Longitudinal analysis of thoracic aortic expansion in non-syndromic real-world patients

Remodeling of the thoracic aorta is commonly seen and viewed as a precursor to an aortic aneurysm. However, while aneurysms have been shown to expand at a rate of approximately 1 mm annually, the expansion of the pre-aneurysmal aorta is poorly characterized, especially in relation to age, gender, and aortic size per se. We identified patients that had undergone echocardiography at least twice at a large university medical center. Diagnosis codes, medications, and blood test results were obtained from hospital records. Syndromic patients were excluded (e.g., Marfan's syndrome, bicuspid aortic valve). Final population comprised n = 24,928 patients (median age 61.2 years (inter-quartile range (IQR): 50.6–71.5); 55.8% males) that had undergone a median of 3 echocardiograms (2–4; range 2–27) during a median of 4.0 years (IQR: 2.3–6.2). Hypertension was present in 39.6% of patients and diabetes in 20.7%, median LV ejection fraction was 56.0% (IQR: 41.0–62.0). Aortic size measurements were analyzed in mixed models while clustering on individual patients. Mean expansion was determined for sinus of Valsalva as 1.93 (95% confidence interval; CI(95): 1.87–1.99) mm per decade, and for ascending aorta as 1.76 (CI(95): 1.70–1.82) mm per decade. Faster expansion was found in males, with larger aortic size, and younger age (p for interaction <0.05 for all). In conclusion, expansion of the thoracic aorta, in real world, non-syndromic patients, is slow and averages <2 mm per decade. This will help to inform management of this large patient group.