Coronary artery calcium score assessed by a 64 multislice computed tomography and early indexes of functional and structural vascular remodeling in cardiac syndrome X patients.

BACKGROUND

Regardless of normal coronary angiograms, coronary artery calcium (CAC) can be found in cardiac syndrome X (CSX) patients. According to some data, a relationship between the CAC score and markers of early atherosclerosis in CSX has been observed. Our aim was to assess whether the extent of the CAC score assessed by multislice computed tomography (MSCT) with a 64-slice system in CSX patients is related to brachial artery reactivity, intima-media thickness (IMT), and arterial compliance indexes.

METHODS AND RESULTS

High-resolution ultrasound was used to measure flow-mediated dilatation (FMD) and nitroglycerin-mediated vasodilatation, as well as the following parameters of arterial structural changes: IMT, pulse wave velocity, total arterial compliance, and stiffness index. MSCT was used to assess the presence and the quantity of CAC. The study group consisted of 46 CSX patients (mean age, 56.3 +/- 9 years), whereas the control group comprised 21 healthy subjects (mean age, 54.9 +/- 7 years). The assessment of the vascular parameters showed significantly decreased FMD and increased IMT in the CSX subjects (9.06% +/- 3.2% and 0.67 +/- 0.1 mm, respectively) in comparison to the control subjects (17.42% +/- 8.4% [P = .008] and 0.57 +/- 0.2 mm [P = .021], respectively). CAC was detectable in 19 CSX patients (41%) (CAC range according to Agatston score, 2-500; mean, 101.6; median, 26.5) and in 1 control subject (4.8%) (CAC value, 13). CSX patients with detectable CAC were characterized by a significantly higher age (P = .001), lower body mass index (P = .017), and increased stiffness index (P = .020); there were no differences in FMD and IMT values. In a multivariate logistic and linear regression analysis, age was the only risk factor independently associated with the presence of CAC (P = .001) and the log(CAC + 1) value (P = .01). In the subgroup of women, log(CAC + 1) significantly correlated with age (r = 0.587, P = .002) and stiffness index (r = 0.427, P = .024), and in a borderline significant manner, it correlated with weight (r = -0.329, P = .07) and waist-hip ratio (r = 0.315, P = .07). There were no significant correlations in the male subgroup.

CONCLUSIONS

Low ranges of CAC are frequently detectable in CSX patients, and the results are age-related and independent of impaired early indexes of functional and structural vascular remodeling.