Louise Cullen and Rick Body fuel a contentious debate on the clinical significance of the high sensitivity troponin assay. Will your patients benefit from that extra digit ?

1. HIGH SENSITIVITYTROPONIN INTHE
EMERGENCY DEPARTMENT:
FRIEND OR FOE?
Rick Body

2. DISCLAIMER
What I say is not necessarily my personal opinion.
COI: Expert adviser to NICE, active researcher in this area (including industry supported work)
Image by RedHotHeat via Wikimedia Commons

3. HIGH SENSITIVITYTROPONIN READS HIGHER
So you get more positives
10ng/L
Standard troponin
HS-troponin
35ng/L14ng/L

4. Chest pain
Collapse
SOB
"Unwell"
0 17.5 35 52.5 70
34.4
68.4
36.5
20.4
12.2
19.8
11.1
10.5
Before hs-Tn After hs-Tn
0
20
40
60
80
All Age >75
74
32 30
18
Before hs-Tn After hs-Tn
Proportion of positive
results before & after
introducing hs-cTnT

5. ANSWER: 50%
If your patient with suspected ACS has a
positive troponin, what is the overall
probability that they have AMI?
Image by anieto2k on Flickr..comBody et al, JACC 2011; 58: 1332-9

6. WHY DO WE NEED A HIGH SENSITIVITY
ASSAY?

7. SO WE CAN SEE LEVELS IN NORMAL PEOPLE
Because that's so helpful in practice, right?

8. 2. BECAUSETHE
RESULTS ARE MORE
PRECISE
With a 25% CV instead of 10%:
An extra 0.3% of patients will have a false
positive result after 2 tests
!
"We believe that the clinical implications of
this false positive frequency are
insignificant"
Apple et al, Clin Chem 2005; 51:2198-2200

9. WHAT’STHE EVIDENCE OF BENEFIT?

11. I REST MY CASE, M'LUD
May justice be done