Time-course changes in surface coverage by thrombi generated during perfusion of blood from normal controls, an AF patient, or a type 3 VWD patient.
A collagen-coated coverslip was fixed at several time points (1, 3, 5, and 7 minutes after initial platelet-surface interaction) during perfusion, and platelet thrombi labeled with mepacrine on a coverslip were evaluated by CLSM. The percentage of the area covered by thrombi (surface coverage) in a defined area (211 × 317 μm) within a frame was calculated at a height of 2 μm from the collagen surface. In control thrombi, each data point represents the average (± SD) of 15 areas examined (5 areas randomly selected in 3 independent perfusions of blood from 3 individual donors, respectively). In AF or VWD thrombi, each data point represents the average (± SD) of 10 areas examined (5 areas randomly selected in each of 2 separate perfusions). Under high shear rate (1500 s−1), the surface coverage of AF thrombi increased as a function of perfusion time to an extent comparable to that of controls, whereas almost no platelet-surface interactions were observed in the perfusion of VWD blood. In contrast, the surface coverage of AF or VWD thrombi was comparable to that of healthy controls throughout the observation periods under low shear rate conditions (300 s−1).
