Estimated Aortic Pulse Wave Velocity Is Associated With Faster Thoracic Aortic Aneurysm Growth: A Prospective Cohort Study With Sex-Specific Analyses.

Abstract

Thoracic aortic aneurysm (TAA) is associated with high morbidity and mortality, and there is a critical need for improved tools for risk assessment and prognostication. We have previously shown that aortic stiffness, measured from arterial tonometry (carotid-femoral pulse wave velocity [cfPWV]), is independently associated with TAA expansion. To increase clinical applicability, we sought to determine the association of mathematically estimated aortic pulse wave velocity (e-PWV) with TAA expansion. One-hundred and five consecutive unoperated subjects with TAA were recruited. We used arterial tonometry to measure cfPWV and used mean arterial pressure and age to calculate e-PWV according to validated equations. Multivariable linear regression assessed associations of baseline e-PWV with future aneurysm growth. Given sex differences in TAA outcomes, sex-stratified analyses were performed. Seventy-eight percent of subjects were men. Mean ± standard deviation (SD) age, baseline aneurysm size, and follow-up time were 62.6 ± 11.4 years, 46.2 ± 3.8 mm, and 2.9 ± 1.0 years, respectively. Aneurysm growth was 0.43 ± 0.37 mm per year; e-PWV was independently associated with future aneurysm expansion (β ± SE: 0.240 ± 0.085, P= 0.006). In sex-specific analyses, e-PWV was associated with aneurysm growth in both men (β ± standard error (SE) : 0.076 ± 0.022, P= 0.001) and women (β ± SE : 0.145 ± 0.050, P= 0.012), but the strength of association nearly twice as strong in women as in men. Greater aortic stiffness reflects worse aortic health and provides novel insights into disease activity; e-PWV is independently associated with TAA growth. This finding increases clinical applicability, as e-PWV can be estimated simply, quickly, and free of cost without the need for specialized equipment.