6th July 2026

Complications

The commonest complications of a DVT include a PE and post-thrombotic syndrome. In post-thrombotic syndrome, a chronic condition, the thrombus obstructs blood flow, resulting in venous hypertension and valvular incompetence. This can lead to chronic venous insufficiency. As a result, patients may have leg pain, oedema, a feeling of “heaviness,” and skin hyperpigmentation. 

Figure 5 – Pathophysiology of post-thrombotic syndrome

Complications of a PE can be life threatening, and include recurrent thromboembolisms, right heart failure, and cardiogenic shock. When a thrombus occludes a pulmonary artery, it may cause a part of the lung to infarct. This is rare as the lung’s bronchial circulation is not disrupted and is generally adequate. However, if there is an infarct, the pressure in the pulmonary arterial bed may rise, causing cardiac output to drop. Eventually, the patient may go into shock.