NOTE: This tool should only be used as a guide by a trained clinician.

Clinical assessment of likelihood of Coronary Artery Disease (CAD) in patient presenting with Stable Chest Pain
based on NICE Clinical Guideline 95 (May 2010), and ACC/AHA 1999 guidelines:Diamond & Forrester, Pryor (Duke University)
West Hertfordshire Cardiology

Likelihood of having CAD as cause of presenting Chest Pain, using Clinical Variables

This score is not applicable if patient is already known to have CHD

     Age    (original calculations derived from patients aged 35-70)    years
     Sex Male Female
 Characteristics of presenting Chest Pain 1-3,6 Yes No
 1   Constricting discomfort in the front of the chest, or in the neck, shoulders, jaw, or arms
 2   Precipitated by physical exertion
 3   Relieved by rest or GTN (within about 5 minutes)/
= Categorisation of Chest Pain 


 Clinical Risk variables 4-6 Yes No
      Current Smoker
      Total Cholesterol > 6.5 mmol/l (>250 mg/dl)
      Previous MI
      ECG: Q waves of old MI
      ECG: ST changes at rest
= Likelihood of patient having significant* CAD 5,6 
  *>75% stenosis of at least 1 major coronary artery  

In a patient presenting with stable chest pain, the likelihood of significant underlying Coronary Artery Disease (CAD) can be determined quite accurately from simple systematic clinical evaluation.

Stable Angina is:

     1. Constricting discomfort in the front of the chest, or in the neck, shoulders, jaw, or arms

     2. Precipitated by physical exertion

     3. Relieved by rest or GTN within about 5 minutes


Use clinical assessment and the typicality of anginal pain to estimate the likelihood of CAD

     3 of the features above               = Typical angina

     2 of the 3 features above            = Atypical angina

     1 or none of the features above  = Non-anginal chest pain


If chest pain is non-anginal, exclude a diagnosis of stable angina.

 - first consider causes of chest pain other than angina caused by CAD (such as gastrointestinal or musculoskeletal pain).


If chest pain is atypical or typical angina and likelihood of CAD is 10-90%, further diagnostic investigation is necessary.

     - Do not use exercise ECG to diagnose or exclude stable angina for people without known CAD


If chest pain is typical angina and likelihood of CAD is >90% further diagnostic investigation is unnecessary.  Manage as angina.

(But invasive angiography is still often necessary, not specifically for diagnosis, but to plan any revascularisation strategy).


1   Gibbons RJ et al.
ACC/AHA/ACP-ASIM Chronic Stable Angina Guidelines
JACC 1999;33:2092–197
2 Diamond GA, Forester JS.
Analysis of probability as an aid in the clinical diagnosis of coronary-artery disease.
NEJM 1979;300:1350-8
3 Chaitman BR et al.
Angiographic prevalence of high-risk coronary artery disease in patient subsets (CASS)
Circulation 1981;64:36-7

Pryor DB et al (from Duke University)
Estimating the likelihood of significant coronary artery disease
Am J Med 1983;75:771-80

Initial risk scoring function

Training sample n=3627, Validation sample n=1811  Study dataset n=5438 (67% had significant CHD at Angio)


Pryor DB et al (from Duke University)
Value of the history and physical in identifying patients at increased risk for CAD
Ann Int Med 1993;118:81-90

Later reworking of risk function

Study dataset n=1030 (168 had angio within 90 days, 109 had significant CHD. 90% of pts with significant CHD had predicted risk>44%, 62% of pts without significant CHD had predicted risk<44%) (c-index 0.87, meaning the model correctly ranks patients 87% of the time)

6   NICE Clinical Guideline 95  (May 2010)

Page designed by and © Dr John Bayliss - West Herts Cardiology  2010 v2