Venous thromboembolic disease encompasses two clinical conditions: Deep vein thrombosis (DVT) and pulmonary embolism (PE). Deep Vein Trombosis is the formation of a clot (thrombus) that occludes veins and prevents blood circulation. Vein thrombosis mainly affects the “deep veins” in the legs above or below the knee. This thrombus may be totally or partially dislodged and travel through the bloodstream. If the thrombus reaches the lungs, Pulmonary Embolism occurs. PE is a very serious and life-threatening complication.