The related blood clot problems—deep vein thrombosis (DVT) and pulmonary embolism (PE)—are known as ‘venous thromboembolism’ (VTE for short) [1] and VTE is a common cause of death in Australia [2].

DVT refers to a blood clot that forms in one of the major deep veins of the lower legs or thighs, or sometimes in the pelvis [3]. A clot blocks blood circulation through these veins, which carry blood from the lower body back to the heart. The blockage can be painful and cause swelling and redness in the affected leg [3]. Blood clots can also form in veins close to the surface of the skin and cause thrombophlebitis [3].

A complication of DVT that can result in serious illness occurs when a clot breaks loose, or ‘embolises’, and travels through the bloodstream, causing blockage of blood vessels (pulmonary arteries) in the lung, known as PE [1,3,4]. If this happens, it may cause difficulty in breathing, chest pain, and blood-stained phlegm [1,3,4].

The figure shows how a DVT embolises from the left leg and travels through the bloodstream and blocks a pulmonary artery in the left lung.

VTEMatters offers general information only. Please see a healthcare professional for medical advice.


1. National Blood Clot Alliance. At-a-glance: blood clots. Accessed on 22 November 2018.
2. The Australia and New Zealand Working Party on the Management and Prevention of Venous Thromboembolism. Prevention of venous thromboembolism (5th Edition). 2010.
3. Cleveland Clinic. Deep Vein Thrombosis (DVT). Accessed on 22 November 2018.
4. Cleveland Clinic. Pulmonary embolism. Accessed on 22 November 2018.