The cerebral circulation and cerebrovascular disease II: Pathogenesis of cerebrovascular disease

Abstract

In this paper, we review the cerebral circulation and cerebrovascular disease (CVD) with an overview of the major types of CVD pathogenesis. These, as categorized here, are as follows: occlusive injury intrinsic to blood vessels, occlusive injury extrinsic to blood vessels, cerebral hypoperfusion, and cerebral hemorrhage. Following an overview of each of these categories, we conclude with a discussion of cerebral edema to illustrate how the pathological origins we covered can progress clinically. The content of this paper sets the stage for the detailed, clinically oriented discussion of stroke with which our series culminates in its subsequent Part III.

Keywords: Atherosclerosis; cerebal hemorrhage; cerebral circulation; cerebral edema; cerebral emboli; cerebral hypoperfusion; cerebral vessel damage; cerebrovascular disease.

Figure 1

The main features of atherosclerotic pathogenesis. Under nonpathogenic circumstances, an intact arterial endothelium (represented here as dots in light blue) prevents the ingress of atherosclerotic mediators. When normal endothelial function is compromised by factors such as hemodynamic stress and hyperlipidemia, however, the entry of low-density lipoprotein is facilitated. This begins the pathogenic cascade that culminates in the formation of an atherosclerotic lesion. Once formed, these lesions may continue to expand, resulting in cerebrovascular disease by occlusion. Alternatively, if possessed of certain predisposing histological features,[25] they may produce cerebrovascular disease through thrombosis or hemorrhage