Causes of Ischemic Stroke

Ischemic stroke is a heterogeneous disease and occurs due to a multitude of underlying pathologic processes. The brain is such an exquisitely sensitive reporting system that small infarctions, well below the size that causes clinical signs in other organ systems, can cause major disability in the brain. About 85% of all strokes are due to ischemia, and in the majority of ischemic stroke, the mechanism responsible is understood (Fig. 2.1) [1]. An illustration of the causes of the majority of ischemic strokes is shown in Fig. 2.2, including atherosclerotic, cardiogenic, and lacunar (penetrating vessel) mechanisms. Large series have failed to identify a definite cause in 25–39% of patients with ischemic stroke, depending on the quality, completeness, and quickness of the clinical workup [1]. This group of strokes of unknown causes is known as cryptogenic stroke. This chapter reviews the pathways that lead to ischemic stroke. Causes of Ischemic Stroke