pc

ARC

    
       
       
    Atherosclerosis  
    Risk  
    Calculator  
       
    Calculator for Posttest Risk using SCORE as the pretest measure and Carotid Total Plaque Area as the Corrector for SCORE.  
 

 

   by Michel Romanens and Franz Ackermann, MDs back to main page
    published 15. March 2004 (older version are not valid any more !)  
       
   

These Risk Tables include atherosclerosis imaging of the carotid arteries expressed as the total plaque area. They allow to calculate various risks like fatal or nonfatal stroke, fatal or nonfatal myocardial infarction, fatal stroke and myocardial infarction ecc.

We recommend to calculate the combined endpoint of fatal stroke or myocardial infarction with the SCORE value as the pretest probability. We keep in mind, that TPA works better for vascular mortality (ROC 0.77) than e.g. for fatal and nonfatal myocardial infarction (ROC 0.53). TPA is at least equivalent to predict fatal cardiovascular events when compared to SCORE.

  
     
       
    1. Step: enter pretest probability for fatal stroke or myocardial infarction (derived from the new European Guides SCORE) into the yellow field  
    2. Step: Select in the yellow field for fatal stroke or MI an appropriate cutpoint dividing the values of the carotid total plaque area into "Test -" (left side) and "Test +" (on the right side of the cutpoint) and click the boutton "fatal stroke or MI", which will immediately produce the results in step 3.  
      3. Step: read results for positive and negative test on the right bottom  
      4. Step: in subjects with posttest risk of 2.0-4.9% an additional coronary calcium score should be obtained in order to filter out subjects with high coronary risk.  
         

2. Step

                   

select an appropriate cutpoint declearing TPA values on his right side as "Test +", then click on the field "Fatal Stroke or MI" just below and then go to step 3.

  Risk

 

    

 

        

 

    
  Low - cut + Interm - cut + High - cut + Very High Best cut Incidence Ref in German

TPA

0.00 - 0.11
Risk 0.237%

 TPA

0.115

 TPA

0.12 - 0.45
Risk 1.18%

TPA

0.455

 TPA

0.46 - 1.18
Risk 1.90%

 TPA

1.185

TPA

1.19 - 6.73
Risk 7.16%

 TPA

1.025

 2.61 %
/2.5 Jahre		 Spence
Spence JD et al. Carotid Plaque Area. Stroke. 2002;33:2916-2922                     Risk 0.00 - 0.11
6.4 %		 0.115
 0.12 - 0.45
11.3 %		 0.455
 0.46 - 1.18
13.2 %		 1.185
 1.19 - 6.73
19.1 %		 ? 12.51 %
/ 5 Jahre		 Spence
0.00 - 0.11
1.18 %		 0.115
 0.12 - 0.45
1.89 %		 0.455
 0.46 - 1.18
3.80 %		 1.185
 1.19 - 6.73
4.53 %		 0.695
 2.85 %
/2.5 Jahre		 Spence
0.00 - 0.11
3.79 %		 0.115
 0.12 - 0.45
7.55 %		 0.455
 0.46 - 1.18
6.18 %		 1.185
 1.19 - 6.73
9.79 %		 0.475
 6.82 %
/2.5 Jahre		 Spence

1. Step

Enter Pretest-Risk

(e.g. 3 = 3%)

into the bottom field

Endpoints

3. Step

Read Endpoint Value Here

Upper Value for Test Positivity

Lower Value for Test Negativity

 
Pretest-Risk
%

LR+   [95% CI]

LR -   [95% CI]

Posttest-Risk if test  positive
%

Posttest-Risk if test  negative
%

       Score for pretest likelihood
CVD-Risk Calculator , designed by Romanens + Ackermann, CH-4600 Olten
Bayes2_Stufendiagnose_IENS_ARC.html, Version 2.0
26th February 2004
revised 11th November 2006