Carotid artery intima-media thickness, but not coronary artery calcium, predicts coronary vascular resistance in patients evaluated for coronary artery disease

• Published in: European heart journal cardiovascular imaging 2012-04, Vol.13 (4), p.317-323
• Main Authors: Danad, Ibrahim, Raijmakers, Pieter G, Kamali, Parisa, Harms, Hendrik J, de Haan, Stefan, Lubberink, Mark, van Kuijk, Cornelis, Hoekstra, Otto S, Lammertsma, Adriaan A, Smulders, Yvo M, Heymans, Martijn W, Tulevski, Igor I, van Rossum, Albert C, Knaapen, Paul
• Format: Article
• Language: English
• Subjects: Adult; Aged; Analysis of Variance; C-IMT; CAC score; Carotid Arteries - diagnostic imaging; Carotid Arteries - pathology; Carotid Artery Diseases - diagnostic imaging; Carotid Artery Diseases - pathology; Coronary Circulation; Coronary flow reserve; Coronary vascular resistance; Female; Health Status Indicators; Hemodynamics; Humans; Male; Middle Aged; O-15-water PET/CT; Positron-Emission Tomography; Predictive Value of Tests; Prognosis; Risk Assessment; Statistics as Topic; Tunica Intima - diagnostic imaging; Tunica Intima - pathology; Tunica Media - diagnostic imaging; Tunica Media - pathology; Ultrasonography; Vascular Calcification - diagnostic imaging; Vascular Calcification - pathology; Vascular Resistance
• ISSN: 2047-2404; 2047-2412
• DOI: 10.1093/ehjci/jes038

There is growing evidence that coronary artery disease (CAD) affects not only the conduit epicardial coronary arteries, but also the microvascular coronary bed. Moreover, coronary microvascular dysfunction (CMVD) often precedes the stage of clinically overt epicardial CAD. Coronary artery calcium (CAC) and carotid intima-media thickness (C-IMT) measured with computed tomography (CT) and ultrasound, respectively, are among the available techniques to non-invasively assess atherosclerotic burden. An increased CAC score and C-IMT have also been associated with CMVD. It is therefore of interest to explore and compare the potential of CAC against C-IMT to predict minimal coronary vascular resistance (CVR). We evaluated 120 patients (mean age 56 ± 9 years, 58 men) without a documented history of CAD in whom obstructive CAD was excluded. All patients underwent C-IMT measurements, CAC scoring, and vasodilator stress (15)O-water positron emission tomography (PET)/CT, during which the coronary flow reserve (CFR) and minimal CVR were analysed. Minimal CVR increased significantly with increasing tertiles of C-IMT (22 ± 6, 27 ± 11, and 28 ± 9 mmHg mL(-1)min(-1) g(-1), P < 0.01), whereas the CFR was comparable across all C-IMT groups (P = 0.50). Minimal CVR increased significantly with an increase in CAC score (23 ± 9, 27 ± 8, 32 ± 10, and 32 ± 7 mmHg mL(-1) min(-1) g(-1), P < 0.01), whereas the CFR did not show a significant decrease with higher CAC scores (P = 0.18). Multivariable regression analysis revealed that C-IMT (P = 0.03), but not CAC, was independently associated with minimal CVR. C-IMT, but not CAC score, independently predicts minimal CVR in patients with multiple cardiovascular risk factors and suspected of CAD.