago
  • klaus
    Does a2 heart sound increase in pulmonary artery stenosis?
    4 months ago
  • daniel
    Is second hear sound louder in aortic regurgitation?
    4 months ago
  • Roxy Boyle
    Why does pulmonary hypertension give you a loud p2 and a parasternal lift?
    2 months ago
  • Ashlyn
    What causes loud s2 in the base of the heart?
    22 days ago
  • Sandra
    What does a loud s2 mean in the elderly?
    19 days ago

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