• Coronary Angiography
• Risk Factors
• Coronary Artery Disease

Precision medicine implies that diagnostic pathways and medical treatment can be targeted towards those who gain meaningful benefit from an intervention. By placing greater emphasis on individualised care, the ultimate goal is that clinical outcomes will continue to improve for future generations of patients, at lower costs of healthcare expenditure and with fewer unwanted side effects. In the outpatient cardiology clinic, a feasible strategy to achieve this precision medicine goal is to defer unnecessary diagnostic testing for patients at very low risk of cardiovascular events. European Society of Cardiology (ESC) guidelines recommend deferring testing in those with <15% pretest probability of obstructive coronary artery, as this cohort has a very low annual risk of cardiovascular disease or myocardial infarction at <1%. Based on the pooled analysis of contemporary data in 15 815 symptomatic patients, deferred testing should be considered for all men <40 years old and for all women <60 years old, unless there are significant risk modifiers.1 Supportive evidence comes from a retrospective subanalysis of the Scottish Computed Tomography of the HEART (SCOT-HEART) trial, of whom 51.4% had an ESC pretest probability of <15%, where the annual risk of myocardial infarction was well below the threshold of <1% (annual risk of cardiovascular death and myocardial infarction 0.3% per annum), and there was no meaningful benefit in cardiovascular outcomes from using coronary CT angiography to guide treatment.2 Yet, this guidance does a disservice to the cohort of younger and female patients who are referred to cardiologists for the investigation of suspected symptomatic coronary artery disease. This raises the pertinent question: do cardiologists have the confidence to adopt a ‘no-test’ strategy when referred a patient who is estimated to be at very low risk of …