Abstract Details

Title Lower Coated-Platelet Levels, RANTES and Fibrinogen Correlate with the Number of Cerebral Microbleeds in Carotid Stenosis

Topic Cerebrovascular Disease and Interventional Neurology

Presentation(s) P1 - Poster Session 1 (12:00 PM-1:00 PM)

Poster/Presentation
Number 4-010

Objective To explore if platelet procoagulant potential and inflammatory markers correlate with the number of microbleeds in asymptomatic carotid stenosis patients.

Background Mechanisms leading to the development of cerebral microbleeds are incompletely understood. Coated-platelets are a subset of procoagulant platelets observed upon dual agonist stimulation with collagen and thrombin. Previously, we have shown that higher coated-platelet levels are associated with increased risk for recurrent or incident stroke in patients with carotid stenosis. In contrast, lower levels were observed in ischemic stroke patients with microbleeds and in those with early hemorrhagic complications. We now explore the association between coated-platelets, soluble mediators of inflammation, cell adhesion, angiogenesis and coagulation and the number of microbleeds.

Design/Methods Asymptomatic patients with ≥50% carotid stenosis were enrolled, coated-platelets assayed, and plasma obtained for measurement of 58 plasma biomarkers. The number of microbleeds (defined as round 5-10 mm lesions, appearing black and with a blooming effect on susceptibility-weighted sequences) on MRI studies within 12 months of enrollment was recorded by two independent blinded raters. Correlations between coated-platelet levels, levels of plasma biomarkers and number of microbleeds were calculated using Pearson’s correlation coefficient.

Results

Thirty-two subjects with a mean age of 71.3 years (range 45-81) were analyzed. Inter-rater agreement for the number of microbleeds was excellent (97%). Among all variables evaluated, only coated-platelet levels (r=- 0.4216, p=0.018), fibrinogen (r=-0.4239, p=0.015) and RANTES (r=-0.3564, p=0.045) correlated with the number of microbleeds.

Conclusions

Our results demonstrate that lower levels of coated-platelets are associated with an increased number of microbleeds. We have also identified two inflammatory markers (fibrinogen and RANTES) inversely correlating with the number of microbleeds. These data support a role for both platelet procoagulant potential and inflammatory pathways in mechanisms leading to the development of cerebral microbleeds.

Authors/Disclosures
Sergio A. Ramirez-Salazar, MD (Dartmouth Hitchcock Medical Center) PRESENTER	Dr. Ramirez-Salazar has nothing to disclose.
Angelia Kirkpatrick	Angelia Kirkpatrick has nothing to disclose.
Andrea Vincent	Andrea Vincent has received personal compensation for serving as an employee of Vista LifeSciences. The institution of Andrea Vincent has received research support from Medical Technology Enterprise Consortium (MTEC).
Bappaditya Ray, MD (UT Southwestern Medical Center)	Dr. Ray has nothing to disclose.
	No disclosure on file
	No disclosure on file
Andriy Yabluchanskiy	Andriy Yabluchanskiy has nothing to disclose.
George Dale	George Dale has nothing to disclose.
Calin I. Prodan, MD (Univ of Oklahoma - Neurology Dept)	The institution of Dr. Prodan has received research support from US Department of Veterans Affairs (Merit award CX000340).