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

María C. Carrero, Consejo de Ecocardiografía y Doppler vascular “Oscar Orías”- Sociedad Argentina de Cardiología, Buenos Aires, Argentina
María G. Matta, Department of Cardiology. Gold Coast University Hospital. Southport, Australia
Iván Constantin, Consejo de Ecocardiografía y Doppler vascular “Oscar Orías”- Sociedad Argentina de Cardiología, Buenos Aires, Argentina
Gerardo Masson, Consejo de Epidemiología - Sociedad Argentina de Cardiología, Buenos Aires, Argentina
Federico M. Asch, MedStar Health Research Institute y Georgetown University, Washington DC, United States of America

Objectives: patient body size and sex are significant factors in determining aortic dimensions. While females generally have smaller aortic dimensions, the criteria for surgical intervention in thoracic aortic aneurysms primarily rely on absolute diameters, disregarding sex-specific differences. The aim of this study was to compare sex differences in the upper limit of normal (ULN) and Z score in the population of a prospective nationwide multicenter registry and to determine the usefulness and fairness of guideline recommendations regarding aortic diameters in females. Materials and methods: Transthoracic echocardiograms were performed on all patients enrolled measuring aortic dimensions at six levels following the current standard recommendations. Absolute diameters and indexed diameters by body surface area (BSA) and height were compared between males and females. Results: A total of 1,000 healthy adults were included, with an average age of 38.3 ± 12.7 years. Among them, 553 were females, and the majority were either Caucasian or Native American. Females exhibited lower values in all anthropometric parameters, echocardiographic measurements, and blood pressure. Analysis of aortic measurements revealed that females had lower absolute aortic diameters across all segments. However, when indexed parameters were examined in the aortic root and Sino tubular Junction, females demonstrated lower height-indexed diameters but higher BSA-indexed diameters. The ULN for females, correlating with a Z-score of 2.5, was determined to be 3.62 cm. Conclusion: Our study demonstrates the need for sex-specific considerations in defining aortic dilation, as females exhibit lower absolute aortic diameters but variations in indexed parameters, highlighting the limitations of using a universal cutoff value.

Keywords: Ascending aorta. Echocardiography. Female. Dimension. Reference values.