Unstable angina (UA) most commonly presents with chest pain and/or dyspnea, although atypical symptoms may be present.
Initial risk stratification and management depends on the clinical features, ECG, and biomarkers (troponin).
ECG typically shows ST segment depression and T-wave inversion; may show transient ST elevation, or may be normal.
Acute management includes antiplatelet and antithrombotic therapy to reduce the extent of myocardial damage and complications.
Long-term management includes reduction of risk factors and use of medication to prevent recurrence.
UA is an acute coronary syndrome that is defined by the absence of biochemical evidence of myocardial damage. It is characterized by specific clinical findings of prolonged (>20 minutes) angina at rest; new onset of severe angina; angina that is increasing in frequency, longer in duration, or lower in threshold; or angina that occurs after a recent episode of myocardial infarction.
History and exam
Key diagnostic factors
- increasing frequency of chest pain
- increasing severity of chest pain
- retrosternal chest pain radiating to jaw, arm, or neck
- fourth heart sound (S4)
Other diagnostic factors
- atypical chest discomfort
- carotid bruit
- diminished or absent peripheral pulses
- third heart sound (S3)
- female sex
- personal history of coronary artery disease (CAD)
- increased age
- family history of CAD
- diabetes mellitus
- peripheral vascular disease
- chronic kidney disease
- elevated C-reactive protein levels
- mediastinal radiation
- obesity/lack of exercise
1st investigations to order
- cardiac biomarkers
- electrolytes and renal function
- blood sugar
- lipid profile
- coagulation profile
- echocardiogram: rest
- myocardial perfusion study: rest
- CT chest or MRI
- coronary angiography
Investigations to consider
- echocardiogram: stress
- myocardial perfusion study: stress
- coronary CT angiography
presumed cardiac chest pain
non-ST-elevation acute coronary syndrome
confirmed UA (nonelevated cardiac biomarkers)
- Stable angina
- Prinzmetal (variant or vasospastic) angina
- Non-ST-elevation myocardial infarction
- Guideline for the evaluation and diagnosis of chest pain
- Guideline for coronary artery revascularization
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