Timing of Gross and Microscopic changes in MI with clinical correlations - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     Members     Posts
USMLE Articles
Go Back   USMLE Forums > USMLE Step 1 Forum > USMLE Step 1 High Yield > USMLE Step 1 Bits & Pieces

USMLE Step 1 Bits & Pieces High yield short focused points, monographs, charts, illustrations, tables, and other stuff related to the USMLE Step 1 Exam.

Thread Tools Search this Thread Display Modes
Old 01-25-2011
USMLE Forums Addict
Steps History: 1 + CK
Posts: 117
Threads: 22
Thanked 28 Times in 15 Posts
Reputation: 38
Heart Timing of Gross and Microscopic changes in MI with clinical correlations

1- 4 hour
Gross: None for 1st 12 hours by direct examination.
Micro: None or wavy fibers. Contraction bands, when present, can occur early (as early as after 2 minutes of reperfusion in animal experiments). .
Clinical: Mural thrombi
can form early and embolize at any time

4-12 Hour
Gross: Special staining shows lack of dehydrogenase, dark mottling
Micro: Early coagulation necrosis
, edema, hemorrhage, Earliest sign is hypereosinophilia of myocytes.
Clinical: CK and CK-MB elevated 4-48 hours. Troponin I 3-12 hrs

12-24 Hour

Gross: Coagulation necrosis
Micro: Pyknosis, neutrophils begin to enter area of infarction.

Clinical: Serious arrhythmias can occur at any time. Primary ventricular fibrillation usually in 1st 12 hours.

1-3 Days
Gross: Pallor of infracted tissue
Micro: loss of nuclei, loss of striations, neutrophils are abundant & lyse dead myocardial cells.
Clinical: Pericardial friction rub, due to fibrinous pericarditis, most common on days 2-3

3-7 days
Gross: macrophages and necrotic tissue predominate, tissue becomes soft
appears yellow with red border due to hyperemia.
Micro: Macrophages begin to remove necrotic debris
Clinical: Rupture of free wall, ventricular septum, or papillary muscle at 3-6 days

7-10 Days
Gross: Classic appearance of bright yellow infarct area surrounded by red granulation tissue
Micro: Necrotic area is bright yellow Granulation tissue & Collagen fibers are well developed
Clinical: Dressler syndrome
, an autoimmune-based pericarditis, at 1-8 weeks

2 Months
Gross: Appearance evolves to that of a white, fibrous, non contractile scar.
Miroc: Increased collagen and decreased cellularity.
Clinical: Ventricular aneurysms
are a late complication.
Reply With Quote Quick reply to this message
The above post was thanked by:
bruni (04-04-2011), dinosaur108 (10-17-2011), dr z (01-25-2011), dr.digant (06-11-2011), GNND85 (01-25-2011), mle_vrp (11-17-2011), Mondoshawan (01-25-2011), nushu2705 (01-25-2011), safa bm (01-26-2011), seraevening (01-25-2011)

Old 01-25-2011
USMLE Forums Scout
Steps History: Step 1 Only
Posts: 82
Threads: 4
Thanked 80 Times in 30 Posts
Reputation: 90
Thumbs Up thanks

Awesome post
Reply With Quote Quick reply to this message
Old 01-25-2011
USMLE Forums Newbie
Steps History: Not yet
Posts: 4
Threads: 0
Thanked 7 Times in 2 Posts
Reputation: 17
Default thanks!

very helpful!
Reply With Quote Quick reply to this message
Old 04-04-2011
USMLE Forums Newbie
Steps History: Not yet
Posts: 1
Threads: 0
Thanked 0 Times in 0 Posts
Reputation: 10

very helpful and concise thank you
Reply With Quote Quick reply to this message


Cardiovascular-, Pathology-

Quick Reply

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:
Please enter a password for your user account. Note that passwords are case-sensitive.
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.
Where you live. Leave blank if you don't want to tell.


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
Ovarian Tumor Gross Pathology! Farqad USMLE Step 2 CK Forum 6 04-11-2016 06:20 AM
Microscopic Changes In Sequence After Cerebral Infarction! anila USMLE Step 1 Mnemonics 0 12-25-2010 09:04 PM
BRS test on gross anatomy, help amen.h31 USMLE Step 1 Forum 1 11-20-2010 03:20 PM
Microscopic Hematuria in African American Woman? mtoi USMLE Step 1 Forum 4 11-09-2010 04:52 AM
How important is Gross anatomy for step 1? sonam88 USMLE Step 1 Forum 6 09-25-2010 02:34 PM

RSS Feed
Find Us on Facebook
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2016 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)