Aging influences pulmonary artery flow and stiffness in healthy individuals: non-invasive assessment using cardiac MRI.

AIM

To investigate age-related changes of the pulmonary artery (PA) using cardiac magnetic resonance imaging (cMRI) in healthy subjects.

MATERIALS AND METHODS

A cross-sectional observational study was conducted on apparently healthy subjects who underwent PA velocity-encoded cMRI. cMRI was used to determine PA stiffness parameters such as PA elasticity, relative area change (PA-RAC) and pulse-wave velocity (PA-PWV), and PA flow parameters by subtracting simultaneous forward flow (FF) and backward flow (BF) velocity across the PA cross-section. Data were presented in five age and sex matched groups.

RESULTS

One hundred and fifty subjects (20-70 years, 75 men) met the enrolment criteria. PA elasticity and PA-RAC significantly decreased with age (p<0.001), while PA-PWV, regurgitant volume (V) and backward flow volume (V) increased in the elderly (p<0.001). Linear regression analysis indicated that PA elasticity (r=-0.441, p<0.0001) and PA-RAC (r=-0.484, p<0.0001) were indirectly and negatively associated with advancing age, whereas PA (r=0.331, p<0.0001), PA-PWV (r=0.490, p<0.0001), V (r=0.335, p<0.0001) and V (r=0.349, p<0.0001) were directly associated with age. Multivariate analysis indicated that age was independently associated with V and V, and the addition of PA and PA-PWV marginally increased its predictive capacity.

CONCLUSION

Aging significantly increases cMRI-based PA flow and stiffness parameters. These could become relevant markers of subclinical changes of the PA geometry in healthy subjects.