Shear-dependent assembly of a transverse VWF–platelet cable in a stenosed microchannel. (A) Schematic illustrating left-to-right flow through a stenotic channel mimicking an artery, with associated high-shear thrombi. Channel walls are color-mapped by wall shear stress (blue, low; red, high), with peaks and steep gradients at the constriction slopes and throat. At the upstream edge, a large transverse occlusive mass spans the entire cross-section, composed of parallel platelet strings joined by VWF fiber “yarns.” (B) Schematic showing 2 platelet aggregates (orange), at the stenosis entrance, bridged by dense bundles of ULVWF fibers. These fibers form a high surface-area scaffold that tethers platelets and connects aggregates into a continuous transverse cable, resisting hydrodynamic drag and promoting luminal occlusion under high shear.