Relationship between hemostatic markers and platelet indices in patients with aortic aneurysm.

The purpose of this study was to investigate whether platelet indices [ platelet count, mean platelet volume (MPV), platelet-large cell ratio (P-LCR) and platelet distribution width (PDW)] could serve as diagnostic tools to evaluate the potential significance of platelet heterogeneity on thrombus formation in patients with aortic aneurysm ( AA). Blood samples were obtained from 54 patients with AA ( mean age 73 years; 40 males and 14 females), and from 120 age-matched controls (AC; mean age 74 years; 61 males and 59 females). Blood platelet indices were measured using an automated counter for all AC (n = 120) and AA ( n = 54). Plasma thrombin-antithrombin III complex ( TAT), alpha(2)-plasmin inhibitor-plasmin complex (PIC), D-dimer, von Willebrand factor antigen (vWF: Ag) and interleukin-6 (IL-6) were also measured in part of AC and AA. In AA patients, TAT, PIC, D-dimer, vWF: Ag and IL-6 levels were significantly ( p <= 0.0005) higher than in AC. In the patients, TAT was significantly inversely correlated with platelet count (rho = - 0.302, p = 0.038, n = 48), and significantly positively correlated with MPV (rho = 0.329, p = 0.0373, n = 48), P- LCR (rho = 0.361, p = 0.0134, n = 48) and PDW (rho = 0.315, p = 0.0466, n = 48). PIC was negatively correlated with platelet count and inversely correlated with MPV, P- LCR and PDW. vWF: Ag was not correlated with platelet count, and inversely correlated with MPV, P- LCR and PDW in the patients. IL-6 was positively correlated with platelet count, and significantly inversely correlated with MPV, P- LCR and PDW in the patients. In AC, vWF: Ag was inversely correlated with platelet count and significantly positively correlated with MPV, P- LCR and PDW. However, PIC, TAT and IL-6 were not correlated with platelet indices in AC. D-dimer was not at all correlated with platelet indices both in AA and AC. In conclusion, the correlation between platelet indices and plasma hemostatic factor levels, e. g. TAT, PIC, D-dimer, vWF: Ag and IL-6, will be important factors for the understanding of platelet heterogeneity in patients with AA. Copyright (c) 2007 S. Karger AG, Basel.