Assessment of regional aortic stiffness with cardiac magnetic resonance imaging in a healthy Asian population

The aim of this study was to determine the normal values for aortic pulse wave velocity (PWV) and distensibility using cine and phase contrast cardiac magnetic resonance imaging (CMRI) in patients without cardiovascular risk factors. PWV and distensibility are indispensible predictors of global and regional cardiovascular risk. Regional heterogeneity in aortic stiffness plays an important role in the pathogenesis of cardiovascular disease. Contrary to global estimates of aortic PWV that are commonly measured with tonometry, CMRI has emerged as an important method for estimating regional PWV and distensibility. A total of 124 Korean patients, aged 20–79 years and free of cardiovascular risk factors, were categorized by age decade. Using cine and phase contrast sequences, the cross-sectional area for distensibility and average blood flow were measured at four aortic levels: the ascending, upper descending thoracic, lower thoracic and abdominal aorta. Regional PWV was determined in four aortic segments: proximal, descending thoracic, abdominal aorta and across the entire aorta. Distensibility at the four levels of the aorta from the ascending to distal (4.4 ± 2.5, 4.0 ± 1.6, 5.2 ± 1.9, and 3.3 ± 1.7 × 10⁻³ mm/Hg, respectively) was higher in women (P < 0.001) and decreased with age. The regional PWV was highest in the descending thoracic aorta and increased with age. The present study is the first to show the heterogeneity in aortic PWV and distensibility, as well to provide normal values for these parameters using CMRI in an Asian sample.