Body et al developed the Manchester Acute Coronary Syndrome (MACS) decision rule to evaluate a patient with acute chest pain. This was revised to use troponin as the only serum biomarker. The authors are from the University of Manchester, Southmead Hospital Bristol, Stockport NHS Foundation Trust, Manchester Metropolitan University and University of the Sunshine Coast in Australia.
Patient selection: an adult in the Emergency Department (ED) with suspected cardiac chest pain
Outcome: 30-day major adverse cardiac event (MACE = death, acute myocardial infarction, need for coronary revascularization or new coronary stenosis > 50%)
The original MACS rule included heart-type fatty acid binding protein (FABP, Randox Evidence Investigator Cardiac Array) which is not always readily available.
Parameters:
(1) high sensitivity serum troponin T in ng/L (Roche Diagnostics), with 99th percentile 14 ng/L
(2) ECG ischemia
(3) sweating observed
(4) vomiting
(5) systolic blood pressure in mm Hg
(6) worsening or crescendo angina (increasing frequency, with less exertion, more prolonged)
(7) pain radiating to the right arm or shoulder
Parameter
|
Finding
|
Points
|
serum troponin
|
|
0.089 *
|
ECG ischemia
|
no
|
0
|
|
yes
|
1.713
|
sweating
|
absent
|
0
|
|
present
|
2.058
|
vomiting
|
no
|
0
|
|
yes
|
1.417
|
systolic blood pressure
|
>= 100 mm Hg
|
0
|
|
< 100 mm Hg
|
1.208
|
worsening angina
|
no
|
0
|
|
yes
|
0.847
|
radiating pain
|
no
|
0
|
|
yes
|
0.607
|
X =
= SUM(points for all 7 parameters) - 4.766
probability of MACE =
= 1 / (1 + EXP((-1) * X))
Interpretation:
• A patient identified as very low risk may be considered for discharge from the ED.
Performance:
• The area under the ROC curve was 0.90.