Abstract 15041: Aortic Stiffness is Associated With a Reduced Coronary Flow Reserve

IntroductionLarge artery stiffness promotes a steep diastolic pressure decay and an early arrival of wave reflections to the proximal aorta, reducing diastolic pressure augmentation by the reflected wave.MethodsWe assessed the relationship between coronary flow reserve and carotid-femoral pulse wave velocity (CF-PWV) among 101 patients referred for a clinically indicated regadenoson stress cardiac MRI study. We measured CF-PWV using high-fidelity applanation tonometry. Coronary blood flow was assessed semiquantitatively before and after the administration of 5 ml of intravenous regadenoson. Subjects were stratified by tertiles of CF-PWV.ResultsMyocardial perfusion reserve decreased progressively with increasing CF-PWV (ANOVA P=0.0081). MPR was 1.36. 1.22 and 1.08 among subjects with low, intermediate and high PWV, respectively (Figure, left panel). These differences persisted after adjustment for age, sex, race, body mass index, systolic blood pressure, ACE inhibitor or ARB use, long-acting nitrates, hydralazine use and history of diabetes mellitus (ANCOVA P=0.045) (Figure, right panel).ConclusionsConsistent with its important hemodynamic effect on coronary perfusion pressure, our study demonstrated that increased large artery stiffness is associated with a reduced myocardial perfusion reserve.