Background Takayasu’s arteritis (TA) is a chronic inflammatory vasculitis of the aorta and its major branches. Increased arterial stiffness is known to be a predictor of cardiovascular mortality. Impairment of the elasticity in the involved arteries is an important feature of vascular injury in TA.
Objectives In the present study, we aimed to evaluate aortic and carotid artery elastic properties, to assess carotid arterial mechanics by using a novel strain imaging method, “velocity vector imaging” (VVI), in patients with TA, and to compare them with an inflammatory disorder, systemic lupus erythematosus (SLE).
Methods We studied 31 patients with TA (F/M, 29/2; mean age: 31,4), 18 patients with SLE (F/M, 17/1; mean age: 32,3) and 20 age and sex-matched controls. All the patients and healthy controls were subjected to assessment of aortic strain, stiffness, distensibility and carotid artery stiffness index measurements. Additionally, VVI analysis was performed to determine longitudinal and radial tissue motion of the common carotid arteries (CCA).
Results Aortic strain was significantly impaired in patients with TA, compared to the control group (5.77±3.2% vs 13.91±4.77%, p=0.0001), while aortic stiffness (6.17±5.1 vs 2.6±1.3, p=0.003) and carotid artery stiffness index (4.97±3.3 vs 1.96±0.72, p=0.0001) were markedly increased. We revealed a significant decrease in aortic distensibility in patients with TA, when compared to the healthy volunteers (0.47±0.3 vs 1.64±0.77, p=0.0001). We did not observe marked difference SLE patients and the control group, regarding aortic strain (p=0.43), aortic stiffness (p=0.93), and carotid artery stiffness index (p=0.94) measurements. However, aortic distensibility was also decreased in patients with SLE, compared to controls (0.61±0.3 vs 1.64±0.77, p=0.0001). VVI measurements were obtained from off-line analysis of standard B-mode ultrasound images of the CCA. Peak longitudinal strain and strain rate values and total longitudinal displacement values were significantly impaired in patients with TA, compared to the controls (Strain: 1.22±0.70% vs 4.77±1.26%, p=0.002, Strain rate: 1.17±0.10% vs 0.68±0.32, p=0.0001 and total longitudinal displacement: 0.22±0.10 vs 0.27±0.12, p=0.003). Peak radial velocity was decreased (0.10±0.01 cm/s vs 0.27±0.12 cm/s, p=0.0001), while time to peak radial velocity was markedly increased (221±67.8 ms vs 139±33.8 ms, p=0.0001) in patients with TA. In the SLE group, peak longitudinal strain rate (0.23±0.11, p=0.0001), total longitudinal displacement (0.14±0.01, p=0.04) and peak radial velocity values (0.07±0.02, p=0.0001) were significantly impaired, whereas no marked difference in peak longitudinal strain (p=0.07) and time to peak radial velocity (p=0.09) was obtained.
Conclusions TA and SLE are associated with reduced elasticity of the aorta and the carotid artery system. Longitudinal and radial wall motion of CCA is impaired in patients with TA and SLE, due to the vascular inflamation. VVI is a feasible, novel strain imaging method in assessing the mechanical properties of the arterial system, in patients with chronic vascular inflammation.
Disclosure of Interest None Declared