Heuts S, Adriaans BP, Rylski B, et al. - As regular diameter follow-up is required in the management of thoracic aortic aneurysms (TAAs) until the indication criterion for prophylactic surgery is reached, researchers investigated the diagnostic accuracy of ascending aortic diameter, length and volume for occurrence of acute type A aortic dissections (ATAADs) in this two-centre observational cohort study. They performed retrospective screening of 477 consecutive patients who presented with ATAAD between 2009 and 2018. Twenty five of these patients (5.2%) underwent CT angiography (CTA) within 2 years before dissection onset. Comparison of aortic diameter, length and volume of these patients (‘pre-ATAAD’) with those of TAA controls (n = 75) was done. The surgical diameter threshold of 55 mm was not met in 96% of patients with pre-ATAAD before dissection onset.  Patients with pre-ATAAD vs TAA controls exhibited comparable maximal aortic diameters and volume but had significantly larger ascending aortic length. The analysis revealed superior diagnostic accuracy of measurements of aortic volume and length vs the maximal diameter and hence these could improve the timely recognition of patients at risk for ATAAD.