Impact of renin-angiotensin system targeted therapy on aortic elastic properties assessed by computed tomography

Aortic stiffening is a well-known cardiovascular risk factor. Computed tomography (CT) has proven to be a valuable tool in the assessment of aortic elastic properties. Drugs that inhibit the renin-angiotensin system (RAS) play a central role in cardioprotective therapy. We aimed to evaluate the relationship between aortic elastic properties and RAS-targeted therapy in hypertensive patients.

This is an observational prospective study of hypertensive patients with nonobstructive coronary artery disease who underwent coronary CT angiography (CCTA). Aortic compliance and distensibility were calculated from the ECG-gated CCTA image. Patients were divided into two groups - those with RAS-targeted therapy - RAS(+) and those with non-RAS-targeted therapy - RAS(-). The elastic properties of the aorta were compared between the two groups.

A total of 142 patients were included in the final analysis. 53.5 % of the population were in the RAS(+) group and 46.5 % in the RAS(-) group. Elastic properties of ascending and descending aorta were significantly higher in the RAS(+) group compared to the RAS(-) group: AA compliance 1.42 ± 0.75 mm²/mmHg in the RAS(+) vs 1.03 ± 0.91 mm²/mmHg in the RAS(-), p = 0.024; AA distensibility 2.86 ± 1.11 x10^-3mm³ in the RAS(+) vs 1.82 ± 0.97 x10^-3mm³ in RAS(-), p < 0.001; DA compliance 1.45 ± 1.10 mm²/mmHg in the RAS(+) vs 1.11 ± 0.91 mm²/mmHg in the RAS(-), p 0.031; DA distensibility 2.35 ± 0.84 x10^-3mm³ in the RAS(+) vs 1.73 ± 1.21 x10^-3mm³ in RAS(-), p < 0.001. There was an excellent correlation between RAS therapy and ascending aorta compliance and distensibility (r = 0.901, p < 0.001 and r = 0.875, p < 0.001, respectively).

Patients receiving RAS-blocking treatment revealed significantly higher compliance and distensibility of ascending and descending aorta. In addition, aortic elastic properties were significantly correlated with the RAS-targeted therapy.