How is vascular dysfunction in SSc?

Endothelial activation and damage (loss of normal vasomotor tone regulation by vasodilators decrease and vasoconstrictors increase, chemotraction and adhesion of inflammatory molecules, exposure of subendothelium to blood like platelets, fibrin and intravascular thrombus, activation of vascular muscle cell layer and migration to intima producing myofibroblasts and lead to fibrosis) So vessel loss occurs due to enhancement of vascular damage, proliferation of vascular intima, narrowing of vessel lumen, reduction of blood flow, digital ischemia and ulcers.