24 January 2020
To assess contemporary pre-test probability estimates for obstructive coronary artery disease in patients with stable chest pain.
In this substudy of a multicentre randomized controlled trial, we compared 2019 European Society of Cardiology (ESC)-endorsed pre-test probabilities with observed prevalence of obstructive coronary artery disease on computed tomography coronary angiography (CTCA). We assessed associations between pre-test probability, 5-year coronary heart disease death or non-fatal myocardial infarction and study intervention (standard care vs. CTCA). The study population consisted of 3755 patients (30–75 years, 46% women) with a median pre-test probability of 11% of whom 1622 (43%) had a pre-test probability of >15%. In those who underwent CTCA ( n = 1613), the prevalence of obstructive disease was 22%. When divided into deciles of pre-test probability, the observed disease prevalence was similar but higher than the corresponding median pre-test probability [median difference 2.3 (1.3–5.6)%]. There were more clinical events in patients with a pre-test probability >15% compared to those at 5–15% and <5% (4.1%, 1.5%, and 1.4%, respectively, P < 0.001). Across the total cohort, fewer clinical events occurred in patients who underwent CTCA, with the greatest difference in those with a pre-test probability >15% (2.8% vs. 5.3%, log rank P = 0.01), although this interaction was not statistically significant on multivariable modelling.