Association of Pulmonary Vascular Remodeling With Cardiac Structure and Function, Pulmonary Pressure, and Heart...

Aging is associated with increases in pulmonary pressure related to concomitant age-associated left ventricular remodeling, diastolic dysfunction, and declines in pulmonary function. Little is known regarding morphological changes in the pulmonary arterial vasculature underlying these associations. Our aim was to determine the associations between pulmonary vascular arterial remodeling, reflected in distal pruning and proximal dilation, and cardiac structure and function, pulmonary pressure, and functional outcomes.

Among 2275 participants in the community-based Atherosclerosis Risk in Communities study (ARIC) who underwent echocardiography and noncontrast cardiac computed tomography at study visit 7 (2018-2019), we quantified the fraction of total pulmonary vascular area comprised of arterial vessels with cross-sectional area <5 mm² (aBV5/aTBV) and arterial vessels with cross-sectional area >10 mm² (aBVg10/aTBV) using a validated image processing approach. We assessed the associations of aBV5/aTBV and aBVg10/aTBV with echocardiographic measures of cardiac structure and function and pulmonary artery systolic pressure using multivariable linear regression models adjusted for demographics and cardiovascular risk factors. We also evaluated associations of pulmonary vascular arterial remodeling metrics with circulating NT-proBNP (N-terminal pro-B-type natriuretic peptide), self-reported dyspnea, and incident heart failure.

Mean age was 80±4 years, 61% were women, 22% reported Black race, and mean left ventricular ejection fraction was 64±7%. Mean aBV5/aTBV was 0.30±0.08, and aBVg10/aTBV was 0.45±0.09. Lower aBV5/aTBV, reflecting greater distal pruning, and higher aBVg10/aTBV, reflecting greater proximal dilation, were both associated with greater left ventricular remodeling, worse diastolic function, and worse systolic function. Lower aBV5/aTBV and higher aBVg10/aTBV demonstrated nonlinear associations with greater pulmonary artery systolic pressure. Both lower aBV5/aTBV and higher aBVg10/aTBV were associated with higher circulating NT-proBNP and greater odds of moderate to severe dyspnea. Higher aBVg10/aTBV, in particular, was associated with greater risk of incident heart failure over a 4-year follow-up with a hazard ratio of 1.25 (95% CI, 1.03-1.51) per one SD in aBVg10/TBV.

Among older adults, pulmonary vascular arterial remodeling is associated with greater left ventricular remodeling, worse diastolic and systolic dysfunction, greater pulmonary artery systolic pressure, greater odds of significant dyspnea, and greater risk of heart failure development. Our findings clarify the morphologic changes in the pulmonary vasculature that link cardiac dysfunction to higher pulmonary pressure in late life and may appear before symptomatology.