Sex-specific considerations in defining aortic dilation: findings from the MATEAR study

Area of Science:

• Cardiovascular research
• Medical imaging
• Aortic disease

Background:

• Patient body size and sex significantly influence aortic dimensions.
• Current thoracic aortic aneurysm guidelines use absolute diameters, potentially disadvantaging females who generally have smaller aortas.
• Sex-specific differences in aortic dimensions are not adequately addressed by universal diagnostic criteria.

Purpose of the Study:

• To compare sex differences in the upper limit of normal (ULN) and Z-score for aortic dimensions.
• To evaluate the utility and fairness of current guideline recommendations for aortic diameters in females.
• To establish sex-specific reference values for aortic measurements.

Main Methods:

• Prospective, nationwide, multicenter registry.
• Transthoracic echocardiograms performed on 1,000 healthy adults (553 females).
• Comparison of absolute and indexed (by body surface area and height) aortic diameters between males and females.

Main Results:

• Females exhibited lower anthropometric parameters, echocardiographic measurements, and blood pressure.
• Females had smaller absolute aortic diameters across all measured segments.
• While height-indexed diameters were lower in females, BSA-indexed diameters were higher in the aortic root and Sino-tubular Junction. The ULN for females (Z-score 2.5) was 3.62 cm.

Conclusions:

• Aortic dilation criteria require sex-specific considerations.
• Females display lower absolute aortic diameters but variable indexed parameters, challenging universal cutoff values.
• Current guidelines may not be optimal for diagnosing aortic dilation in females due to a lack of sex-specific thresholds.