RT Book, Section A1 Kerr, Jessica L. A2 Sutton, S. Scott SR Print(0) ID 1158313337 T1 Hypertension T2 McGraw-Hill's NAPLEX® Review Guide, 3e YR 2019 FD 2019 PB McGraw-Hill Education PP New York, NY SN 9781260135923 LK accesspharmacy.mhmedical.com/content.aspx?aid=1158313337 RD 2024/03/28 AB Hypertension is defined as persistently elevated arterial blood pressure (BP). BP is the mathematical product of peripheral vascular resistance (PVR) and cardiac output (CO) and hypertension is the result of increased PVR or CO. Aberrations in the normal function of neurohormonal systems, such as the renin-angiotensin-aldosterone system (RAAS), sympathetic nervous system (SNS), and disturbances in sodium, calcium, and natriuretic hormones, have been implicated in the pathophysiology of hypertension (Table 3-1). Hypertension is usually multifactorial; consequently, multiple antihypertensive drugs are often necessary to control BP. Cardiovascular risk reduction can occur with lower BP. A reduction in systolic blood pressure (SBP) as small as 2 mm Hg reduces the risk of death from ischemic heart disease or other vascular causes by 7% and from stroke by 10%. The majority of patients with hypertension have essential hypertension because their BP is elevated for unknown reasons. Secondary hypertension accounts for less than 10% of patients (Table 3-2).