ABSTRACT
INTRODUCTION A blood clot that forms in response to injury, e.g., a cut, is a normal physiological process by which the body controls hemorrhage. Thrombosis is the formation of a blood clot in a pathological location, e.g., in response to the rupture of an atherosclerotic plaque in a cerebral artery. Thrombus formation can result in occlusion of blood fl ow with major clinical consequences, as discussed in detail elsewhere in this book. The purpose of this chapter is to discuss the basic science of thrombus formation. For simplicity, this chapter will be divided into two parts: ( 1 ) platelets and ( 2 ) the coagulation cascade. However, as discussed below, these two components of thrombus formation are an overlapping, intertwined continuum.
