[Mechanisms and causes of cerebral ischemic accidents]

The treatment of an ischaemic stroke requires the understanding of its mechanism and the diagnosis of its cause. Two main pathophysiologic mechanisms are implicated: thromboembolic occlusion and hemodynamic failure. The knowledge of the pathophysiology is crucial to the therapeutic options particularly as regards anti-thrombotic treatments and strict bed rest. As regards etiology, most ischaemic strokes are due to 3 conditions: large artery atheroma, cardiac diseases and small perforating arteries diseases. There are numerous other causes (arterial, toxic, metabolic...) which are rare but must be looked for particularly in young subjects devoid of cardiac diseases. The discovery of a cause is important for the acute treatment of an ischaemic stroke and for the choice of secondary prevention measures.