Aortic enlargement in two weeks is associated with subsequent aortic events in patients with type B acute aortic syndrome

Objectives: To determine whether aortic enlargement in 2 weeks in patients with type B acute aortic syndrome is associated with aorta-related adverse events.

Methods: This retrospective, single-center study included 183 patients who were diagnosed with uncomplicated type B acute aortic syndrome (classic aortic dissection and intramural hematoma) between 2010 and 2019 and had follow-up computed tomography at second or third week. Aortic diameter was measured at admission and at predischarge follow-up. Aorta-related adverse events were defined by a composite of aortic rupture, surgical or endovascular aortic repair, redissection, severe intestinal malperfusion, and aortic enlargement.

Results: The patients whose aortic diameter enlarged ≥2 mm but <5 mm in 2 weeks were categorized as moderate aortic enlargement group. During follow-up, 51 patients (28%) had aorta-related adverse events and 36 patients (20%) had moderate aortic enlargement. Patients with moderate aortic enlargement showed lower aorta-related event-free survival rates than those without moderate enlargement (48 ± 9% vs 90 ± 3% at 1 year, P < .001). On multivariable analysis, moderate aortic enlargement (subhazard ratio, 3.64; 95% confidence interval, 2.08-6.35; P < .001) and aortic diameter ≥40 mm at admission (subhazard ratio, 2.96; 95% confidence interval, 1.60-5.48; P < .001) were associated with aorta-related adverse events.

Conclusions: Moderate aortic enlargement in 2 weeks is a significant risk factor of aorta-related adverse events in patients with uncomplicated type B acute aortic syndrome. Patients with moderate aortic enlargement should be followed up carefully and may be candidates for subsequent endovascular treatment.