Site-specific association between distal aortic pulse wave velocity and peripheral arterial stenosis severity: a prospective cardiovascular magnetic resonance study

van den Bosch et al. Journal of Cardiovascular Magnetic Resonance (2015) 17:2 DOI 10.1186/s12968-014-0095-8 RESEARCH Open Access Site-specific association between distal aortic pulse wave velocity and peripheral arterial stenosis severity: a prospective cardiovascular magnetic resonance study Harrie C M van den Bosch1*, Jos J M Westenberg2, Wikke Setz-Pels1, John Wondergem1, Ron Wolterbeek3, Lucien E M Duijm4, Joep A W Teijink5 and Albert de Roos2 Abstract Background: Vascular disease expression in one location may not be representative for disease severity in other vascular territories, however, strong correlation between disease expression and severity within the same vascular segment may be expected. Therefore, we hypothesized that aortic stiffening is more strongly associated with disease expression in a vascular territory directly linked to that aortic segment rather than in a more remote segment. We prospectively compared the association between aortic wall stiffness, expressed by pulse wave velocity (PWV), sampled in the distal aorta, with the severity of peripheral arterial occlusive disease (PAOD) as compared to atherosclerotic markers sampled in remote vascular territories such as PWV in the proximal aorta and the normalized wall index (NWI), representing the vessel wall thickness, of the left common carotid artery. Methods: Forty-two patients (23 men; mean age 64±10 years) underwent velocity-encoded cardiovascular magnetic resonance (CMR) in the proximal and distal aorta, whole-body contrast-enhanced MR angiography (CE-MRA) and carotid vessel wall imaging with black-blood CMR in the work-up for PAOD. Strength of associations between aortic stiffness, carotid NWI and peripheral vascular stenosis grade were assessed and evaluated with multiple linear regression. Results: Stenosis severity correlated well with PWV in the distal aorta (Pearson rP=0.64, p<0.001, Spearman rS=0.65, p<0.001) but to a lesser extent with PWV in the proximal aorta (rP=0.48, p=0.002, rS=0.22, p=0.18). Carotid NWI was not associated with peripheral stenosis severity (rP=0.17, p=0.28, rS=0.14, p=0.37) nor with PWV in the proximal aorta (rP=0.22, p=0.17) nor in the distal aorta (rP=0.21, p=0.18). Correlation between stenosis severity and distal aortic PWV remained statistically significant after correction for age and gender. Conclusions: Distal aortic wall stiffness is more directly related to peripheral arterial stenosis severity than markers from more remote vascular territories such as proximal aortic wall stiffness or carotid arterial wall thickness. Site-specific evaluation of vascular disease may be required for full vascular risk estimation. Keywords: Cardiovascular magnetic resonance, Atherosclerosis, Peripheral arterial occlusive disease, Pulse wave velocity, Carotid vessel wall * Correspondence: 1 Department of Radiology, Catharina Hospital, Michelangelolaan 2, 5623EJ, Eindhoven, The Netherlands Full list of author information is available at the end of the article © 2015 van den Bosch et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. van den Bosch et al. Journal of Cardiovascular Magnetic Resonance (2015) 17:2 Background It is well known that the expression of vascular disease in one location may not be representative for the severity of disease in other vascular territories. From an observational cardiovascular magnetic resonance (CMR) study in 394 subjects, Barbier et al. reported that unrecognized myocardial infarction was not associated with manifestation of atherosclerosis depicted on whole-body MR angiography, nor with increased intima-media thickness (IMT) sampled in the carotid artery [1]. However, strong correlation has been reported between vascular disease expression and vascular wall changes within the same vascular segment. Increased wall thickness and wall stiffening in the carotid artery have been associated with the presence of atherosclerotic plaque in patients with hypertension and elderly patients [2]. Additionally, a stronger association between arterial vessel wall thickness and wall stiffness has been demonstrated when these markers were sampled regionally within the same vascular territory of either the aorta or the carotid artery, rather than across vascular territories [3]. Atherosclerosis involves both arterial wall thickening due to fatty degeneration (i.e., atherosis) and arterial wall stiffening due to media degeneration (i.e., sclerosis) [4,5]. Atherosclerosis is therefore not limited to luminal narrowing and structural changes in the arterial wall, but is also strongly associated with arterial wall stiffening [6]. The pulse wave velocity (PWV) has been acknowledged as an important indicator for increased aortic stiffness with prognostic value for cardiovascular events [7,8]. With velocityencoded CMR, the PWV can be accurately assessed with high reproducibility, regionally in the aorta [9]. We hypothesized that aortic stiffening is more strongly associated with the expression of vascular disease in the vascular territory at risk directly linked to that aortic segment rather than in a more remote aortic segment or in other vascular territories. Accordingly, the purpose of this study was to prospectively compare the association between aortic wall stiffness, expressed by pulse wave velocity, sampled in the distal aorta with the severity of peripheral arterial occlusive disease as compared to atherosclerotic markers sampled in remote vascular territories such as PWV in the proximal aorta and normalized wall index [10] describing the vessel wall thickness of the left common carotid artery. Methods Patients In our study, 42 consecutive patients (23 men; mean age 64±10 years) were included who were clinically referred for CE-MRA evaluation and were either suspected for PAOD due to clinical symptoms or already known to be suffering from PAOD and had to undergo follow-up evaluation. In all patients, a single comprehensive CMR Page 2 of 9 examination was performed consisting of a moving-table CE-MRA of the run-off vessels, carotid vessel wall imaging and assessment of the aortic pulse wave velocity. In all patients, the glomerular filtration rate (GFR) was >60 mL/min/1.73 m2. No adverse reactions or complications occurred during or after MRA. Institutional Review Board approval and written informed consent was obtained from all patients. Of note, 16 patients of the present study have been described previously in a study comparing different MRA techniques of the run-off vessels [11]. CMR protocol CMR was perform (...truncated)