Wang et al reported a nomogram for predicting the need for percutaneous coronary intervention (PCI) in a patient with coronary artery disease. This can help to identify a patient likely to beneift from the procedure. The authors are from Ningbo University in China.
Patient selection: coronary artery disease
Parameters:
(1) lipoprotein A in g/L, from 0 to 1.2
(2) history of alcohol consumption
(3) serum potassium in mmol/L, from 2.6 to 4.6
(4) plasma fibrinogen in g/L, from 1 to 9
(5) diabetes
(6) serum ALT in U/L, from 0 to 600
(7) WBC in 10^9/L, from 2 to 18
(8) glycated serum protein (GSP) in mmol/L, from 1 to 4
(9) serum LDH in U/L, from 100 to 1,100
(10) high-sensitivity serum troponin C as normal or high
(11) absolute neutrophil count in 10^9/L, from 0 to 16
(12) blood glucose in mmol/L, from 2 to 20
points for ALT =
= 59.5 - (0.091 * (ALT))
points for fibrinogen =
= (2.4 * (fibrinogen)) + 46.8
points for glucose =
= (3.45 * (glucose)) + 36.2
points for GSP =
= 77.1 - (10.5 * (GSP))
points for potassium =
= (4.8 * (potassium)) + 37.52
points for LDH =
= (0.02 * (LDH)) + 49.45
points for lipoprotein a =
= (6.9 * (lipoprotein)) + 54.9
points for absolute neutrophil count =
= 73.2 - (3.7 * (ANC))
points for WBC =
= (2.1 * (WBC)) + 41.6
|
Parameter
|
Finding
|
Points
|
|
alcohol consumption
|
no
|
56.6
|
|
|
yes
|
60.2
|
|
diabetes
|
no
|
56.6
|
|
|
yes
|
64
|
|
hs troponin C
|
normal
|
56.6
|
|
|
high
|
72.1
|
where:
• The text says that serum fructosamine is a risk factor but it is not included in the nomogram.
• The text does not mention glycated serum protein as a risk factor but it appears in the nomogram. Commonly used units for GSP are µmol/L.
total score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score: 518.4
• maximum score: 844
value of X =
= (0.17 * (score)) - 114.2
probability of needing PCI =
= 1 / ( 1 + EP((-1) * X))
Performance:
• The C-index is 0.84.
