5 doctors weighed in:
Can you explain why we can hear better the diastolic murmur of mitral stenosis during expiration?
5 doctors weighed in

Dr. Aaron Milstone
Internal Medicine - Pulmonology
2 doctors agree
In brief: Venous Return
In general when you expire (breath out) you decrease the amount of venous return to the right side of the heart but increases blood volume going to the left heart.
Left sided murmurs will increase in intensity with expiration and right sided murmurs will increase in intensity/sound with inspiration.

In brief: Venous Return
In general when you expire (breath out) you decrease the amount of venous return to the right side of the heart but increases blood volume going to the left heart.
Left sided murmurs will increase in intensity with expiration and right sided murmurs will increase in intensity/sound with inspiration.
Dr. Aaron Milstone
Dr. Aaron Milstone
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1 comment
Dr. Louis Grenzer
In addition, when you breath out, there is less air between the stethoscope and the heart so that a murmur or sound will be louder. In the case of right sided murmurs, this still applies, but the increase in loudness due to increased flow usually outweighs the "closeness to the heart" effect.
Dr. Howard Rubin
Internal Medicine - Cardiology
1 doctor agrees
In brief: Murmur
Heart is closer to the chest wall.

In brief: Murmur
Heart is closer to the chest wall.
Dr. Howard Rubin
Dr. Howard Rubin
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