Venous Pathophysiology

Understanding venous pathophysiology is the starting point to treat chronic venous disease (CVD) but most importantly to prevent its complication. CVD can be subdivided into congenital, primary, and secondary venous disease. Primary venous disease is the most prevalent form of the disease affecting two-thirds of patients with CVD. It is caused by an increased venous hydrostatic pressure transmitted to the vein wall, causing smooth muscle relaxation, endothelial damage, and extracellular matrix degradation with subsequent vein wall weakening and wall dilatation. Conversely, secondary venous disease is caused by a thrombotic event (i.e., deep vein thrombosis [DVT]) or is secondary to trauma. Regardless of the initial thrombi formation, the majority of the limbs with DVT evolve with thrombus resolution. Failure to resolve an obstruction by either partial or complete recanalization of the thrombosed segment is found in less than 10% of cases. Three anatomic and hemodynamic patterns are found following an episode of DVT: reflux, obstruction, or a combination of reflux and obstruction. The latter is the most aggressive pattern, which is related to significant risk of long-term postthrombotic complications such as limb edema and skin damage.