Aortic Dissection is due to defect in which of these? - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     Members     Posts
Home
USMLE Articles
USMLE News
USMLE Polls
USMLE Books
USMLE Apps
Go Back   USMLE Forums > USMLE Step 1 Forum

USMLE Step 1 Forum USMLE Step 1 Discussion Forum: Let's talk about anything related to USMLE Step 1 exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 02-26-2011
USMLE Forums Scout
 
Steps History: Step 1 Only
Posts: 48
Threads: 30
Thanked 37 Times in 14 Posts
Reputation: 47
Question Aortic Dissection is due to defect in which of these?

a pt presents with aortic dissection. it is due to a defect in which of the following?
a. elastin
b. fibrillin
c. fibronectin
d. integrin
e. laminin
Reply With Quote Quick reply to this message
The above post was thanked by:
drgabroomunda (02-27-2011), Taiwan_Guy (05-19-2011)



  #2  
Old 02-26-2011
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,175
Threads: 38
Thanked 852 Times in 478 Posts
Reputation: 862
Default

I will guess A) Elastin
Reply With Quote Quick reply to this message
  #3  
Old 02-26-2011
USMLE Forums Scout
 
Steps History: Not yet
Posts: 26
Threads: 10
Thanked 88 Times in 24 Posts
Reputation: 98
Default

Patient with Marfan syndrome is at risk for Aortic dissection.
Marfan syndrome has mutation at fibrillin so I'll go with fibrillin

INTRAMURAL AORTIC HEMATOMA AND AORTIC DISSECTION
Definition
An intramural aortic hematoma occurs when bleeding from the vasa vasorum causes a hematoma within the aortic media. Aortic dissection occurs when the media of the blood vessel is cleaved longitudinally to form a false lumen that communicates with the true lumen.
The location of an intramural aortic hematoma or dissection may be described according to one of several classification systems .
Two thirds of aortic dissections are type A (proximal) and the other third are type B (distal). The classification schemes all serve the same purpose, which is to distinguish dissections that involve the ascending aorta from dissections that do not. Involvement of the ascending aorta carries a high risk for early rupture and death from cardiac tamponade, so the prognosis and management differ according to the extent of aortic involvement. Hematomas and dissections are also classified according to their duration: less than 2 weeks is considered acute, whereas 2 weeks or more is considered chronic.

Aortic Dissection is due to defect in which of these?-figure-1.jpg
click image to enlarge

The peak incidence of aortic dissection in patients without Marfan syndrome is in their 60s and 70s, and men are affected twice as often as women. A history of hypertension is present in most cases, whereas a bicuspid aortic valve or known preexisting thoracic aortic aneurysm is less common. Rarely, aortic dissection may occur in a young woman during the peripartum period. Iatrogenic trauma from intra-aortic catheterization procedures or cardiac surgery may also cause aortic dissection.
Pathobiology
Disease of the aortic media, with degeneration of the medial collagen and elastin, is the most common predisposing factor for aortic dissection. Patients with Marfan syndrome have classic cystic medial degeneration and are at particularly high risk for aortic dissection at a relatively young age. Aortic dissection classically begins either with a tear in the aortic intima, thereby exposing the diseased medial layer to the systemic pressure of intraluminal blood, or with an intramural hematoma caused by bleeding in the vasa vasorum of the arterial wall. This hematoma may propagate longitudinally along a variable length of the aorta. If the intimal layer remains intact, the hematoma does not communicate with the aortic lumen, but if it does, it will become no different than a dissection that began with an intimal tear. The result will be cleavage of the media into two layers longitudinally, thereby producing a blood-filled false lumen within the aortic wall. This false lumen propagates distally (or sometimes retrogradely) a variable distance along the aorta from the site of the intimal tear.
MARFAN SYNDROME
Definition Marfan syndrome is an autosomal dominant, pleiotropic disorder caused by defects in the principal component of the extracellular microfibril, the large glycoprotein fibrillin-1. The disease manifestations occur in multiple systems, especially the eye, skeleton, heart, aorta, lung, and integument. Notable features include dislocation of the ocular lens, tall stature with particularly long limbs and digits, deformity of the thoracic cage from pectus carinatum or excavatum with abnormal curvature of the spine, mitral and tricuspid valve prolapse, dilation of the sinuses of Valsalva and predisposition to aortic dissection, spontaneous pneumothorax, abnormal skin stretch marks, hernias, and dural ectasia. If untreated, patients often die before 30 or 40 years of age from aortic dissection or congestive heart failure.
Reply With Quote Quick reply to this message
The above post was thanked by:
aktorque (02-26-2011), donofitaly (02-26-2011), drgabroomunda (02-27-2011), Sana Zahid (02-26-2011), Taiwan_Guy (05-19-2011), wimzie (02-28-2011)
 
  #4  
Old 02-26-2011
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,175
Threads: 38
Thanked 852 Times in 478 Posts
Reputation: 862
Default

Quote:
Originally Posted by Taiyakikung View Post
Patient with Marfan syndrome is at risk for Aortic dissection.
Marfan syndrome has mutation at fibrillin so I'll go with fibrillin
Fibrillin 1 protein is needed for formation of Elastin. Which is the major component of the artery for structural integrity of connective tissue.

Reply With Quote Quick reply to this message
The above post was thanked by:
aktorque (02-26-2011), Taiwan_Guy (05-19-2011)
  #5  
Old 02-26-2011
USMLE Forums Guru
 
Steps History: Step 1 Only
Posts: 487
Threads: 95
Thanked 1,459 Times in 357 Posts
Reputation: 1469
Arrow

Quote:
Originally Posted by Taiyakikung View Post
Patient with Marfan syndrome is at risk for Aortic dissection.
Marfan syndrome has mutation at fibrillin so I'll go with fibrillin
Man.. that was a huge post.... but excellent information... Thankz
Reply With Quote Quick reply to this message



Reply

Tags
Cardiovascular-, Figures-, Pathology-, Step-1-Questions, Syndromes-Acronyms

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the USMLE Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Medical School
Choose "---" if you don't want to tell. AMG for US & Canadian medical schools. IMG for all other medical schools.
USMLE Steps History
What steps finished! Example: 1+CK+CS+3 = Passed Step 1, Step 2 CK, Step 2 CS, and Step 3.

Choose "---" if you don't want to tell.

Favorite USMLE Books
What USMLE books you really think are useful. Leave blank if you don't want to tell.
Location
Where you live. Leave blank if you don't want to tell.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Leukocyte Adhesion Defect Types? drsmar USMLE Step 1 Forum 2 03-20-2012 08:36 PM
T cell defect anoop_1198 USMLE Step 2 CK Forum 6 05-25-2010 10:49 PM
Ventricular Septal Defect Association Mnemonic corpus callosum USMLE Step 2 CK Mnemonics 0 05-17-2010 02:54 PM
Heart Defect after Cancer HouseWannabe USMLE Step 1 Forum 6 04-21-2010 09:08 AM
Aortic stenosis FSUSTC USMLE Step 2 CK Mnemonics 0 03-23-2010 06:41 AM

RSS Feed
Find Us on Facebook
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

USMLE® & other trade marks belong to their respective owners, read full disclaimer
USMLE Forums created under Creative Commons 3.0 License. (2009-2014)