Management of Hypertension in Stroke

Introduction

Chronic hypertension is a known risk factor for acute ischemic as well as hemorrhagic strokes. There is an independent, graded relationship between the two, and hypertension is therefore aggressively treated in the outpatient environment in order to reduce future stroke risks . Ischemic strokes comprise the majority of all strokes. Although they can present in a myriad of manifestations, patients will usually have a focal onset of neurological symptoms at admission hinting toward this diagnosis. Cerebral autoregulation is integral to the delicate process of maintaining stable cerebral perfusion and brain tissue oxygenation against changes in the arterial blood pressure (BP). The classic description of cerebral autoregulation is that cerebral blood flow is maintained at a constant level across a wide range of mean arterial BP (60–150 mmHg) . Autoregulation occurs through changes in cerebral vascular resistance leading to vasodilation when peripheral BP is reduced and vasoconstriction when BP is elevated. In the face of longstanding hypertension, which leads to morphological changes in the vessel walls, this “autoregulatory window” is shifted toward higher BP such that reductions in cerebral blood flow can occur when BP is lowered within the 60–150 mmHg range .