Exercise Tolerance Tests: Further Notes

Key points

• Per NICE CG95 (updated 2016), ETT is NOT recommended to diagnose or exclude stable angina without known CAD — CT coronary angiography is first-line. ETT retains a role in exercise-capacity assessment and risk stratification (post-MI, hypertrophic cardiomyopathy).
• ETT has a sensitivity of ~80% and specificity of ~70% for ischaemic heart disease.
• Maximum predicted heart rate = 220 - age; aim for at least 85% of maximum predicted for an adequate test.
• Contraindications: MI under 7 days ago, unstable angina, uncontrolled hypertension (systolic over 180) or hypotension (systolic under 90), severe aortic stenosis, LBBB.
• Stop for: exhaustion/request, severe chest pain, ST depression over 3 mm or ST elevation over 2 mm, SBP over 230, SBP falling over 20 mmHg, max predicted HR reached, HR falling over 20%, or arrhythmia. Above-average exercise capacity is a strong predictor of good prognosis post-MI.