Arterial stiffness and central aortic blood pressure in patients with hypertension and abdominal aortic aneurysm

Abstract

Objective. To assess the arterial stiffness, peripheral and central aortic blood pressure (PBP and CBP), and to determinate their relationships with indicators of structural changes of the affected aorta in patients with hypertension (HTN) and abdominal aortic aneurysms (AAA).Design and methods. We examined 75 patients with HTN and AAA and 75 controls with HTN without AAA. Groups matched by age and gender. A PBP was measured by OMRON (Japan). Noninvasive measurements of CBP, augmentation index (AIx), augmentation pressure (AP), carotid-femoral pulse wave velocity (cfPWV) were assessed by SphygmoCor (AtCorMedical, Australia).Results. There was no difference in cfPWV between patients with AAA and control group (10,3 (2,2) vs 9,7 (2,1) m/s; р = 0,102). Age, systolic PBP, and aortic diameter were independent predictors of cfPVV in patients with AAA (β = 0,271, р = 0,029; β = 0,272, р = 0,030 и β = –0,361, р = 0,004, respectively). Patients with large aortic diameter of AAA (> 60 mm) had decreased cfPWV compared with control group (8,8 (1,5) vs 9,7 (2,1) m/s; р < 0,05), patients with AAA diameter less than 60 mm, on the contrary, had increased cfPVV compared with the controls (11,8 (1,7) vs 9,7 (2,1) m/s; р < 0,001). Patients with AAA and patients of control group did not differ in systolic and pulse PBP (138,6 (16,4) vs 138,1 (13,6) mm Hg; р = 0,831 and 58,6 (11,8) vs 59,6 (10,2) mm Hg; р = 0,569, respectively). AIx and AP were higher in patients with AAA versus patients without AAA (27,6 (8,2) vs 21,3 (7,9)%; р < 0,001 and 17,3 (6,8) vs 13,9 (5,4) mm Hg; р = 0,001, respectively). Systolic and pulse CBP were higher in patients with AAA than in patients of control group (130,0 (16,4) vs 124,9 (13,9) mm Hg; р = 0,046 and 49,5 (11,7) vs 45,7 (9,9) mm Hg; р = 0,031, respectively).Conclusions. In patients with AAA cfPWV decreased with the expansion of the maximum aortic diameter. CfPWV is not suitable for accurate arterial stiffness assessment in patients with HTN and AAA due to the apparent confounding effect of aneurysm on the biomechanical properties of the aorta. Local assessment of the elastic properties of the aorta such as computed tomography angiography and magnetic resonance imaging is required for arterial stiffness evaluation in patients with AAA. Parameters of the reflected pulse wave such as AP and AIx are increased in patients with AAA. This might contribute to the increase in central aortic BP and target organ damage in patients with HTN combined with AAA.