Cerebral hemodynamics, autoregulation, and blood pressure management.

INTRODUCTION Chronic hypertension may be the single most important modifiable risk factor for ischemic stroke (19). Antihypertensive therapy has been proven to reduce the risk of stroke in prospective, randomized controlled studies (7). Hypertension is common in patients presenting with acute ischemic stroke (4), but its treatment is controversial (9). In contrast to chronic hypertension, there is little clinical trial data to guide decisions regarding anti-hypertensive therapy in acute ischemic stroke. Furthermore, there are potential conflicting mechanisms by which patient outcome could be worsened. Reduction of mean arterial pressure can reduce blood flow to already ischemic regions and result in further ischemic injury. On the other hand, hypertension can increase the risk of cerebral edema or hemorrhage, particularly in patients who have received thrombolytic therapy. In this lecture, we will review the data concerning these two conflicting mechanisms and discuss current guidelines for the treatment of hypertension in patients with acute ischemic stroke.