Single vs. Serial Assessments of Arterial Hemodynamics to Predict Thoracic Aortic Aneurysm (TAA) Expansion.

Abstract

BACKGROUND\nThoracic aortic aneurysm (TAA) is a highly morbid disease. We have previously shown that baseline hemodynamic measures reflecting aortic function (AoFx) are associated with future TAA expansion. However, whether serial arterial hemodynamic assessment further improves TAA growth assessment remains unknown. Thus, we aimed to compare single vs. serial arterial hemodynamic assessments in the evaluation of future TAA growth.\n\n\nMETHODS\nEighty-six unoperated participants with TAA underwent non-invasive arterial hemodynamic assessment using arterial tonometry and echocardiography at baseline and after 1-year. Aortic diameter was measured serially with standard imaging modalities. Stepwise multivariable linear regression was used to assess associations of baseline and 1-year change (Δ) in arterial hemodynamic measures with TAA growth.\n\n\nRESULTS\nMean age was 62.7±11.0 years; 79% were male. Mean±SD aneurysm growth was 0.48±0.54 mm/year after a follow-up of 2.96±1.03 years. Yearly changes in arterial hemodynamic measures ranged from -3.2% to +4.2%. Linear regression results showed that while baseline arterial hemodynamic measures were independently associated with aneurysm growth (carotid-femoral pulse wave velocity: ß±SE\u202f=\u202f0.038±0.013; aortic characteristic impedance: ß±SE=0.002±0.00; proximal aortic compliance: ß±SE= -0.011±0.006; forward pressure wave amplitude: ß±SE 0.009±0.002; reflected pressure wave amplitude: ß±SE= 0.017±0.006. p<0.05 for each), the 1-year Δ in these measures did not incrementally add to aneurysm growth assessment (p>0.05 for each Δ).\n\n\nCONCLUSION\nWhile baseline measures of AoFx independently predict TAA expansion, 1-year changes in these measures do not improve this prediction. Thus, for TAA risk assessment purposes, a baseline assessment of AoFx may suffice, which simplifies its use for potential predictive algorithms.