The following three patient groups may be said to have unstable angina pectoris.
- Patients with new onset (< 2 months) angina that is severe and/or frequent (>) 3 episodes/day
- Patients with accelerating angina, that is, those with chronic stable angina who develop angina that is distinctly more frequent, severe, prolonged or precipitated by less exertion than previously.
- Those with angina at rest.
- When unstable angina is accompanied by objective ECG evidence of transient myocardial ischaemia, this is associated with critical stenosis in one or more epicardial coronary arteries in about 85%.
