Noninvasive detection of increased carotid artery temperature in patients with coronary artery disease predicts major cardiovascular events at one year: Results from a prospective multicenter study


      • Microwave radiometry (MWR) allows noninvasive evaluation of carotid temperatures.
      • Carotid temperatures predict the incidence of MACE in patients with CAD.
      • Carotid temperatures offer incremental predictive value in current risk models.
      • MWR could become an initial screening test for evaluation of vascular inflammation.


      Background and aims

      Limited prospective data have been reported regarding the impact of carotid inflammation on cardiovascular events in patients with coronary artery disease (CAD). Microwave radiometry (MWR) is a noninvasive, simple method that has been used for evaluation of carotid artery temperature which, when increased, predicts ‘inflamed’ plaques with vulnerable characteristics. We prospectively tested the hypothesis that increased carotid artery temperature predicts future cerebro- and cardiovascular events in patients with CAD.


      Consecutive patients from 3 centers, with documented CAD by coronary angiography, were studied. In both carotid arteries, common carotid intima-media thickness and plaque thickness were evaluated by ultrasound. Temperature difference (ΔT), measured by MWR, was considered as the maximal temperature along the carotid artery minus the minimum; ΔT ≥0.90 °C was assigned as high. Major cardiovascular events (MACE, death, stroke, myocardial infarction or revascularization) were recorded during the following year.


      In total, 250 patients were studied; of them 40 patients (16%) had high ΔT values in both carotid arteries. MACEs occurred in 30% of patients having bilateral high ΔT versus 3.8% in the remaining patients (p<0.001). Bilateral high ΔT was independently associated with increased one-year MACE rate (HR = 6.32, 95% CI 2.42–16.53, p<0.001, by multivariate cox regression hazard model). The addition of ΔT information on a baseline model based on cardiovascular risk factors and extent of CAD significantly increased the prognostic value of the model (c-statistic increase 0.744 to 0.845, pdif = 0.05)


      Carotid inflammation, detected by MWR, has an incremental prognostic value in patients with documented CAD.


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        • Virmani R.
        • Burke A.P.
        • Farb A.
        • Kolodgie F.D.
        Pathology of the vulnerable plaque.
        J. Am. Coll. Cardiol. 2006; 47: C13-C18
        • Naghavi M.
        • Libby P.
        • Falk E.
        • et al.
        From vulnerable plaque to vulnerable patient: a call for new definitions and risk assessment strategies: part II.
        Circulation. 2003; 108: 1772-1778
        • Bots M.L.
        • Groenewegen K.A.
        • Anderson T.J.
        • et al.
        Common carotid intima-media thickness measurements do not improve cardiovascular risk prediction in individuals with elevated blood pressure: the USE-IMT collaboration.
        Hypertension. 2014; 63: 1173-1181
        • Lorenz M.W.
        • Polak J.F.
        • 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: 2053-2062
        • Steinvil A.
        • Sadeh B.
        • Bornstein N.M.
        • et al.
        Impact of carotid atherosclerosis on the risk of adverse cardiac events in patients with and without coronary disease.
        Stroke. 2014; 45: 2311-2317
        • Figueroa A.L.
        • Abdelbaky A.
        • Truong Q.A.
        • et al.
        Measurement of arterial activity on routine FDG PET/CT images improves prediction of risk of future CV events.
        JACC Cardiovasc Imaging. 2013; 6: 1250-1259
        • Figueroa A.L.
        • Takx R.A.
        • MacNabb M.H.
        • et al.
        Relationship between measures of adiposity, arterial inflammation, and subsequent cardiovascular events.
        Circ. Cardiovasc Imaging. 2016; 9: e004043
        • Moon S.H.
        • Cho Y.S.
        • Noh T.S.
        • Choi J.Y.
        • Kim B.T.
        • Lee K.H.
        Carotid FDG uptake improves prediction of future cardiovascular events in asymptomatic individuals.
        JACC Cardiovasc Imaging. 2015; 8: 949-956
        • Rominger A.
        • Saam T.
        • Wolpers S.
        • et al.
        18F-FDG PET/CT identifies patients at risk for future vascular events in an otherwise asymptomatic cohort with neoplastic disease.
        J. Nucl. Med. 2009; 50: 1611-1620
        • Casscells W.
        • Hathorn B.
        • David M.
        • et al.
        Thermal detection of cellular infiltrates in living atherosclerotic plaques: possible implications for plaque rupture and thrombosis.
        Lancet. 1996; 347: 1447-1451
        • Krams R.
        • Verheye S.
        • van Da mme L.C.
        • et al.
        In vivo temperature heterogeneity is associated with plaque regions of increased MMP-9 activity.
        Eur. Heart J. 2005; 26: 2200-2205
        • Verheye S.
        • De Meyer G.R.
        • Van Langenhove G.
        • Knaapen M.W.
        • Kockx M.M.
        In vivo temperature heterogeneity of atherosclerotic plaques is determined by plaque composition.
        Circulation. 2002; 105: 1596-1601
        • Zampeli E.
        • Raftakis I.
        • Michelongona A.
        • et al.
        Detection of subclinical synovial inflammation by microwave radiometry.
        PLoS One. 2013; 8 (e64606)
        • Toutouzas K.
        • Grassos H.
        • Synetos A.
        • et al.
        A new non-invasive method for detection of local infla mmation in atherosclerotic plaques: experimental application of microwave radiometry.
        Atherosclerosis. 2011; 215: 82-89
        • Toutouzas K.
        • Benetos G.
        • Drakopoulou M.
        • et al.
        Incremental predictive value of carotid inflammation in acute ischemic stroke.
        Stroke. 2015; 46: 272-274
        • Toutouzas K.
        • Benetos G.
        • Drakopoulou M.
        • et al.
        Morphological and functional assessment of carotid plaques have similar predictive accuracy for coronary artery disease.
        Stroke. 2013; 44: 2607-2609
        • Toutouzas K.
        • Drakopoulou M.
        • Aggeli C.
        • et al.
        In vivo measurement of plaque neovascularisation and thermal heterogeneity in intermediate lesions of human carotid arteries.
        Heart. 2012; 98: 1716-1721
        • Toutouzas K.
        • Grassos C.
        • Drakopoulou M.
        • et al.
        First in vivo application of microwave radiometry in human carotids: a new noninvasive method for detection of local inflammatory activation.
        J. Am. Coll. Cardiol. 2012; 59: 1645-1653
        • Touboul P.J.
        • Hennerici M.G.
        • Meairs S.
        • et al.
        Mannheim carotid intima-media thickness and plaque consensus (2004-2006-2011).
        Cerebrovasc. Dis. 2011; 2012 (An update on behalf of the advisory board of the 3rd, 4th and 5th watching the risk symposia, at the 13th, 15th and 20th European Stroke Conferences, Mannheim, Germany, 2004, Brussels, Belgium, 2006, and Hamburg, Germany): 290-296
        • Geroulakos G.
        • Ramaswami G.
        • Nicolaides A.
        • et al.
        Characterization of symptomatic and asymptomatic carotid plaques using high-resolution real-time ultrasonography.
        Br. J. Surg. 1993; 80: 1274-1277
        • Barrett A.
        • Myers P.
        Subcutaneous temperatures: a method of noninvasive sensing (New York, N.Y.).
        Science. 1975; 190: 669-671
        • Barrett A.
        • Myers P.
        Microwave thermography: a method of detecting subsurface thermal patterns.
        Bibl. Radiol. 1975; : 45-56
        • Toutouzas K.
        • Benetos G.
        • Drakopoulou M.
        • et al.
        Insights from a thermography-based method suggesting higher carotid inflammation in patients with diabetes mellitus and coronary artery disease.
        Diabetes Metab. 2014; 40: 431-438
        • Cheng J.M.
        • Garcia-Garcia H.M.
        • de Boer S.P.
        • et al.
        In vivo detection of high-risk coronary plaques by radiofrequency intravascular ultrasound and cardiovascular outcome: results of the ATHEROREMO-IVUS study.
        Eur. Heart J. 2014; 35: 639-647
        • Zielinski T.
        • Dzielinska Z.
        • Januszewicz A.
        • et al.
        Carotid intima-media thickness as a marker of cardiovascular risk in hypertensive patients with coronary artery disease.
        Am. J. Hypertens. 2007; 20: 1058-1064
        • Hirano M.
        • Nakamura T.
        • Kitta Y.
        • et al.
        Short-term progression of maximum intima-media thickness of carotid plaque is associated with future coronary events in patients with coronary artery disease.
        Atherosclerosis. 2011; 215: 507-512
        • Sirimarco G.
        • Amarenco P.
        • Labreuche J.
        • et al.
        Carotid atherosclerosis and risk of subsequent coronary event in outpatients with atherothrombosis.
        Stroke. 2013; 44: 373-379
        • Komorovsky R.
        • Desideri A.
        • Coscarelli S.
        • et al.
        Predictive value of associations between carotid and coronary artery disease in patients with acute coronary syndromes.
        Am. J. Cardiol. 2005; 95: 116-119
        • Honda O.
        • Sugiyama S.
        • Kugiyama K.
        • et al.
        Echolucent carotid plaques predict future coronary events in patients with coronary artery disease.
        J. Am. Coll. Cardiol. 2004; 43: 1177-1184
        • Hirano M.
        • Nakamura T.
        • Kitta Y.
        • et al.
        Assessment of carotid plaque echolucency in addition to plaque size increases the predictive value of carotid ultrasound for coronary events in patients with coronary artery disease and mild carotid atherosclerosis.
        Atherosclerosis. 2010; 211: 451-455
        • Calvert P.A.
        • Obaid D.R.
        • O'Sullivan M.
        • et al.
        Association between IVUS findings and adverse outcomes in patients with coronary artery disease: the VIVA (VH-IVUS in vulnerable atherosclerosis) study.
        JACC Cardiovasc Imaging. 2011; 4: 894-901
        • Vergallo R.
        • Ren X.
        • Yonetsu T.
        • et al.
        Pancoronary plaque vulnerability in patients with acute coronary syndrome and ruptured culprit plaque: a 3-vessel optical coherence tomography study.
        Am. Heart J. 2014; 167: 59-67
        • Myers K.S.
        • Rudd J.H.
        • Hailman E.P.
        • et al.
        Correlation between arterial FDG uptake and biomarkers in peripheral artery disease.
        JACC Cardiovasc Imaging. 2012; 5: 38-45
        • Toutouzas K.
        • Benetos G.
        • Karanasos A.
        • Chatzizisis Y.S.
        • Giannopoulos A.A.
        • Tousoulis D.
        Vulnerable plaque imaging: updates on new pathobiological mechanisms.
        Eur. Heart J. 2015; 36: 3147-3154