Individual propensity for arterial thrombosis

Arterial thrombophilia independent of vascular pathology has not been previously defined either experimentally or epidemiologically. To address the existence of an individual propensity to arterial thrombosis, we exploited a previously developed procedure entailing traumatic (crush) injury of paired porcine carotid arteries for generating platelet-rich thrombi. Porcine carotid arteries were injured bilaterally by serial hemostat crushes. Thrombus generation was monitored by local accumulation of autologous ¹¹¹In-labeled platelets and Doppler blood flow. Within this cohort of animals of similar age and size, the lowest to the highest responders in thrombus mass spanned a 7-fold range, showing no correlation with shear, platelet or leukocyte count, or plasma concentrations of fibrinogen or von Willebrand factor. However, there was strong intra-individual correlation (r²=0.80; P<0.001) of thrombus deposition between carotid artery pairs. The wide variation in thrombotic response to a standardized stimulus, not accounted for by shear stress or typical hematological variables, appears to be an intrinsic propensity of the individual. The experimental system for thrombus generation is sufficiently quantitative for assessment of variables determining this propensity.