Growth patterns of ascending aortic aneurysms

The increased length and diameter of the ascending aorta are determined as risk factors for acute type A aortic dissection; however, knowledge regarding the growth of these dimensions remains limited. The aim of this study was to explore the growth rates and growth patterns of ascending aortic length and diameter in different patient populations. This study included 117 patients who were either followed up or operated on for ascending thoracic aortic aneurysm or who underwent surgery for acute type A aortic dissection. Patients were divided into two groups based on surgical intervention (follow-up group: n = 87; surgery group: n = 30). Ascending aortic length and diameter were measured using repeated computed tomography or magnetic resonance imaging to assess growth rates and growth patterns. During a mean surveillance period of 6.4 years, the mean growth rate of ascending aortic length was 0.96 ± 0.85 mm/year and that of ascending aortic diameter was 0.53 ± 0.66 mm/year. The surgery group demonstrated higher growth rates for both length (1.42 ± 1.29 mm/year versus 0.82 ± 0.60 mm/year, p = 0.056) and diameter (1.13 ± 0.94 mm/year versus 0.27 ± 0.19 mm/year, p < 0.001). A linear model best described the growth patterns of both dimensions compared to exponential and logarithmic models. The growth rates of the ascending aortic length and diameter were low overall but were higher in patients who required surgery. Both dimensions can be estimated at different time points using a linear model. DilAo-Trial ClinicalTrials.gov ID 5,063,566, Registration date: 14 September 2021.