Platelet-derived chemokines, PF-4 and RANTES, are significantly increased in hemodynamically significant degenerative aortic stenosis
Abstrakt
The study focused on platelet-derived chemokines, platelet factor 4 (PF4,CXCL4) and RANTES (CCL5), in symptomatic degenerative aortic stenosis. Methods The study group was comprised of 124 consecutive patients (mean - SD age 71.6-9.5 years, 63.6% men) being considered for aortic valve replacement for symptomatic degenerative trileaflet valvular AoS, and were undergoing cardiac catheterization.
Blood samples were collected from the bulbus of the aorta at the beginning of catheterization. Laboratory values for serum levels of PF4 and RANTES were compared between: i) group A (N = 64) patients with AoS and without coronary artery disease (CAD), ii) group B (N = 60) patients with AoS and with stable CAD, and iii) group C (N = 42) control group; patients without AoS and without CAD.
Linear regression analyses were performed to adjust the compared groups for variables that might influence platelet activation. Degenerative AoS without CAD and also with CAD had significantly elevated serum concentrations of PF4 compared with control subjects (adjusted p = 0.0008 for comparison A vs.
C; p -0.00001 for comparison B vs. C).
Platelet-derived RANTES was increased in patients with AoS and without CAD compared to the control population (adjusted p = 0.0001). Levels of RANTES in patients with concurrent CAD were without significant difference (adjusted p = 0.130) from that in control group (probably due to deposition in atheroma).
The correlation between PF4 and RANTES was strong (rp = 0.647; p < 0.00001). No correlation was found between levels of chemokines and the mean pressure gradient across the aortic valve.
Platelet-derived chemokines, RANTES and PF4, are significantly increased in symptomatic degenerative AoS. Concentrations of circulating platelet-derived chemokines did not depend on the pressure gradient across the stenotic aortic valve.