A second macroscopic structure resembled a rope with few platelets made of woven strands of thinner yarns of VWF fibers. (A) Low-magnification SEM revealed that the crosscurrent mass adopted the structure of a rope made of strands of yarn (black arrows; diameter 10-15 μm) suspended above the glass slide. We surmise this rope formed in the streamwise direction at the edge of the chamber and was dislodged transversally after one side broke. (B) Higher magnification revealed a structure abundant in yarns of VWF, with few platelets compared to the occlusive transverse cable seen in Figure 4A. (C) SEM of representative example of the densest region of sheared (15 000/s; 10 minutes) collagen fibers in separate flow experiments without whole blood (n = 2). (D) Schematic of the structural hierarchy of the rope structure.