CLINICAL RESEARCH: CARDIAC IMAGING
Prevalence of American Heart Association Type VI Carotid Atherosclerotic Lesions Identified by Magnetic Resonance Imaging for Different Levels of Stenosis as Measured by Duplex Ultrasound
Tobias Saam, MD*, ,
Hunter R. Underhill, MD,
Baocheng Chu, MD, PhD,
Norihide Takaya, MD, PhD,
Jianming Cai, MD, PhD,
Nayak L. Polissar, PhD ,
Chun Yuan, PhD and
Thomas S. Hatsukami, MD ,*
* Department of Clinical Radiology, University of Munich, Grosshadern Campus, Munich, Germany
Department of Radiology, University of Washington, Seattle, Washington
The Mountain-Whisper-Light Statistical Consulting, Seattle, Washington
VA Puget Sound Health Care System and Department of Surgery, University of Washington, Seattle, Washington.
Manuscript received July 5, 2007;
revised manuscript received August 30, 2007,
accepted October 15, 2007.
* Reprint requests and correspondence: Dr. Thomas S. Hatsukami, VA Puget Sound Health Care System, Surgery and Perioperative Care (112), 1660 South Columbian Way, Seattle, Washington 98108. (Email: tomhat{at}u.washington.edu).
Objectives: Via magnetic resonance imaging (MRI), we sought to determine the prevalence of atherosclerotic American Heart Association type VI lesions (AHA-LT6) (lesions with luminal surface defect, hemorrhage/thrombus, or calcified nodule) in carotid arteries that represented all categories of stenosis as measured by duplex ultrasound.
Background: Arterial stenosis alone has been shown to be a poor predictor of cardiovascular events. Autopsy studies suggest that features associated with AHA-LT6 lesions, rather than the degree of luminal narrowing, characterize the high-risk plaque.
Methods: A total of 192 subjects underwent bilateral carotid artery magnetic resonance imaging (MRI) scans at 1.5T after evaluation with ultrasound to determine stenosis. After excluding arteries with a previous endarterectomy, poor image quality, or missing ultrasound data, there were 175 patients with 260 arteries available for analysis. The AHA lesion type was determined by the consensus opinion of 2 experienced carotid MRI reviewers.
Results: In total, 96 of 260 (37.0%) arteries had  1 location with AHA-LT6. Of the arteries with AHA-LT6, 84.4% had hemorrhage, 45.8% had a ruptured fibrous cap, and 14.6% showed other type of complications. Prevalence of AHA-LT6 was an increasing sequence of 8.1% in the 37 arteries with 1% to 15% stenosis, 21.7% in the 60 arteries with 16% to 49% stenosis, 36.8% in the 114 arteries with 50% to 79% stenosis, and 77.6% in the 49 arteries with 80% to 99% stenosis.
Conclusions: Complicated AHA-LT6 are frequently found in arteries with  50% stenosis. These findings indicate that complex lesions develop in a substantial number of arteries in the absence of high-grade stenosis. Ongoing prospective studies will determine the predictive value of vulnerable plaque features, as visualized by MRI, for risk of subsequent ischemic events.
|
Abbreviations and Acronyms
| | 3D = 3-dimensional | | AHA = American Heart Association | | ImQ = image quality | | LT = lesion type | | MRI = magnetic resonance imaging | | NWI = normalized wall index | | PD = proton-density | | TOF = time-of-flight |
|
This article has been cited by other articles:
|
|
|
|
 
J E van Velzen, J D Schuijf, F R de Graaf, G Nucifora, G Pundziute, J W Jukema, M J Schalij, L J Kroft, A de Roos, J H C Reiber, et al.
Plaque type and composition as evaluated non-invasively by MSCT angiography and invasively by VH IVUS in relation to the degree of stenosis
Heart,
December 15, 2009;
95(24):
1990 - 1996.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. J. Daemen and M. E. Kooi
Intraplaque Hemorrhage as a Stimulator of Episodic Growth of Advanced, But Nonsymptomatic Atherosclerotic Lesions: Bridging the Gap
J. Am. Coll. Cardiol. Img.,
December 1, 2009;
2(12):
1390 - 1392.
[Full Text]
[PDF]
|
|
|
|
|
|
|
C. M. Matter, M. Stuber, and M. Nahrendorf
Imaging of the unstable plaque: how far have we got?
Eur. Heart J.,
November 1, 2009;
30(21):
2566 - 2574.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
H. Ota, W. Yu, H. R. Underhill, M. Oikawa, L. Dong, X. Zhao, N. L. Polissar, B. Neradilek, T. Gao, Z. Zhang, et al.
Hemorrhage and Large Lipid-Rich Necrotic Cores Are Independently Associated With Thin or Ruptured Fibrous Caps: An In vivo 3T MRI Study
Arterioscler Thromb Vasc Biol,
October 1, 2009;
29(10):
1696 - 1701.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
D. Li, Z. A. Fayad, and D. A. Bluemke
Can contrast-enhanced cardiac magnetic resonance assess inflammation of the coronary wall?
J. Am. Coll. Cardiol. Img.,
May 1, 2009;
2(5):
589 - 591.
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. Sanz, P. R. Moreno, and V. Fuster
The Year in Atherothrombosis
J. Am. Coll. Cardiol.,
April 14, 2009;
53(15):
1326 - 1337.
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. N. DeMaria, O. Ben-Yehuda, J. J. Bax, G. K. Feld, B. H. Greenberg, W. Y.W. Lew, J. A.C. Lima, A. S. Maisel, S. M. Narayan, D. J. Sahn, et al.
Highlights of the Year in JACC 2008.
J. Am. Coll. Cardiol.,
January 27, 2009;
53(4):
373 - 398.
[Full Text]
[PDF]
|
|
|
|
