A 79-year-old female presents to the low-risk chest pain clinic with intermittent substernal chest pains. The pain typically comes on with exertion and improves with rest. A trial of GTN has been given by her GP which helps with her pain. She is a known ex-smoker of 30 pack-years. She has no diabetes, hyperlipidaemia, hypertension, and no family history of coronary artery disease.
On examination her observations are stable. On auscultations of her chest, her first and second heart sounds are audible with no added sounds and her lungs are clear.
A pre-test probability is calculated for coronary artery disease which gives a result of 45%.
What is the most important investigation to pursue given her risk for coronary artery disease?
CT calcium scoring
Coronary angiogram
Stress test ECG
Myocardial perfusion scintigraphy
No further investigations