Author + information
- Received October 7, 2011
- Accepted October 17, 2011
- Published online April 1, 2012.
- Alistair C. Lindsay, MBChB, DPhil⁎,
- Luca Biasiolli, MSc⁎,
- Justin M.S. Lee, MA⁎,
- Ilias Kylintireas, MD, DPhil⁎,
- Bradley J. MacIntosh, PhD†,
- Hilary Watt, MA, MSc‡,
- Peter Jezzard, PhD†,
- Matthew D. Robson, PhD⁎,
- Stefan Neubauer, MD⁎,
- Ashok Handa, MD§,
- James Kennedy, MD∥ and
- Robin P. Choudhury, MA, DM⁎,⁎ ()
- ↵⁎Reprint requests and correspondence to:
Dr. Robin Choudhury, Department of Cardiovascular Medicine, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom
Objectives The goal of this study was to determine whether a 3-T magnetic resonance imaging (MRI) protocol combining carotid atherosclerotic plaque and brain imaging can identify features of high-risk acutely symptomatic plaque that correlate with brain injury.
Background It has previously been demonstrated that, in asymptomatic patients, MRI can identify features of carotid plaque that are associated with stroke, such as the presence of a large lipid core. We hypothesized that the early phase (<7 days) after a cerebrovascular event, when risk of recurrence is highest, may be associated with particular plaque characteristics that associate with cerebral injury.
Methods Eighty-one patients (41 presenting acutely with transient ischemic attack [TIA] or minor stroke and 40 asymptomatic controls) underwent multicontrast carotid artery MRI on 2 separate occasions, each accompanied by diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) imaging of the brain.
Results Complex (American Heart Association [AHA] type VI) plaques were seen in 22 of 41 patients (54%) in the symptomatic group versus 8 of 40 (20%) in the asymptomatic group (p < 0.05). They were caused by intraplaque hemorrhage (34% vs. 18%; p = 0.08), surface rupture (24% vs. 5%; p = 0.03), or luminal thrombus (7% vs. 0%; p = 0.24). Noticeably, 17 of 30 (57%) cases of AHA type VI plaque were in vessels with <70% stenosis. At follow-up scanning (>6 weeks later), only 2 cases of symptomatic AHA type VI plaque showed evidence of full healing. The presence of fibrous cap rupture was associated with higher DWI brain injury at presentation and higher total cerebral FLAIR signal at follow-up (p < 0.05).
Conclusions Early carotid wall MRI in patients experiencing minor stroke or TIA showed a higher proportion of “complex” plaques compared with asymptomatic controls; a majority were in arteries of <70% stenosis. Fibrous cap rupture was associated with increases in DWI and FLAIR lesions in the brain. Combined carotid plaque and brain MRI may aid risk stratification and treatment selection in acute stroke and TIA.
Dr. Choudhury is a Wellcome Trust Senior Research Fellow in Clinical Science. Dr. Lindsay was a Radcliffe Cardiovascular Research Fellow. This study was supported by the Oxford Comprehensive Biomedical Research Centre, National Institute for Health Research funding scheme. Drs. Neubauer and Choudhury acknowledge the support of the British Heart Foundation Centre of Research Excellence, Oxford. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received October 7, 2011.
- Accepted October 17, 2011.
- American College of Cardiology Foundation