Jim Chinnis said:Are there any data linking management of IMT to outcomes?
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Jim Chinnis Warrenton, Virginia, USA
Intima media thickness of the carotid arteries: early pointer to arteriosclerosis and therapeutic
endpoint Ultraschall Med. 2003 Jun;24(3):162-74. tinyurl.com2vc2yOpen ↗ In conclusion, high-
resolution Duplex-sonography seems promising for the detection, quantification and serial
investigations of structural alterations of the arterial wall. The method is sensitive enough to be
applied in clinical studies of the progression and regression of early preintrusive atherosclerotic
lesions in extracranial carotid arteries. Moreover IMT of the common carotid artery can be used as a
therapeutic endpoint.
*CIMT actually simplifies some very complex issues and can be used as a reference as to efficacy of
treatment for complex multiple risk factor interventions while avoiding undertreatment,
overtreatment or unnecessary treatment- pb*
Intima-media thickness: a new tool for diagnosis and treatment of cardiovascular risk. J Hypertens.
2002 Feb;20(2):159-69. tinyurl.com2sw2gOpen ↗ Close relationships have been shown between: (i)
most traditional cardiovascular risk factors; (ii) certain emerging risk factors such as
lipoproteins, psychosocial status, plasma viscosity, or hyperhomocysteinemia; and (iii) various
cardiovascular or organ damages such as white matter lesion of the brain, left ventricular
hypertrophy, microalbuminuria or decreased ankle to brachial systolic pressure index. Thus, IMT
gives a comprehensive picture of the alterations caused by multiple risk factors over time on
arterial walls.
*If an individual is showing progression of CIMT over time, it may indicate a "hidden" risk factor
not previously addressed or substandard treatment, suggesting that a more intense evaluation or
treatment of known risk factors is needed. For example, DM2 or LDL subclassification... pb*
Insulin sensitivity and atherosclerosis. The Insulin Resistance Atherosclerosis Study (IRAS)
Investigators. Circulation. 1996 May 15;93(10):1809-17. tinyurl.com25z4jOpen ↗ There was a
significant negative association between insulin sensitivity and the IMT of the carotid artery both
in Hispanics and in non-Hispanic whites. This effect was reduced but not totally explained by
adjustment for traditional cardiovascular disease risk factors, glucose tolerance, measures of
adiposity, and fasting insulin levels.
Association between carotid intima-media thickness and low-density lipoprotein size and
susceptibility of low-density lipoprotein to oxidation in asymptomatic members of familial combined
hyperlipidemia families. Stroke. 2002 May;33(5):1255-60. tinyurl.comyq9byOpen ↗ LDL particle size,
serum total cholesterol, and alpha-tocopherol in LDL were independently associated with lag time for
LDL oxidation in multivariate analysis. LDL particle size was associated with carotid mean IMT
independently of clinical, lipid, and antioxidant variables in multivariate analysis. Although the
susceptibility of LDL to oxidation in vitro was correlated with mean IMT, it did not have a
significant independent contribution to variation in mean IMT in the multivariate model.
*CIMT is a measure of atherosclerosis. Targeting CIMT directly by using medications known to regress
atherosclerosis over time requires a paradigm shift from yesterday's management of atherosclerosis.
By targeting the known pathways of atherosclerosis progression early, before clinical events occur
is now considered state of the art, and is considered "secondary prevention" against
atherosclerosis. -pb*
"Atherosclerosis is a progressive disease. While the short-term prognosis may be improved with
medical management and revascularization strategies, the underlying atherosclerotic disease process
must be addressed to improve long term patient outcome. Overwhelming scientific evidence
demonstrates that treatment alters the natural history of this disease, improves clinical outcomes,
and prolongs survival. The goal, whether it be during hospitalization or an outpatient visit for any
reason, in a patient with coronary artery disease, cerebral vascular disease, or peripheral vascular
disease is to ensure the initiation and maintenance of clinical trial evidence based therapies." -
quote from the UCLA atherosclerosis management site, CHAMP: med.ucla.educhampOpen ↗
Fonarow, G. C. and A. Gawlinski, Rational and Design of the Cardiac Hospitalization Atherosclerosis
Management Program at the University of California Los Angeles, Am. J. Cardiol., 85:10A-17A, 2000.
* "CIMT is a direct measure of early atherosclerosis" Gregg Fonarow, exerpt from a private email
July 2003 -pb*
Noninvasive atherosclerosis imaging for predicting cardiovascular events and assessing therapeutic
interventions. Curr Atheroscler Rep. 2004 Jan;6(1):20-6. tinyurl.comyq5zuOpen ↗ Noninvasive
assessment of atherosclerosis offers an opportunity to provide individual cardiovascular risk
management and an opportunity to monitor the efficacy of therapy targeted toward atherosclerosis.
The three imaging modalities that currently hold the most promise at the clinical and research
levels are ultrasound for carotid intima-media thickness, computed tomography for coronary artery
calcification, and magnetic resonance imaging for carotid and aortic plaque imaging.
*CIMT is not the only noninvasive assessment of atherosclerosis available, but it is the safest and
most precise method. I hope these few studies help answer your question; regression of CIMT over
time has been strongly linked to regression of atherosclerosis and hence improved outcomes. These
quoted studies are just a few of many many studies indicating a regression of CIMT translates to
better outcomes, and that CIMT opens a window to effective and highly specific individualization of
atherosclerosis management. -pb*
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Patrick Blanchard, M.D. Board Certified in Family Medicine
SonoScore Winning against heart attack and stroke sonoscore.comsonoscore.comOpen ↗
