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Discussion Starter · #1 ·
which of the following pathophysiological changes may be most useful in documenting within less than 6 hrs, that a patient had a myocardial infarction?

a. inverted or biphasic T wave on ECG
b. elevated serum of CK-M3
c. elevated serum of myocardial LDH
d. maximal indices of coagulative necrosis
e. peak tissue infiltration of neutrophils.
 

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Okay... gonna take a shot at this one too:

a) I know inverted t waves are seen with myocardial ischemia but I'm not sure when, from what I remember it was 24 hours afterwards though - please correct me... :)

b)This would be my guess - CK-MB is elevated in the serum 4-8 hours after an MI reaching a peak at 18 hours so.

c) LDH takes about 24 hours to elevate so not c.

d) coagulative necrosis starts at about 6 hours, but maximal necrosis isn't complete till after 24 hours or so, so not d.

e) neutrophils come after coagulative necrosis starts so that would be even later and would not max out in the first 6 hours (typically 1-4 days)

So I'm going to guess B... let me know what you guys think!
 

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Discussion Starter · #3 ·
u have good a reasoning but unfortunately its not B.

anyone else wants to give it a go?:)

ashishkabir u are close. unless u just want the answer already?
 

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I wouldn't mind someone else double checking the times for me, actually, my source for this is not 100% reliable - it's a powerpoint file I found on pathology. I would share it, but since I'm not sure it's correct I wouldn't mind some help with this... Thanks guys!

Ashish
 

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Answer

A is correct.

Reference : BRS pathology (page 138)

In MI:
A) 0-6 h: Arrhythmias most common cause of death in early hours
B) CK-MB is weekly positive within 0-6 h after MI. It strongly positive at 12-16 h and peak at 24 hours.
C) LDH peaks 3 days after MI.
D) Well-developed changes of coagulative necrosis is by 24 hours.
E) First appearance of neutrophils in viable tissue adjacent to the lesion is after 12 hours.
 

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Always first go with ECG
if its negative than do enzyme work up ,CKMB
coagulative necrosis start within 4-12 hr after MI(kaplan qbank)
neutrophiles will start to infiltrate within 24 hr
 

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which of the following pathophysiological changes may be most useful in documenting within less than 6 hrs, that a patient had a myocardial infarction?

a. inverted or biphasic T wave on ECG
b. elevated serum of CK-M3
c. elevated serum of myocardial LDH
d. maximal indices of coagulative necrosis
e. peak tissue infiltration of neutrophils.
a. inverted or biphasic T wave on ECG
 
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