Kumar et al reported the RK-SF/NR (risk of slow flow or no re-flow) in a patient undergoing primary percutaneous coronary intervention (PCI). The authors are from the National Insitute of Cardiovascular Disease in Karachi, Pakistan.
Patient selection: primary percutaneous coronary intervention (PCI)
Outcome: slow flow or no re-flow
Parameters:
(1) sex
(2) total ischemic time in hours
(3) cardiac arrest at presentation
(4) left ventricular end-diastolic pressure (LV-EDP) in mm Hg
(5) left ventricular ejection fraction (LVEF) in percent
(6) culprit proximal left anterior descending artery
(7) thrombus grade (burden, from 0 to 5)
(8) pre-procedure TIMI (thrombolysis in myocardial infarction) flow (0, I, II or III)
(9) lesion length in mm
|
Parameter
|
Finding
|
Points
|
|
sex
|
male
|
0
|
|
|
female
|
2
|
|
total ischemic time
|
< 8 hours
|
0
|
|
|
>= 8 hours
|
1
|
|
cardiac arrest
|
no
|
0
|
|
|
yes
|
2
|
|
LV-EDP
|
< 24 mm Hg
|
0
|
|
|
>= 24 mm Hg
|
3
|
|
LVEF
|
> 30%
|
0
|
|
|
<= 30%
|
2
|
|
culprit proximal LAD
|
no
|
0
|
|
|
yes
|
3
|
|
thrombus grade
|
< 4
|
0
|
|
|
4 or 5
|
6
|
|
TIMI flow
|
0
|
2
|
|
|
> 0
|
0
|
|
lesion length
|
< 35 mm
|
0
|
|
|
>= 35 mm
|
3
|
total score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score: 0
• maximum score: 24
• A score >= 10 has a sensitivity of 0.78 and specificity of 0.63 for slow flow or no re-flow.
Performance:
• The area under the ROC curve is 0.78.
