Chronic stable angina risk stratification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Cafer Zorkun, M.D., Ph.D. [2]; Smita Kohli, M.D.; Lakshmi Gopalakrishnan, M.B.B.S. ;Arzu Kalayci, M.D. [3]

Overview

The average mortality in patients with stable angina ranges from 1-3%. However, the prognosis varies widely depending on various factors such as: the duration and severity of symptoms, resting ECG abnormalities, abnormal left ventricular function and associated comorbidities.^[1]

Risk Stratification

Risk Stratification Based on Different Factors

Anatomic Factors

Left ventricular function, indicated as the strongest predictor of long term survival
Extent of atherosclerosis in the coronary arteries (single vessel disease vs multivessel disease)
Evidence of a recent coronary plaque rupture (acute coronary syndrome)
Overall health and presence of other co-morbidities

Clinical Factors

An initial scoring system was proposed by the Framingham Heart Study group to predict 10 year risk for patients with CAD based upon:

Patient’s age and sex
Total cholesterol
Presence of hypertension
History of smoking and diabetes
Presence of other peripheral vascular diseases

For a full discussion on individual risk stratifying topics, visit the microchapters below:

Exercise testing for Risk Stratification and Prognosis:

Risk Stratification Categories and Appropriate Management

Patients at low risk have an annual mortality rate of less than 1% and can be managed medically.
Patients at intermediate risk have an annual mortality rate of 1%–3% and may require additional imaging studies such as exercise imaging for further risk assessment.
Patients at high risk have an annual mortality rate of more than 3% and require coronary angiography.

Risk Stratification of Chronic Stable Angina in Symptomatic Patients

The next step after establishing the clinical probability of angina is to assess the risk of underlying coronary artery disease based on initial rest ECG and the patients ability to exercise.

If the rest ECG is abnormal, the next step is to conduct a stress imaging test.
If the patient is unable to exercise then a pharmacological stress test is used to stratify the risk underlying the atherosclerotic state.
For patients with CCS class III or IV angina, patients with poor LVEF or non responsive to medical therapy there may be some benefit to performing coronary angiography.

ACC/AATS/AHA/ASE/ASNC/SCAI/SCCT/ STS 2017 Appropriate Use Criteria for Coronary Revascularization in Patients With Stable Ischemic Heart Disease

Noninvasive Risk Stratification
High risk (>3% annual death or MI) 1. Severe resting LV dysfunction (LVEF <35%) not readily explained by noncoronary causes 2. Resting perfusion abnormalities ≥10% of the myocardium in patients without prior history or evidence of MI 3. Stress ECG findings including ≥2 mm of ST-segment depression at low workload or persisting into recovery, exercise-induced ST-segment elevation, or exercise-induced VT/VF 4. Severe stress-induced LV dysfunction (peak exercise LVEF <45% or drop in LVEF with stress ≥10%) 5. Stress-induced perfusion abnormalities encumbering ≥10% myocardium or stress segmental scores indicating multiple vascular territories with abnormalities 6. Stress-induced LV dilation 7. Inducible wall motion abnormality (involving >2 segments or 2 coronary beds) 8. Wall motion abnormality developing at low dose of dobutamine (≤ 10 mg/kg/min) or at a low heart rate (<120 beats/min) 9. CAC score >400 Agatston units 10. Multivessel obstructive CAD (≥70% stenosis) or left main stenosis (≥50% stenosis) on CCTA
Intermediate risk (1% to 3% annual death or MI) 1. Mild/moderate resting LV dysfunction (LVEF 35% to 49%) not readily explained by noncoronary causes 2. Resting perfusion abnormalities in 5% to 9.9% of the myocardium in patients without a history or prior evidence of MI 3. ≥1 mm of ST-segment depression occurring with exertional symptoms 4. Stress-induced perfusion abnormalities encumbering 5% to 9.9% of the myocardium or stress segmental scores (in multiple segments) indicating 1 vascular territory with abnormalities but without LV dilation 5. Small wall motion abnormality involving 1 to 2 segments and only 1 coronary bed 6. CAC score 100 to 399 Agatston units 7. One vessel CAD with ≥70% stenosis or moderate CAD stenosis (50% to 69% stenosis) in ≥2 arteries on CCTA
Low risk (<1% annual death or MI) 1. Low-risk treadmill score (score ≥5) or no new ST segment changes or exercise-induced chest pain symptoms; when achieving maximal levels of exercise 2. Normal or small myocardial perfusion defect at rest or with stress encumbering <5% of the myocardium* 3. Normal stress or no change of limited resting wall motion abnormalities during stress 4. CAC score <100 Agaston units 5. No coronary stenosis >50% on CCTA
CAC indicates coronary artery calcium; CAD, coronary artery disease; CCTA, coronary computed tomography angiography; LV, left ventricular; LVEF, left ventricular ejection fraction; and MI, myocardial infarction.

Guidelines for Risk Stratification of Chronic Stable Angina

Visit the microchapters below:

References

↑ Daly CA, De Stavola B, Sendon JL, Tavazzi L, Boersma E, Clemens F et al. (2006) Predicting prognosis in stable angina–results from the Euro heart survey of stable angina: prospective observational study. BMJ 332 (7536):262-7. DOI:10.1136/bmj.38695.605440.AE PMID: 16415069

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[pmid16415069-1] Daly CA, De Stavola B, Sendon JL, Tavazzi L, Boersma E, Clemens F et al. (2006) Predicting prognosis in stable angina–results from the Euro heart survey of stable angina: prospective observational study. BMJ 332 (7536):262-7. DOI:10.1136/bmj.38695.605440.AE PMID: 16415069

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