Patient selection and data collection
This study was performed at a single institution. There was no specific funding provided for this study. This study was exempt from Institutional Review Board approval under Category (4): Secondary research for which consent is not required. We retrospectively compared two groups of patients who had computed tomography angiograms (CTA) of their thoracic aorta performed either at UMMC or a referral center prior to transfer to UMMC. We first identified 71 patients treated for ATAAD at UMMC between November 2015 and February 2020 who had thin-slice (<2mm) electrocardiogram-gated CTAs of the thoracic aorta available. To identify controls, we queried our imaging database for thin-slice ECG-gated CTA of the thoracic aorta conducted for reasons other than aortic pathology (such as evaluation of suspected pulmonary embolism). Potential controls were identified (n =205). Propensity score matching was conducted to determine the final study sample. The propensity score was calculated with a logistic model including age, sex, race, body surface area (at time of imaging), and hypertension and matched using a caliper of 0.5 and exact matching on sex, race, and hypertension. Body surface area was calculated using the Mosteller Formula. After matching, 67 patients remained in each group with balance on the factors in the model (Table 1).