McNamara et al used 4 clinical parameters (1 historical, 1 radiologic, 1 from the ECG, 1 laboratory test) to predict if the left ventricular ejection fraction (LVEF) was > 0.40. This is a simple assessment that can be performed without complex equipment. The authors are from the University of Rochester in New York.
Parameters:
(1) location of the acute infarct
(2) chest X-ray findings
(3) history of a previous myocardial infarction
(4) serum creatine kinase
|
Parameter |
Odds Ratio for LVEF <= 0.40 |
|
anterior MI |
4.7 |
|
pulmonary congestion on chest X-ray |
2.9 |
|
history of previous MI |
2.3 |
|
serum CK > 1,000 units |
2.1 |
from Table II, page 194
|
Parameter |
Finding |
Points |
|
location of the acute MI |
anterior |
1 |
|
|
other than anterior |
0 |
|
pulmonary congestion on chest X-ray |
present |
1 |
|
|
absent |
0 |
|
history of previous MI |
present |
1 |
|
|
absent |
0 |
|
serum CK |
> 1,000 units |
1 |
|
|
<= 1,000 units |
0 |
score =
= SUM(points for all 4 parameters)
Interpretation:
• minimum score: 0
• maximum score: 4
• The higher the score, the more likely that the LVEF was <= 0.40.
|
Score |
Accuracy |
|
0 or 1 |
80% for LVEF > 0.40 |
|
2, 3 or 4 |
72% for LVEF <= 0.40 |
Performance:
• Clinically significant major misclassifications were < 10%.
• Problems tended to occur for scores of 2, with these patients having a LVEF close to the breakpoint of 0.40 (page 195)
Limitations:
• The methodology and normal range for the serum CK is not given. By any method this would be indicate a sizable infarct.
Specialty: Cardiology
ICD-10: ,
