Early dynamic changes in haematoma thickness in medically managed type a intramural haematoma: a multicentre retrospective study

OBJECTIVES: This study aimed to investigate changes in haematoma thickness (HT) and the maximum ascending aortic diameter (MAD) early after onset and their association with in-hospital disease progression in type A intramural haematoma (IMH). METHODS: Medical records and serial computed tomography angiography (CTA) scans of 140 patients treated from April 2011 to June 2023 at six hospitals in Japan were retrospectively analysed. Remodelling rates (mm/h) for HT and MAD were calculated using the first two CTAs divided by the scan-interval time. Disease progression during hospitalisation was defined as new ulcer-like projections, haematoma enlargement, false lumen aortic recanalisation of the ascending aorta, or aortic rupture. Associations within these parameters and in-hospital disease progression were evaluated. RESULTS: The mean MAD was 44.2 ± 4.9 mm, and HT was 8.1 ± 4.1 mm. In-hospital disease progression occurred in 35/140 patients (25%), and overall in-hospital mortality was 12/140 (9%). Aortic remodelling was analysed in 129/140 patients. Both HT and MAD demonstrated rapid early negative remodelling and were significantly associated with time from onset, whereas maximum values of HT and MAD within 24 h indicated no significant correlation with time from onset. Logistic regression revealed that HT and its remodelling rate did not predict in-hospital disease progression; only the MAD remodelling rate was an independent predictor (OR 0.71 per 0.1 mm/h, 95% confidence interval 0.52-0.94; p = 0.025). CONCLUSIONS: HT may have limited utility as a single-time-point imaging marker for early risk stratification, and repeated early morphological assessment may be useful in selected medically managed patients with type A IMH.