Holter monitoring to detect paroxysmal atrial fibrillation can be performed in an adult who has had an ischemic stroke. Uphaus et al developed the AS5F score to identify a patient who should be selected for this testing. The authors are from multiple institutions in Germany and England.
AS5F = Age, NIHSS Score > 5, Find AF
Patient selection: status post ischemic stroke
Definition of atrial fbrillation: >= 1 period of > 30 seconds of an absolute arrhythmia without detectable P waves.
Parameters:
(1) age in years (maximum in nomogram 100)
(2) stroke severity by NIHSS
|
Parameter
|
Finding
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Points
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|
age in years
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|
0.76 * (age)
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|
stroke severity
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TIA
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0
|
|
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<= 5
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9
|
|
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> 5
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21
|
total score =
= SUM(points for the 2 parameters)
Interpretation:
• minimum score: depends on age, around 20
• maximum score: around 100
• A score >= 67.5 was associated with > 5.2% risk of atrial fibrillation.
• The number needed to screen was 100 divided by the percent risk.
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Score
|
|
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<34.8
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< 0.25%
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34.8 to 99.1
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(0.00030004 * ((score)^3)) - (0.040418 * ((score)^2)) + 1.8418 * (score)) - 27.559
|
|
> 99.1
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> 50%
|
Performance:
• The area under the ROC curve for prediction of pAF within a monitoring interval of 72 hours is 0.75.
