Author + information
- Received June 28, 2010
- Revision received January 5, 2011
- Accepted January 7, 2011
- Published online May 1, 2011.
- Hélène Beaussier, PharmD, PhD⁎,†,
- Olivier Naggara, MD, PhD†,‡,
- David Calvet, MD‡,
- Robinson Joannides, MD, PhD§,
- Evelyne Guegan-Massardier, MD§,
- Emmanuel Gerardin, MD, PhD§,
- Michelle Iacob, MD§,
- Brigitte LaLoux, PhD⁎,†,
- Erwan Bozec, PhD⁎,†,
- Jérémy Bellien, PharmD, PhD§,
- Emmanuel Touze, MD, PhD†,‡,
- Ingrid Masson, PhD⁎∥,
- Christian Thuillez, MD, PhD§,
- Catherine Oppenheim, MD, PhD†,‡,
- Pierre Boutouyrie, MD, PhD⁎,† and
- Stéphane Laurent, MD, PhD⁎,†,⁎ ()
- ↵⁎Reprint requests and correspondence:
Dr. Stéphane Laurent, Department of Pharmacology and INSERM U970, Hôpital Européen Georges Pompidou, Assistance Publique, Hôpitaux de Paris, Université Paris Descartes, 20, rue Leblanc, Paris 75015, France
Objectives The purpose of this study was to correlate the arterial mechanics of carotid atherosclerotic plaques assessed from echotracking with their composition by high-resolution magnetic resonance imaging (HR-MRI).
Background Analysis of the relationship between mechanical parameters and structure of the plaque allows better understanding of the mechanisms leading to mechanical fatigue of plaque material, plaque rupture, and ischemic events. A specific longitudinal gradient of strain (reduced strain, i.e., lower radial strain at the plaque level than at the adjacent segment) has been shown in atherosclerotic plaques on the common carotid artery (CCA) in patients with hypertension, dyslipidemia, or type 2 diabetes mellitus. The structural abnormalities underlying this functional behavior have not been determined.
Methods Forty-six carotid plaques from 27 patients were evaluated; plaques were present at the site of the carotid bifurcation and extended to the CCA. Among the 27 patients, 9 had previous ischemic stroke ipsilateral to carotid stenosis (symptomatic) and 18 had not (asymptomatic). Mechanical parameters were measured at 128 sites on a 4-cm long CCA segment by noninvasive echotracking system, and strain gradient was calculated. Plaque composition was noninvasively determined by HR-MRI.
Results Complex plaques at HR-MRI (i.e., American Heart Association [AHA] stages IV to VIII) more often displayed a reduced strain than the simple plaques (i.e., AHA stages I to III; p = 0.046). HR-MRI verified complex plaques were associated with an outer remodeling upon echotracking, and had a lower distensibility than adjacent CCA (17.0 ± 5.0 MPa−1 vs. 21.7 ± 7.3 MPa−1; p = 0.007). An outer remodeling was observed in plaques with a lipid core at HR-MRI and was more frequent in symptomatic carotids.
Conclusions These findings indicate that the longitudinal mechanics of “complex” plaques follows a specific pattern of reduced strain. They also suggest that reduced strain, associated with an outer remodeling, may be a feature of high-risk plaques.
- arterial remodeling
- atherosclerotic plaque
- carotid artery
- high-resolution magnetic resonance imaging
This study was funded by an unrestricted grant from Astra-Zeneca; by INSERM (PNR 2005; C05-18/DGS 2006/0042), University Paris Descartes, and Assistance Publique-Hôpitaux de Paris; and by Association Charles Nicolle, CHU de Rouen, and Hôpitaux de Rouen. The authors have reported that they have no relationships to disclose.
- Received June 28, 2010.
- Revision received January 5, 2011.
- Accepted January 7, 2011.
- American College of Cardiology Foundation