DOI:10.2214/AJR.05.2070
AJR 2006; 187:W241
© American Roentgen Ray Society
Regression of Coronary Atherosclerotic Plaque as Shown by CT Arteriography
Kevin M. Johnson,
David A. Dowe,
Tara M. Catanzano and
James A. Brink
Yale University School of Medicine New Haven, CT 06510
Atlantic Medical Imaging Galloway, NJ 08205
Yale University School of Medicine New Haven, CT 06510
Atherosclerosis is not a static process. A slow build up of plaque over
time is the usual course, but instances of regression have also been seen
[1]. These are of great
interest because they may hold clues to controlling or even reversing the
disease. Although plaque in the carotids, aorta, and peripheral arteries can
be imaged noninvasively by several techniques, the coronary arteries have been
more difficult because of their motion. Noninvasive imaging of coronary artery
plaque has until recently been restricted to calcified areas. Advances in CT
arteriography now enable imaging of noncalcified plaque as well
[2].
A 53-year-old asymptomatic man presented with a family history of coronary
atherosclerosis. His was on atorvastatin therapy, 10 mg daily, and his total
serum cholesterol was 190 mg/dL. He was not hypertensive, diabetic, or a
smoker. Because of his desire to better characterize his risk, he requested
coronary arteriography using CT.
Imaging was performed on a 16-MDCT scanner (LightSpeed 16, GE Healthcare).
Curved reformatted images of the coronary arteries were made on a GE
Healthcare Advantage Workstation with dedicated software. Views of the plaque
were matched for position and orientation and traced by hand (ImageJ, National
Institutes of Health).
The patient's first CT scan showed plaque in the left anterior descending
coronary artery 13.5 mm in length; the greatest longitudinal area was 20
mm2 and the transverse area was 5 mm2
(Fig. 9). Part of the central
area had attenuation matching the enhanced arterial lumen (220 H) and
represented either volume averaging with calcium or possibly an ulceration.
Another part had calcium attenuation (403 H). The shoulders on either side of
this had attenuation values between 80 H and 100 H.
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Fig. 9 —Thin-section maximum-intensity-projection images of left main
and anterior descending coronary arteries from three noninvasive CT
arteriograms show regression of plaque over 26 months during atorvastatin
therapy. Images show one perspective; data sets are 3D. Observations were
confirmed in multiple planes. ao = aorta and lm = left main, lcx = circumflex,
sp1 = first septal perforator, d1 = first diagonal, d2 = second diagonal
coronary arteries.
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The patient increased his atorvastatin to 40 mg daily. After 14 months of
clinical followup, he requested a repeat scan, which showed that the plaque
size had decreased to 13 mm in length with longitudinal area of 13.5
mm2 and transverse area of 4.5 mm2
(Fig. 9). The central area now
had a larger area of calcium attenuation (413 H). At 26 months, the patient
developed new atypical chest discomfort and was scanned a third time. The
plaque center appeared more densely calcified (606 H) than before, and the
plaque size had further decreased to 13 mm in length, longitudinal area, 11
mm2; and transverse area, 5.5 mm2
(Fig. 9).
CT coronary arteriography can, in some cases, show the evolution of
atherosclerotic plaque over time
[3]. CT may become a useful
research tool to study the natural history of plaque, the relationship between
plaque burden and risk factors, and the effects of pharmacologic intervention
on plaque size and composition
[4]. A robust automated or
semiautomated segmentation algorithm will be needed to measure plaque volumes
quickly and accurately if CT is to be used to stratify risk and to follow
therapy. Reproducibility of the measurements will be especially important.
References
- Jensen LO, Thayssen P, Pedersen KE, et al. Regression of coronary
atherosclerosis by simvastatin: a serial intravascular ultrasound study.
Circulation 2004;110
: 265-270[Abstract/Free Full Text]
- Achenbach S, Moselewski F, Ropers D, et al. Detection of calcified
and noncalcified coronary atherosclerotic plaque by contrast-enhanced,
submillimeter multidetector spiral computed tomography: a segment-based
comparison with intravascular ultrasound. Circulation2004; 109:14
-17[Abstract/Free Full Text]
- Sato Y, Inoue F, Yoshimura A, et al. Regression of an
atherosclerotic coronary artery plaque demonstrated by multislice spiral
computed tomography in a patient with stable angina pectoris. Heart
Vessels 2003; 18:224
-226[CrossRef][Medline]
- Taylor A, Shaw LJ, Fayad Z, et al. Tracking atherosclerosis
regression: a clinical tool in preventive cardiology.
Atherosclerosis 2005;180
: 1-10[CrossRef][Medline]
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