Abstract OBJECTIVES The aim of this study was to determine stroke rates in patients who did or did not undergo routine computed tomography angiography (CTA) aortic imaging before isolated coronary artery bypass grafting (CABG). METHODS We conducted a retrospective analysis of a prospectively maintained single-centre registry. Between 2009 and 2016, a total of 2320 consecutive patients who underwent isolated CABG at our institution were identified. Propensity score matching was used to create a paired cohort of patients with similar baseline characteristics who did (CTA cohort) or did not (non-CTA cohort) undergo preoperative aortic CTA. The primary end point of the analysis was in-hospital stroke. RESULTS In 435 propensity score-matched pairs, stroke occurred in 4 patients (0.92%) in the CTA cohort and in 14 patients (3.22%) in the non-CTA cohort (P = 0.017). Routine preoperative aortic CTA was associated with a significantly reduced risk of in-hospital stroke [relative risk 0.29, 95% confidence interval (CI) 0.09–0.86; P = 0.026; absolute risk reduction 2.3%, 95% CI 0.4–4.2; P = 0.017; number needed to treat = 44, 95% CI 24–242]. CONCLUSIONS A preoperative screening for atheromatous aortic disease using CTA is associated with reduced risk of stroke after CABG. The routine use of preoperative aortic CTA could be applied so that surgical manipulation of the ascending aorta can be selectively reduced or avoided in patients with atheromatous aortic disease.