The Nonsyndromic Ascending Thoracic Aorta in a Population-Based Setting: A 5-Year Prospective Cohort Study.

Summary

In a population-based prospective cohort, nonsyndromic ascending aorta growth was very slow (≈0.07–0.13 mm/year), and AAEs were rare (0.2% over ≈5 years). Diameter increment and family history independently predicted AAE, supporting individualized surveillance intervals beyond diameter alone.

Key Findings

• Mean ascending aorta growth was 0.07 mm/year (men) and 0.13 mm/year (women); growth did not accelerate with larger baseline diameters.
• AAEs were uncommon (0.2% over ≈5 years across 14,962 participants), with most events occurring at diameters <50 mm.
• Each 1-mm increase in diameter (HR 1.24) and family history (HR 5.43) independently increased AAE risk, supporting individualized surveillance.

Clinical Implications

For many nonsyndromic adults, longer imaging intervals may be safe; risk models should incorporate diameter trajectory and family history rather than diameter alone.

Limitations

• Predominantly male cohort limits generalizability to women; larger female cohorts are needed.
• Imaging limited to noncontrast CT; biomechanical factors or genetic modifiers were not assessed.

Future Directions

Develop and validate risk tools combining diameter, growth rate, family history, and clinical factors; test surveillance intervals prospectively, especially in women.