Prevalence
Clinical
features
Differential
diagnosis
Investigations
Therapy
Prevention
Prognosis
|  | | | Investigations |
Less helpful alternatives include
-
troponin T a
b
c
or troponin I
c
Why?
A normal troponin T at 20 hours makes an MI unlikely
| Patient c
|
Target Disorder and
Reference Standard |
Diagnostic Test |
LR+
(95% CI)
|
Post-test Probability |
LR-
(95% CI)
|
Post-test Probability |
suspected myocardial infarction
(pre-test probability: 18%)
|
myocardial infarction
(history, ECG, CK-MB
act
)
|
elevated troponin T at 3 hours after symptom onset
|
6
(4 to 9)
|
57% |
0.67
(0.59 to 0.76)
|
13% |
|
|
|
at 4 hours
|
11
(7 to 16)
|
71% |
0.59
(0.52 to 0.67)
|
9% |
|
|
|
at 6 hours
|
7
(4 to 10)
|
61% |
0.37
(0.31 to 0.43)
|
8% |
|
|
|
at 8 hours
|
9
(6 to 13)
|
66% |
0.23
(0.19 to 0.27)
|
5% |
|
|
|
at 12 hours
|
9
(7 to 12)
|
66% |
0.078
(0.064 to 0.94)
|
2% |
|
|
|
at 20 hours
|
9
(6 to 13)
|
66% |
0.022
(0.019 to 0.027)
|
0.5% |
Normal CK-MB and troponin I can help rule out MI
| Patient c |
Target Disorder and
Reference Standard |
Diagnostic Test |
LR+
(95% CI)
|
Post-test Probability |
LR-
(95% CI)
|
Post-test Probability |
chest pain lasting for at least 15 minutes within previous 24 hours
(pre-test probability: 37%)
|
myocardial infarction
(CK-MBmass at 24 hours)
|
troponin I at 6 hours
|
10
(7.3 to 14)
|
59% |
0.45
(0.37 to 0.56)
|
6% |
|
|
|
at 18 hours
|
15
(11 to 19)
|
67% |
0.045
(0.019 to 0.11)
|
1% |
Note
- Adding troponin T to routine clinical examination, serial ECGs and
CK-MB does not reduce time in the emergency department or in hospital
if admitted. d
|
internal medicine