Measures of carotid-femoral pulse wave velocity and augmentation index are not reliable in patients with abdominal aortic aneurysm

Background: Measures of carotid-femoral pulse wave velocity (cf-PWV) and carotid augmentation index (cAI) may be affected by the presence of an abdominal aortic aneurysm (AAA). We, therefore, investigated series of various measures of arterial stiffness and wave reflections in patients with AAA, before and 4 weeks after endovascular aneurysm repair (EVAR). Methods: A total of 51 patients (75.2 ± 11.6 years, 92.2% men) underwent EVAR for AAA and 51 controls with matched age, sex, SBP, and comorbidity were enrolled. Measures of aortic stiffness included cf-PWV by tonometry and brachial-ankle pulse wave velocity (ba-PWV) by plethysmography. Measures of wave reflections included cAI and the reflected pressure wave amplitude (Pb) from a decomposed carotid pressure wave. Results: Patients with AAA had significantly lower cf-PWV (12.1 ±2.7 versus 13.6±3.5m/s P = 0.009), higher cAI (30.8±12.2 versus 23.1 ±23.3%, P = 0.040) in comparison with controls. After EVAR for AAA, cf-PWV (14.4±3.8ms) increased significantly (P<0.001), and cAI (24.4±14.5%) decreased significantly (P=0.004). In contrast, ba-PWV and Pb values were similar to those in controls and did not change significantly after EVAR. Furthermore, the heart rate and mean BP adjusted post-EVAR cf-PWV, ba-PWV, cAI, and Pb were similar to the corresponding values in controls. Conclusion: In patients with AAA, a lower cf-PWV and a higher cAI are expected, which do not represent true degrees of arterial stiffness and wave reflections. EVAR may correct the impacts of AAA on cf-PWV and cAI.