Official reprint from UpToDate®
www.uptodate.com ©2017 UpToDate, Inc. and/or its affiliates. All Rights Reserved.

Carotid intima-media thickness

Eric de Groot, MD, PhD
John JP Kastelein, MD, PhD, FESC
Raphael Duivenvoorden, MD, PhD
Section Editor
Christopher P Cannon, MD
Deputy Editor
Brian C Downey, MD, FACC


Over the past decades, significant progress has been made to develop noninvasive atherosclerosis imaging techniques that can serve as surrogate end points for cardiovascular health status and prevention of disease. One of the rationales for atherosclerosis imaging originates from autopsy studies in adolescents and young adults, which revealed that atherosclerosis is present early in life and precedes the occurrence of cardiovascular events. Consequently, using imaging to detect early atherosclerosis has the potential to define the status and predict the risk of future cardiovascular events, as well as evaluate cardiovascular drug efficacy. One of the most widely used and best validated atherosclerosis imaging techniques is the ultrasound carotid intima-media thickness (CIMT) measurement.

The techniques for imaging and measuring CIMT along with the potential clinical applications of CIMT will be discussed. Carotid artery imaging for the detection of significant obstruction carotid disease is discussed separately. (See "Evaluation of carotid artery stenosis".)


CIMT can be measured using either high resolution ultrasound or magnetic resonance imaging (MRI). At present, carotid ultrasound has provided the majority of imaging data and, with its increasing availability, MRI has emerged as the technology with novel applications.

Image acquisition — The large superficial arteries, in particular the carotid arteries (figure 1), can be visualized at high resolution with B-mode (or "brightness" mode) ultrasound using linear array transducers for superficial and vascular structures (typically broadband transducers with frequency ranges 5 to 15 MHz and a high signal to noise ratio are used). The spatial resolution obtained with these transducers is on the order of 0.05 mm axially and 0.2 mm laterally. In most scan protocols, carotid ultrasound images are obtained from the near and far walls of the right and left distal common carotid arteries, the carotid bifurcation (image 1), and the proximal internal carotid arterial segments. CIMT in an individual patient is therefore often a composite of intima-media thickness measurements of various arterial segments, sometimes under multiple angles of insonation. (See "Basic principles and safety of diagnostic ultrasound in obstetrics and gynecology", section on 'Resolution'.)

Measurement technique — For CIMT measurements, longitudinal images of the carotid arteries are obtained in which the leading edges of the lumen-intima and media-adventitia interfaces (the "double-line pattern") of the arterial wall represent intima-media complex (image 1) [1,2]. Typically, normal common carotid CIMT at age 10 is approximately 0.4 to 0.5 mm, while from the fifth decade of life onward this progresses to 0.7 to 0.8 mm or more [3].

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information on subscription options, click below on the option that best describes you:

Subscribers log in here

Literature review current through: Oct 2017. | This topic last updated: Nov 13, 2017.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.
  1. de Groot E, van Leuven SI, Duivenvoorden R, et al. Measurement of carotid intima-media thickness to assess progression and regression of atherosclerosis. Nat Clin Pract Cardiovasc Med 2008; 5:280.
  2. Naqvi TZ, Lee MS. Carotid intima-media thickness and plaque in cardiovascular risk assessment. JACC Cardiovasc Imaging 2014; 7:1025.
  3. Iana Simova. Intima-media thickness: Appropriate evaluation and proper meausrement, described. E-Journal of the ESC Council for Cardiology Practice 2015; 13:1.
  4. Meuwese MC, de Groot E, Duivenvoorden R, et al. ACAT inhibition and progression of carotid atherosclerosis in patients with familial hypercholesterolemia: the CAPTIVATE randomized trial. JAMA 2009; 301:1131.
  5. Pasternak RC, Abrams J, Greenland P, et al. 34th Bethesda Conference: Task force #1--Identification of coronary heart disease risk: is there a detection gap? J Am Coll Cardiol 2003; 41:1863.
  6. Akosah KO, Schaper A, Cogbill C, Schoenfeld P. Preventing myocardial infarction in the young adult in the first place: how do the National Cholesterol Education Panel III guidelines perform? J Am Coll Cardiol 2003; 41:1475.
  7. Øygarden H. Carotid Intima-Media Thickness and Prediction of Cardiovascular Disease. J Am Heart Assoc 2017; 6.
  8. Berry JD, Liu K, Folsom AR, et al. Prevalence and progression of subclinical atherosclerosis in younger adults with low short-term but high lifetime estimated risk for cardiovascular disease: the coronary artery risk development in young adults study and multi-ethnic study of atherosclerosis. Circulation 2009; 119:382.
  9. Redberg RF, Vogel RA, Criqui MH, et al. 34th Bethesda Conference: Task force #3--What is the spectrum of current and emerging techniques for the noninvasive measurement of atherosclerosis? J Am Coll Cardiol 2003; 41:1886.
  10. Den Ruijter HM, Peters SA, Anderson TJ, et al. Common carotid intima-media thickness measurements in cardiovascular risk prediction: a meta-analysis. JAMA 2012; 308:796.
  11. Lorenz MW, Polak JF, Kavousi M, et al. Carotid intima-media thickness progression to predict cardiovascular events in the general population (the PROG-IMT collaborative project): a meta-analysis of individual participant data. Lancet 2012; 379:2053.
  12. Nambi V, Chambless L, Folsom AR, et al. Carotid intima-media thickness and presence or absence of plaque improves prediction of coronary heart disease risk: the ARIC (Atherosclerosis Risk In Communities) study. J Am Coll Cardiol 2010; 55:1600.
  13. Polak JF, Pencina MJ, Pencina KM, et al. Carotid-wall intima-media thickness and cardiovascular events. N Engl J Med 2011; 365:213.
  14. Baldassarre D, Hamsten A, Veglia F, et al. Measurements of carotid intima-media thickness and of interadventitia common carotid diameter improve prediction of cardiovascular events: results of the IMPROVE (Carotid Intima Media Thickness [IMT] and IMT-Progression as Predictors of Vascular Events in a High Risk European Population) study. J Am Coll Cardiol 2012; 60:1489.
  15. Tzoulaki I, Liberopoulos G, Ioannidis JP. Assessment of claims of improved prediction beyond the Framingham risk score. JAMA 2009; 302:2345.
  16. Mark DB, Shaw LJ, Lauer MS, et al. 34th Bethesda Conference: Task force #5--Is atherosclerosis imaging cost effective? J Am Coll Cardiol 2003; 41:1906.
  17. Lorenz MW, Schaefer C, Steinmetz H, Sitzer M. Is carotid intima media thickness useful for individual prediction of cardiovascular risk? Ten-year results from the Carotid Atherosclerosis Progression Study (CAPS). Eur Heart J 2010; 31:2041.
  18. Goff DC Jr, Lloyd-Jones DM, Bennett G, et al. 2013 ACC/AHA guideline on the assessment of cardiovascular risk: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2014; 63:2935.
  19. Crouse JR 3rd, Byington RP, Bond MG, et al. Pravastatin, Lipids, and Atherosclerosis in the Carotid Arteries (PLAC-II). Am J Cardiol 1995; 75:455.
  20. Hodis HN, Mack WJ, LaBree L, et al. Reduction in carotid arterial wall thickness using lovastatin and dietary therapy: a randomized controlled clinical trial. Ann Intern Med 1996; 124:548.
  21. MacMahon S, Sharpe N, Gamble G, et al. Effects of lowering average of below-average cholesterol levels on the progression of carotid atherosclerosis: results of the LIPID Atherosclerosis Substudy. LIPID Trial Research Group. Circulation 1998; 97:1784.
  22. de Groot E, Jukema JW, Montauban van Swijndregt AD, et al. B-mode ultrasound assessment of pravastatin treatment effect on carotid and femoral artery walls and its correlations with coronary arteriographic findings: a report of the Regression Growth Evaluation Statin Study (REGRESS). J Am Coll Cardiol 1998; 31:1561.
  23. Smilde TJ, van Wissen S, Wollersheim H, et al. Effect of aggressive versus conventional lipid lowering on atherosclerosis progression in familial hypercholesterolaemia (ASAP): a prospective, randomised, double-blind trial. Lancet 2001; 357:577.
  24. Taylor AJ, Kent SM, Flaherty PJ, et al. ARBITER: Arterial Biology for the Investigation of the Treatment Effects of Reducing Cholesterol: a randomized trial comparing the effects of atorvastatin and pravastatin on carotid intima medial thickness. Circulation 2002; 106:2055.
  25. Furberg CD, Adams HP Jr, Applegate WB, et al. Effect of lovastatin on early carotid atherosclerosis and cardiovascular events. Asymptomatic Carotid Artery Progression Study (ACAPS) Research Group. Circulation 1994; 90:1679.
  26. Mercuri M, Bond MG, Sirtori CR, et al. Pravastatin reduces carotid intima-media thickness progression in an asymptomatic hypercholesterolemic mediterranean population: the Carotid Atherosclerosis Italian Ultrasound Study. Am J Med 1996; 101:627.
  27. Salonen R, Nyyssönen K, Porkkala E, et al. Kuopio Atherosclerosis Prevention Study (KAPS). A population-based primary preventive trial of the effect of LDL lowering on atherosclerotic progression in carotid and femoral arteries. Circulation 1995; 92:1758.
  28. Crouse JR 3rd, Raichlen JS, Riley WA, et al. Effect of rosuvastatin on progression of carotid intima-media thickness in low-risk individuals with subclinical atherosclerosis: the METEOR Trial. JAMA 2007; 297:1344.
  29. Braamskamp MJAM, Langslet G, McCrindle BW, et al. Effect of Rosuvastatin on Carotid Intima-Media Thickness in Children With Heterozygous Familial Hypercholesterolemia: The CHARON Study (Hypercholesterolemia in Children and Adolescents Taking Rosuvastatin Open Label). Circulation 2017; 136:359.
  30. Wiegman A, de Groot E, Hutten BA, et al. Arterial intima-media thickness in children heterozygous for familial hypercholesterolaemia. Lancet 2004; 363:369.
  31. Taylor AJ, Sullenberger LE, Lee HJ, et al. Arterial Biology for the Investigation of the Treatment Effects of Reducing Cholesterol (ARBITER) 2: a double-blind, placebo-controlled study of extended-release niacin on atherosclerosis progression in secondary prevention patients treated with statins. Circulation 2004; 110:3512.
  32. Taylor AJ, Lee HJ, Sullenberger LE. The effect of 24 months of combination statin and extended-release niacin on carotid intima-media thickness: ARBITER 3. Curr Med Res Opin 2006; 22:2243.
  33. Blankenhorn DH, Selzer RH, Crawford DW, et al. Beneficial effects of colestipol-niacin therapy on the common carotid artery. Two- and four-year reduction of intima-media thickness measured by ultrasound. Circulation 1993; 88:20.
  34. Mack WJ, Selzer RH, Hodis HN, et al. One-year reduction and longitudinal analysis of carotid intima-media thickness associated with colestipol/niacin therapy. Stroke 1993; 24:1779.
  35. Kastelein JJ, van Leuven SI, Burgess L, et al. Effect of torcetrapib on carotid atherosclerosis in familial hypercholesterolemia. N Engl J Med 2007; 356:1620.
  36. Bots ML, Visseren FL, Evans GW, et al. Torcetrapib and carotid intima-media thickness in mixed dyslipidaemia (RADIANCE 2 study): a randomised, double-blind trial. Lancet 2007; 370:153.
  37. Kastelein JJ, Akdim F, Stroes ES, et al. Simvastatin with or without ezetimibe in familial hypercholesterolemia. N Engl J Med 2008; 358:1431.
  38. Hedblad B, Wikstrand J, Janzon L, et al. Low-dose metoprolol CR/XL and fluvastatin slow progression of carotid intima-media thickness: Main results from the Beta-Blocker Cholesterol-Lowering Asymptomatic Plaque Study (BCAPS). Circulation 2001; 103:1721.
  39. Wiklund O, Hulthe J, Wikstrand J, et al. Effect of controlled release/extended release metoprolol on carotid intima-media thickness in patients with hypercholesterolemia: a 3-year randomized study. Stroke 2002; 33:572.
  40. Pitt B, Byington RP, Furberg CD, et al. Effect of amlodipine on the progression of atherosclerosis and the occurrence of clinical events. PREVENT Investigators. Circulation 2000; 102:1503.
  41. Lonn E, Yusuf S, Dzavik V, et al. Effects of ramipril and vitamin E on atherosclerosis: the study to evaluate carotid ultrasound changes in patients treated with ramipril and vitamin E (SECURE). Circulation 2001; 103:919.
  42. MacMahon S, Sharpe N, Gamble G, et al. Randomized, placebo-controlled trial of the angiotensin-converting enzyme inhibitor, ramipril, in patients with coronary or other occlusive arterial disease. PART-2 Collaborative Research Group. Prevention of Atherosclerosis with Ramipril. J Am Coll Cardiol 2000; 36:438.
  43. Zanchetti A, Crepaldi G, Bond MG, et al. Different effects of antihypertensive regimens based on fosinopril or hydrochlorothiazide with or without lipid lowering by pravastatin on progression of asymptomatic carotid atherosclerosis: principal results of PHYLLIS--a randomized double-blind trial. Stroke 2004; 35:2807.
  44. Zanchetti A, Bond MG, Hennig M, et al. Calcium antagonist lacidipine slows down progression of asymptomatic carotid atherosclerosis: principal results of the European Lacidipine Study on Atherosclerosis (ELSA), a randomized, double-blind, long-term trial. Circulation 2002; 106:2422.
  45. Simon A, Gariépy J, Moyse D, Levenson J. Differential effects of nifedipine and co-amilozide on the progression of early carotid wall changes. Circulation 2001; 103:2949.
  46. Borhani NO, Mercuri M, Borhani PA, et al. Final outcome results of the Multicenter Isradipine Diuretic Atherosclerosis Study (MIDAS). A randomized controlled trial. JAMA 1996; 276:785.
  47. Stanton AV, Chapman JN, Mayet J, et al. Effects of blood pressure lowering with amlodipine or lisinopril on vascular structure of the common carotid artery. Clin Sci (Lond) 2001; 101:455.
  48. Hoogerbrugge N, de Groot E, de Heide LH, et al. Doxazosin and hydrochlorothiazide equally affect arterial wall thickness in hypertensive males with hypercholesterolaemia (the DAPHNE study). Doxazosin Atherosclerosis Progression Study in Hypertensives in the Netherlands. Neth J Med 2002; 60:354.
  49. Ludwig M, Stapff M, Ribeiro A, et al. Comparison of the effects of losartan and atenolol on common carotid artery intima-media thickness in patients with hypertension: results of a 2-year, double-blind, randomized, controlled study. Clin Ther 2002; 24:1175.
  50. Hodis HN, Mack WJ, LaBree L, et al. Alpha-tocopherol supplementation in healthy individuals reduces low-density lipoprotein oxidation but not atherosclerosis: the Vitamin E Atherosclerosis Prevention Study (VEAPS). Circulation 2002; 106:1453.
  51. Magliano D, McNeil J, Branley P, et al. The Melbourne Atherosclerosis Vitamin E Trial (MAVET): a study of high dose vitamin E in smokers. Eur J Cardiovasc Prev Rehabil 2006; 13:341.
  52. Durga J, Bots ML, Schouten EG, et al. Effect of 3 y of folic acid supplementation on the progression of carotid intima-media thickness and carotid arterial stiffness in older adults. Am J Clin Nutr 2011; 93:941.
  53. Hodis HN, Mack WJ, Dustin L, et al. High-dose B vitamin supplementation and progression of subclinical atherosclerosis: a randomized controlled trial. Stroke 2009; 40:730.
  54. Zoungas S, McGrath BP, Branley P, et al. Cardiovascular morbidity and mortality in the Atherosclerosis and Folic Acid Supplementation Trial (ASFAST) in chronic renal failure: a multicenter, randomized, controlled trial. J Am Coll Cardiol 2006; 47:1108.
  55. Hodis HN, Mack WJ, Lobo RA, et al. Estrogen in the prevention of atherosclerosis. A randomized, double-blind, placebo-controlled trial. Ann Intern Med 2001; 135:939.
  56. Bots ML, Evans GW, Riley W, et al. The effect of tibolone and continuous combined conjugated equine oestrogens plus medroxyprogesterone acetate on progression of carotid intima-media thickness: the Osteoporosis Prevention and Arterial effects of tiboLone (OPAL) study. Eur Heart J 2006; 27:746.
  57. Colacurci N, Fornaro F, Cobellis L, et al. Raloxifene slows down the progression of intima-media thickness in postmenopausal women. Menopause 2007; 14:879.
  58. Byington RP, Furberg CD, Herrington DM, et al. Effect of estrogen plus progestin on progression of carotid atherosclerosis in postmenopausal women with heart disease: HERS B-mode substudy. Arterioscler Thromb Vasc Biol 2002; 22:1692.
  59. Mazzone T, Meyer PM, Feinstein SB, et al. Effect of pioglitazone compared with glimepiride on carotid intima-media thickness in type 2 diabetes: a randomized trial. JAMA 2006; 296:2572.
  60. Langenfeld MR, Forst T, Hohberg C, et al. Pioglitazone decreases carotid intima-media thickness independently of glycemic control in patients with type 2 diabetes mellitus: results from a controlled randomized study. Circulation 2005; 111:2525.
  61. Hedblad B, Zambanini A, Nilsson P, et al. Rosiglitazone and carotid IMT progression rate in a mixed cohort of patients with type 2 diabetes and the insulin resistance syndrome: main results from the Rosiglitazone Atherosclerosis Study. J Intern Med 2007; 261:293.
  62. O'Leary DH, Reuwer AQ, Nissen SE, et al. Effect of rimonabant on carotid intima-media thickness (CIMT) progression in patients with abdominal obesity and metabolic syndrome: the AUDITOR Trial. Heart 2011; 97:1143.
  63. Peters SA, den Ruijter HM, Grobbee DE, Bots ML. Results from a carotid intima-media thickness trial as a decision tool for launching a large-scale morbidity and mortality trial. Circ Cardiovasc Imaging 2013; 6:20.
  64. Yuan C, Beach KW, Smith LH Jr, Hatsukami TS. Measurement of atherosclerotic carotid plaque size in vivo using high resolution magnetic resonance imaging. Circulation 1998; 98:2666.
  65. Duivenvoorden R, de Groot E, Elsen BM, et al. In vivo quantification of carotid artery wall dimensions: 3.0-Tesla MRI versus B-mode ultrasound imaging. Circ Cardiovasc Imaging 2009; 2:235.
  66. Duivenvoorden R, de Groot E, Afzali H, et al. Comparison of in vivo carotid 3.0-T magnetic resonance to B-mode ultrasound imaging and histology in a porcine model. JACC Cardiovasc Imaging 2009; 2:744.
  67. Li F, Yarnykh VL, Hatsukami TS, et al. Scan-rescan reproducibility of carotid atherosclerotic plaque morphology and tissue composition measurements using multicontrast MRI at 3T. J Magn Reson Imaging 2010; 31:168.
  68. Underhill HR, Yuan C, Yarnykh VL, et al. Predictors of surface disruption with MR imaging in asymptomatic carotid artery stenosis. AJNR Am J Neuroradiol 2010; 31:487.
  69. Takaya N, Yuan C, Chu B, et al. Association between carotid plaque characteristics and subsequent ischemic cerebrovascular events: a prospective assessment with MRI--initial results. Stroke 2006; 37:818.
  70. Altaf N, Daniels L, Morgan PS, et al. Detection of intraplaque hemorrhage by magnetic resonance imaging in symptomatic patients with mild to moderate carotid stenosis predicts recurrent neurological events. J Vasc Surg 2008; 47:337.
  71. Parmar JP, Rogers WJ, Mugler JP 3rd, et al. Magnetic resonance imaging of carotid atherosclerotic plaque in clinically suspected acute transient ischemic attack and acute ischemic stroke. Circulation 2010; 122:2031.
  72. Wagenknecht L, Wasserman B, Chambless L, et al. Correlates of carotid plaque presence and composition as measured by MRI: the Atherosclerosis Risk in Communities Study. Circ Cardiovasc Imaging 2009; 2:314.
  73. Wasserman BA, Sharrett AR, Lai S, et al. Risk factor associations with the presence of a lipid core in carotid plaque of asymptomatic individuals using high-resolution MRI: the multi-ethnic study of atherosclerosis (MESA). Stroke 2008; 39:329.
  74. Duivenvoorden R, Holleboom AG, van den Bogaard B, et al. Carriers of lecithin cholesterol acyltransferase gene mutations have accelerated atherogenesis as assessed by carotid 3.0-T magnetic resonance imaging [corrected]. J Am Coll Cardiol 2011; 58:2481.
  75. Bochem AE, van Wijk DF, Holleboom AG, et al. ABCA1 mutation carriers with low high-density lipoprotein cholesterol are characterized by a larger atherosclerotic burden. Eur Heart J 2013; 34:286.
  76. Fayad ZA, Mani V, Woodward M, et al. Safety and efficacy of dalcetrapib on atherosclerotic disease using novel non-invasive multimodality imaging (dal-PLAQUE): a randomised clinical trial. Lancet 2011; 378:1547.
  77. Lee JM, Robson MD, Yu LM, et al. Effects of high-dose modified-release nicotinic acid on atherosclerosis and vascular function: a randomized, placebo-controlled, magnetic resonance imaging study. J Am Coll Cardiol 2009; 54:1787.
  78. Underhill HR, Yuan C, Zhao XQ, et al. Effect of rosuvastatin therapy on carotid plaque morphology and composition in moderately hypercholesterolemic patients: a high-resolution magnetic resonance imaging trial. Am Heart J 2008; 155:584.e1.