Myocardial Infartion with left dominant coronary circulation - 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 03-23-2012
Hope2Pass's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,684
Threads: 213
Thanked 1,590 Times in 660 Posts
Reputation: 1600
Heart Myocardial Infartion with left dominant coronary circulation

A 68-year-old man sustains a myocardial infarct resulting from thrombotic occlusion at the origin of the left circumflex artery. Cardiac catheterization demonstrates that the patient has a left dominant coronary circulation. In which of the following areas of the heart has ischemic necrosis most likely occurred?

A) Apex of left ventricle and anterior portion of septum
B) Lateral left ventricular wall and posterior portion of the septum
C) Lateral wall of the left ventricle only
D) Posterior portion of the septum only
E) Right ventricular wall
Reply With Quote Quick reply to this message



  #2  
Old 03-23-2012
beka-CTS's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 763
Threads: 77
Thanked 1,338 Times in 347 Posts
Reputation: 1348
Default

i would go with B
__________________
Step 1 - 244 [✔] Step 2 CK - 246 [✔] Step 2 CS [✔] Step 3 - 228 [✔] Match [EMORY SOM] YOG: 2013, 4 Months of USCE University Hospital
Reply With Quote Quick reply to this message
  #3  
Old 03-23-2012
DocSikorski's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,353
Threads: 94
Thanked 873 Times in 506 Posts
Reputation: 886
Default

Its B

Heart is totally my thing
__________________
Ambition is a dream with a V8 engine. EP
Reply With Quote Quick reply to this message
  #4  
Old 03-23-2012
USMLE Forums Scout
 
Steps History: Step 1 Only
Posts: 44
Threads: 4
Thanked 5 Times in 5 Posts
Reputation: 15
Default

B) Lateral left ventricular wall and posterior portion of the septum
Reply With Quote Quick reply to this message
  #5  
Old 03-23-2012
USMLE Forums Addict
 
Steps History: Step 1 Only
Posts: 177
Threads: 33
Thanked 85 Times in 16 Posts
Default

It's B.........:
Reply With Quote Quick reply to this message
  #6  
Old 03-23-2012
Hope2Pass's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,684
Threads: 213
Thanked 1,590 Times in 660 Posts
Reputation: 1600
Default

The correct answer is B. A right dominant coronary circulation is present when the posterior descending branch originates from the right coronary artery (80% of individuals). On the contrary, the posterior descending artery originates from the left circumflex artery in a left dominant circulation (20% of individuals). The posterior descending branch gives blood to the posterior half of the interventricular septum. Occlusion of the left circumflex artery in a left dominant circulation will therefore lead to ischemic necrosis in the left ventricular wall and the posterior interventricular septum.

The apex of the left ventricle (choice A) is dependent on the anterior descending branch; thus, occlusion of the left circumflex does not affect this portion of the left ventricle.

Infarction of the lateral (free) wall alone (choice C) will result from occlusion of the circumflex in a right dominant circulation.

An isolated infarct of the posterior interventricular septum (choice D) arises from occlusion of the posterior descending branch.

Isolated infarcts of the right ventricular wall (choice E) are very rare and would be caused by occlusion of branches of the right coronary artery.
Reply With Quote Quick reply to this message



Reply

Tags
Anatomy-, Cardiovascular-, Step-1-Questions

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
subendocardial infarction Vs transmural infartion usmlemydream USMLE Step 1 Forum 4 03-14-2012 12:08 AM
Brain biopsy showed a few lacunas in the centrum semiovale, left basal ganglia, and left internal capsule Evergreen USMLE Step 1 Forum 4 11-11-2011 09:35 PM
pulmonary circulation winner21 USMLE Step 1 Forum 1 08-23-2011 07:26 PM
The Hemoglobin Disocciation Curve After return of circulation fin-84 USMLE Step 1 Forum 4 11-04-2010 06:55 AM
Peripheral Circulation and the Pressure between two points? Kabutar111 USMLE Step 1 Forum 2 07-31-2010 03:18 PM

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)