Daly et al developed a risk score for predicting the risk of death or myocardial infarction within 1 year for a patient with stable angina. This can help identify patients who may benefit from closer monitoring or more aggressive management. The authors are from Royal Brompton Hospital and the London School of Hygiene and Tropical Medicine in London.
Parameters:
(1) comorbidity
(2) diabetes mellitus
(3) angina score (based on the Canadian Cardiovascular Society classification, see 37.06.03)
(4) duration of symptoms in months
(5) ventricular function
(6) resting ECG
Comorbidities include:
(1) previous cerebrovascular event (stroke, other)
(2) hepatic disease (cirrhosis, chronic hepatitis, elevation of transaminases >= 3 times upper limit of normal)
(3) peripheral vascular disease (claudication at rest or with exertion, amputation for arterial insufficiency, vascular surgery, aortic aneurysm, evidence of impaired arterial flow)
(4) chronic renal failure (chronic dialysis, renal transplantation, serum creatinine > 200 µmol/L or > 2.26 mg/dL)
(5) chronic respiratory disease (therapy with bronchodilator, FEV1 < 75% of predicted, PaO2 < 60%, PaCO2 > 50%)
(6) chronic inflammatory disease (rheumatoid arthritis, SLE, polymyalgia rheumatica, other connective tissue disease)
(7) malignancy (diagnosis of malignancy within 1 year or active malignancy)
Parameter |
Finding |
Points |
comorbidity |
none |
0 |
|
>= 1 |
86 |
diabetes mellitus |
absent |
0 |
|
present |
57 |
angina score |
Class I |
0 |
|
Class II |
54 |
|
Class III |
91 |
duration of symptoms |
>= 6 months |
0 |
|
< 6 months |
80 |
ventricular function |
normal |
0 |
|
abnormal |
114 |
resting ECG |
ST depression or T wave inversion |
34 |
|
neither |
0 |
where:
• A person with Class IV angina would not have stable disease.
total score =
= SUM(points for all 6 factors)
Interpretation:
• minimum score: 0
• maximum score: 462
• The higher the score the greater the risk of death and/or myocardial infarction within one year.
The table for converting score to risk is in Table 7, which is only available online (see bmj.bmjjournals.com/cgi/content-nw/full/332/7536/262/TBL7). The data when plotted in MINITAB can be approximated by 2 equations:
For scores from 0 to 250:
risk in percent as a whole number =
= (-0.000018 * ((score)^2)) + (0.008363 * (score)) + 0.5418
For scores from 250 to 462:
risk in percent as a whole number =
= (0.000001 * ((score)^3)) - (0.000357 * ((score)^2)) + (0.06531 * (score)) - 1.814
Specialty: Cardiology
ICD-10: ,