1. Download free Tapatalk for iPhone or Tapatalk for Android for your phone and follow the SDN forums with push notifications.
    Dismiss Notice

Right-->left blood shunt

Discussion in 'Step I' started by Jane2005, Mar 2, 2007.

  1. Jane2005

    Jane2005 Member
    5+ Year Member

    Joined:
    Feb 2, 2005
    Messages:
    29
    Likes Received:
    0
    Does any know the pathophys involved R--> L blood shunt caused by pulmonary edema, pneumonia, and chronic liver disease ? These are listed as the possible causes of the shunt in a high yield book. Thanks
     
  2. Note: SDN Members do not see this ad.

  3. trudub

    trudub Senior Member
    7+ Year Member

    Joined:
    Oct 23, 2003
    Messages:
    337
    Likes Received:
    2
    Those would most likely be causes of reversing an L to R shunt to a R to L shunt. These conditions cause the pressure in the right side of the heart to increase and thus as right sided pressures exceed left sided pressures you reverse the shunt. As direct causes of an R to L shunt, I don't think those conditions you listed are direct causes.
     
  4. joe6102

    joe6102 by the power of grayskull
    5+ Year Member

    Joined:
    Mar 31, 2005
    Messages:
    396
    Likes Received:
    0
    Status:
    Resident [Any Field]
    In those two lung diseases, some alveoli are not ventilated, so blood flows from the right heart to the left heart without gas exchange, a physiological shunt (as opposed to anatomical shut such as ASD/VSD).
    In chronic liver disease, I'm not sure, but I think it has to do with high pressure in the portal system causes anastomoses, like caput medusa and esophageal varices. Not sure how that is a shunt though, because it should all end up in the right heart eventually.
     
  5. SeventhSon

    SeventhSon SIMMER DOWN
    7+ Year Member

    Joined:
    Aug 23, 2005
    Messages:
    1,022
    Likes Received:
    0
    MDApps:
    Status:
    MD/PhD Student
    by very poorly understood mechanisms, chronic liver disease patients may also have anastamoses at the level of the pulmonary artery --> vein, making an anatomic RL shunt (assumedly mediated by a growth factor that circulates in the blood in response to the disturbances in the liver)
     
  6. goodies

    goodies Member
    7+ Year Member

    Joined:
    Oct 8, 2005
    Messages:
    334
    Likes Received:
    0
    Status:
    Resident [Any Field]
    do you guys know what a left parasternal heave is? it is a sign of right ventricular hypertrophy, but i don't know what the heck "parasternal HEAVE" is... and why left instead of right?
     
  7. winsicle

    winsicle Member
    5+ Year Member

    Joined:
    Dec 15, 2004
    Messages:
    190
    Likes Received:
    0

    L parasternal = area that borders Left-side of sternum (i.e., around where the heart is located)

    Heave = while placing your hand over the area, the hand is actually lifted up off the chest due to an abnormally strong impulse from the heart (indicating RVH)
     
  8. Thievery Corp.

    Thievery Corp. Covert Hipster
    5+ Year Member

    Joined:
    Jul 16, 2006
    Messages:
    111
    Likes Received:
    0
    Status:
    Medical Student
    It's known as parasternal lift too. But "Heave" sounds so much more impressive.
     
  9. goodies

    goodies Member
    7+ Year Member

    Joined:
    Oct 8, 2005
    Messages:
    334
    Likes Received:
    0
    Status:
    Resident [Any Field]
    wow, that's interesting. didn't know that. thanks!!


    is accentuated p2 with pulm HTN the same thing as wide splitting with pulmonic stenosis?
     

Share This Page