CYSTATIN C IS ASSOCIATED WITH THE EXTENT AND CHARACTERISTICS OF CORONARY ATHEROSCLEROSIS IN PATIENTS WITH PRESERVED RENAL FUNCTION

Objectives: Cystatin C, a sensitive and accurate marker of renal function has been associated with the severity of coronary atherosclerosis assessed by angiography and with future cardiovascular events in numerous studies. We aimed to evaluate the association between cystatin C levels and coronary plaque volume, composition and phenotype assessed by intravascular ultrasound (IVUS) and IVUS-derived virtual histology (IVUS-VH) in patients with preserved renal function.
Methods: 44 patients with angiographically documented coronary artery disease and complete intravascular imaging (IVUS and IVUS-VH) were included in the study. Patients were categorized into tertiles by cystatin C levels.
Results: Subjects in the high cystatin C tertile had significantly higher mean plaque burden (48.0% ± 6.9 vs. 42.8% ± 7.4, p=0.029), lower mean lumen area (8.1 mm2 ± 1.7 vs. 9.9 mm2 ± 3.1, p= 0.044) and a higher number of 5 mm vessel segments with minimum lumen area < 4 mm2 (17.9 ± 18.9 vs. 6.8 ± 11.7, p=0.021) compared to patients in the lower tertiles. In addition, CysC levels demonstrated significant positive correlation with mean plaque burden (r=0.35, p=0.021) and maximal plaque burden (r=0.3, p=0.047). Neither relative, nor absolute plaque components differed significantly according to CysC tertiles. The Liverpool active plaque score was significantly higher in the high tertile patients (LAPS 0.91 ± 1.0 vs. 0.18 ± 0.92, p=0.02).
Conclusion: Our study demonstrated a significant association of increased CysC levels with more advanced coronary artery disease characterized by more bulky plaques, lower mean lumen area and higher risk plaque phenotype in patients with preserved renal function.