Carotid plaque microcalcification — a sign of instability?

Aim. To evaluate the potential of the MicroPure ultrasound technology for detecting microcalcification in carotid plaques in patients with acute coronary syndrome (ACS).

Material and methods. The study included 50 patients with cardiovascular diseases (65,62±11,12 years, 34 men), including 25 patients with ACS (64,0±11,5 years, 19 men) and 25 patients with chronic coronary artery disease (CAD) (67,2±10,7 years; 15 men). The patients underwent standard clinical and laboratory examination, as well as carotid ultrasound using a Canon Aplio a550 system (Japan) of 14,0 MHz. Scanning of the detected plaques was performed in B-mode and MicroPure mode for microcalcification analysis. Plaque microcalcification as such, the number (single or multiple) and location (cap, body, base, combined location) of microcalcifications in plaques were assessed.

Results. Plaque microcalcification was detected in all patients with ACS, whereas in the group of patients with CAD they were detected twice as rarely (100% vs 48%, p=0,0001). Microcalcifications were more often detected in the plaque cap and body in patients with ACS than in patients with CAD (43% vs 23%, p=0,0125 and 55,4% vs 14,6%, p<0,001, respectively). In both groups, both single and multiple microcalcifications were detected as follows: 26,3% and 73,7% in the ACS group and 28,12% and 71,8% in the CAD group, respectively (p>0,05).

Conclusion. Significant predominance of carotid plaque microcalcifications was detected in patients with ACS compared to patients with CAD. Detection of microcalcifications using novel ultrasound technologies may be an important sign of atherosclerotic plaque instability.

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